├── .flake8 ├── .github └── workflows │ └── ci.yml ├── .gitignore ├── .readthedocs.yml ├── CHANGELOG.md ├── COPYING ├── MANIFEST.in ├── Makefile ├── README.rst ├── VERSION ├── docs ├── _static │ └── .gitignore ├── caches.rst ├── common_patterns.rst ├── compression_and_serialisation.rst ├── conf.py ├── index.rst ├── keys.rst └── rationale.rst ├── make.bat ├── mypy.ini ├── pyappcache ├── __init__.py ├── cache.py ├── compression.py ├── fs.py ├── keys.py ├── memcache.py ├── py.typed ├── redis.py ├── serialisation │ ├── __init__.py │ ├── core.py │ └── pandas.py ├── sqlite_lru.py └── util │ ├── __init__.py │ └── requests.py ├── pytest.ini ├── setup.py ├── tests ├── __init__.py ├── conftest.py ├── test-data │ └── stock-exchanges.parquet ├── test_caches.py ├── test_compression.py ├── test_keys.py ├── test_memcache.py ├── test_namespacing.py ├── test_redis.py ├── test_requests.py ├── test_serialisation.py ├── test_sqlite_lru.py └── utils.py └── tox.ini /.flake8: -------------------------------------------------------------------------------- 1 | [flake8] 2 | max-line-length = 88 3 | exclude=.mypy_cache,__pycache__,pyappcache.egg-info,build,dist,.tox,.coverage,htmlcov -------------------------------------------------------------------------------- /.github/workflows/ci.yml: -------------------------------------------------------------------------------- 1 | name: CI 2 | 3 | on: [push] 4 | 5 | jobs: 6 | build: 7 | runs-on: ubuntu-latest 8 | strategy: 9 | max-parallel: 4 10 | matrix: 11 | python-version: [3.8, 3.9, "3.10", "3.11", "3.12"] 12 | 13 | services: 14 | redis: 15 | image: redis 16 | ports: 17 | - 6379:6379 18 | options: --entrypoint redis-server 19 | 20 | memcached: 21 | image: memcached 22 | ports: 23 | - 11211:11211 24 | options: --entrypoint memcached 25 | 26 | steps: 27 | - uses: actions/checkout@v1 28 | - name: Set up Python ${{ matrix.python-version }} 29 | uses: actions/setup-python@v2 30 | with: 31 | python-version: ${{ matrix.python-version }} 32 | # pylibmc needs to build itself 33 | - name: Install dependencies 34 | run: | 35 | python -m pip install --upgrade pip 36 | pip install tox tox-gh-actions~=2.11.0 37 | sudo apt-get install libmemcached-dev 38 | - name: Test with tox 39 | run: tox 40 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | .mypy_cache 2 | __pycache__ 3 | pyappcache.egg-info 4 | build 5 | dist 6 | .tox 7 | .coverage 8 | htmlcov -------------------------------------------------------------------------------- /.readthedocs.yml: -------------------------------------------------------------------------------- 1 | --- 2 | 3 | version: 2 4 | 5 | python: 6 | version: 3.7 7 | install: 8 | - method: pip 9 | path: . 10 | extra_requirements: 11 | - tests 12 | -------------------------------------------------------------------------------- /CHANGELOG.md: -------------------------------------------------------------------------------- 1 | # Changelog 2 | 3 | ## 0.10.0 4 | ### Added 5 | 6 | - A new FilesystemCache 7 | - Added a new serialiser which uses Parquet instead of pickle for Pandas 8 | dataframes: `pyappcache.serialisation.pandas.DataFrameAwareSerialiser`. 9 | - Support for Python 3.12 10 | - A new `BinaryFileSerialiser` 11 | 12 | ### Changed 13 | 14 | - Caches now work on buffers internally, rather than strs 15 | - This is a breaking change for compressors and serialisers 16 | - This seems to work much better for larger values (eg dataframes, csv files, 17 | etc) 18 | - SqliteCache will now use [incremental blob 19 | I/O](https://www.sqlite.org/c3ref/blob.html) where possible (eg Python 3.11+) 20 | - Fixed an issue with the default prefix being "pyappache" 21 | - Sort out CacheControlProxy 22 | 23 | ### Removed 24 | 25 | - Support for Python 3.7 26 | 27 | ## 0.9.1 - 2022-12-08 28 | 29 | ### Added 30 | 31 | - `prefix` can be passed as an arg to `Cache.__init__` 32 | - Support up to Python 3.11 33 | 34 | ### Changed 35 | 36 | - Added a better repr for `SimpleStringKey` 37 | - Fixed two issues in sqlite where expiry and eviction were not correct 38 | 39 | ### Removed 40 | 41 | - Support for Python 3.6 42 | 43 | ## 0.9 - 2021-03-01 44 | 45 | ### Added 46 | 47 | - Improved documentation greatly (and put it on RTD) 48 | - GPLv3 license 49 | 50 | ### Changed 51 | 52 | - Change the Key classes, a breaking change 53 | 54 | ### Removed 55 | 56 | ## 0.2 - 2021-01-14 57 | 58 | ### Added 59 | - Support for operating as a read-through/write-through cache 60 | - `get_via` (update-on-read) 61 | - `set_via` (update-on-write) 62 | - Key "namespacing" (documentation to follow) 63 | 64 | ### Changed 65 | - pylibmc and redis are now optional dependencies 66 | - eg install `pyappcache[memcache]` or `pyappcache[redis]` to require them 67 | - Default cache prefix is now just "pyappcache" and slashes are added when building raw keys 68 | - The required API surface of caches has been reduced further 69 | - MemcacheCache will retry exactly once when pylibmc raises a ConnectionError 70 | - in order to be robust against memcache restarts 71 | 72 | ### Removed 73 | - repr no longer defined on GenericStringKey 74 | 75 | ## 0.1 - 2020-07-15 76 | 77 | - First version 78 | -------------------------------------------------------------------------------- /COPYING: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /MANIFEST.in: -------------------------------------------------------------------------------- 1 | include COPYING -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | # Minimal makefile for Sphinx documentation 2 | # 3 | 4 | # You can set these variables from the command line, and also 5 | # from the environment for the first two. 6 | SPHINXOPTS ?= 7 | SPHINXBUILD ?= sphinx-build 8 | SOURCEDIR = source 9 | BUILDDIR = build 10 | 11 | # Put it first so that "make" without argument is like "make help". 12 | help: 13 | @$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O) 14 | 15 | .PHONY: help Makefile 16 | 17 | # Catch-all target: route all unknown targets to Sphinx using the new 18 | # "make mode" option. $(O) is meant as a shortcut for $(SPHINXOPTS). 19 | %: Makefile 20 | @$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O) 21 | -------------------------------------------------------------------------------- /README.rst: -------------------------------------------------------------------------------- 1 | pyappcache 2 | ========== 3 | 4 | Pyappcache is a library to make it easier to use application-level 5 | caching in Python. 6 | 7 | - Allows putting arbitrary Python objects into the cache 8 | - Uses PEP484 type hints to help you typecheck cache return values 9 | - Supports Memcache, Redis and SQLite 10 | - Supports working as a "read-through" and "write-through" cache 11 | - Native support for key `"namespacing" `__ 12 | - Provides a few handy extras 13 | 14 | - A plugin for the 15 | `cachecontrol `__ library 16 | so you can also use it as an HTTP cache with 17 | `requests `__ 18 | 19 | A simple example 20 | ---------------- 21 | 22 | .. code:: python 23 | 24 | from datetime import date 25 | 26 | from pyappcache.redis import RedisCache 27 | from pyappcache.keys import Key, SimpleStringKey 28 | 29 | cache = RedisCache() 30 | 31 | # Annotate the type here to let mypy know this key is used for dates 32 | key: Key[date] = SimpleStringKey("mifid start date") 33 | cache.set(key, date(2018, 1, 3), ttl_seconds=3600) 34 | 35 | ... # later... 36 | 37 | # This variable's type will be inferred as datetime.date 38 | special_date = cache.get(key) 39 | 40 | 41 | How it compares to alternatives 42 | ------------------------------- 43 | 44 | Using the redis/memcache/sqlite client directly 45 | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 46 | 47 | - Explicit key objects allow for type inference and encapsulation of keying 48 | - Keys are prefix to help prevent collisions 49 | - Optional, pluggable, compression 50 | - Hopefully the overhead is small (not yet tested!) 51 | - Portable between redis/memcache/sqlite, etc 52 | 53 | dogpile.cache 54 | ~~~~~~~~~~~~~ 55 | 56 | - Explicit key objects allow for type inference and encapsulation of keying 57 | - dogpile.cache provides locking, pyappcache does not 58 | - Reduced temptation to use the problematic decorator pattern 59 | - This often causes import order problems as you need to have your cache at import time 60 | - Pyappache doesn't provide DBM/file backends, SQLite instead 61 | -------------------------------------------------------------------------------- /VERSION: -------------------------------------------------------------------------------- 1 | 0.10.0 -------------------------------------------------------------------------------- /docs/_static/.gitignore: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/calpaterson/pyappcache/f4bff4f8d522c6103e378be32b97e35bff116f36/docs/_static/.gitignore -------------------------------------------------------------------------------- /docs/caches.rst: -------------------------------------------------------------------------------- 1 | Caches 2 | ====== 3 | 4 | The standard interface 5 | ---------------------- 6 | 7 | Pyappcache supports multiple different cache backends, all with the same 8 | interface. No matter whether you're using Redis, Memcache or the SQLiteCache 9 | you will use the same interface: 10 | 11 | .. autoclass:: pyappcache.cache.Cache 12 | :members: get, set, invalidate, clear, set_by_str, get_by_str, 13 | invalidate_by_str, prefix, compressor, serialiser 14 | 15 | 16 | 17 | Redis 18 | ~~~~~ 19 | 20 | .. autoclass:: pyappcache.redis.RedisCache 21 | :members: __init__ 22 | 23 | Memcache 24 | ~~~~~~~~ 25 | 26 | .. autoclass:: pyappcache.memcache.MemcacheCache 27 | :members: __init__ 28 | 29 | SqliteCache 30 | ~~~~~~~~~~~ 31 | 32 | Pyappcache also includes a Sqlite-based implementation of an LRU cache. This 33 | can be handy for scripts. 34 | 35 | .. autoclass:: pyappcache.sqlite_lru.SqliteCache 36 | :members: __init__ 37 | 38 | .. autofunction:: pyappcache.sqlite_lru.get_in_memory_conn 39 | 40 | See :ref:`local sqlite file as cache` for the common pattern of storing the 41 | cache in a file alongside a script. 42 | 43 | Implementing support for a custom cache backend 44 | ----------------------------------------------- 45 | 46 | If you use something else as a cache (a filesystem, some SQL database, dbm) 47 | implementing a custom driver is not too hard. 48 | 49 | You need only subclass :class:`~pyappcache.cache.Cache` and implement four 50 | abstract methods: 51 | 52 | .. automethod:: pyappcache.cache.Cache.get_raw 53 | 54 | .. automethod:: pyappcache.cache.Cache.set_raw 55 | 56 | .. automethod:: pyappcache.cache.Cache.invalidate_raw 57 | 58 | .. automethod:: pyappcache.cache.Cache.clear 59 | :noindex: 60 | 61 | :class:`~pyappcache.cache.Cache` is implemented entirely in terms of these four 62 | methods so once you implement these, you get everything else "for free". 63 | -------------------------------------------------------------------------------- /docs/common_patterns.rst: -------------------------------------------------------------------------------- 1 | Common patterns 2 | =============== 3 | 4 | Using pyappcache to provide caching for ``requests`` 5 | ---------------------------------------------------- 6 | 7 | Pyappcache provides some added extras to allow it to be used as a cache for the 8 | popular `requests `_ library when 9 | used in conjunction with the `CacheControl 10 | `_ library. 11 | 12 | CacheControl provides the HTTP caching logic and Pyappcache provides the cache 13 | backends. 14 | 15 | .. autoclass:: pyappcache.util.requests.CacheControlProxy 16 | 17 | .. code:: python 18 | 19 | import requests 20 | import cachecontrol 21 | from pyappcache.redis import RedisCache 22 | from pyappcache.util.requests import CacheControlProxy 23 | 24 | # Create a Cache instance around Redis 25 | cache = RedisCache() 26 | 27 | # Create the proxy, which implements CacheControl's desired API 28 | cc_proxy = CacheControlProxy(cache) 29 | 30 | # Create the session 31 | cached_session = cachecontrol.CacheControl( 32 | requests.Session(), 33 | cache=cc_proxy 34 | ) 35 | 36 | # Make the request - first time not cached 37 | cached_session.get("http://calpaterson.com") 38 | 39 | # Make the request - seen it before so reads from cache 40 | cached_session.get("http://calpaterson.com") 41 | 42 | 43 | Storing your cache in a local sqlite file 44 | ----------------------------------------- 45 | 46 | .. _local sqlite file as cache: 47 | 48 | Sometimes it's handy to have the cache stored on disk. This is not as fast as 49 | in-memory but can be handy if you need a way to persist cache entries but 50 | aren't able to run a "proper" cache server like memcache or redis. 51 | 52 | .. code:: python 53 | 54 | import sqlite3 55 | from pyappcache.sqlite_lru import SqliteCache 56 | 57 | sqlite_db = sqlite3.connect("my_cache.sqlite3") 58 | cache = SqliteCache(connection=sqlite_db) 59 | -------------------------------------------------------------------------------- /docs/compression_and_serialisation.rst: -------------------------------------------------------------------------------- 1 | Compression and serialisation 2 | ============================== 3 | 4 | Pyappcache offers pluggable compression and serialisation so you can choose 5 | what is used to compress your cache values and how they are serialised. The 6 | defaults are gzip and pickle. 7 | 8 | Compression 9 | ----------- 10 | 11 | .. autoclass:: pyappcache.compression.Compressor 12 | :members: is_compressed, compress, decompress 13 | 14 | .. autoclass:: pyappcache.compression.GZIPCompressor 15 | :members: level 16 | 17 | 18 | Serialisation 19 | ------------- 20 | 21 | .. autoclass:: pyappcache.serialisation.Serialiser 22 | :members: dumps, loads 23 | 24 | .. autoclass:: pyappcache.serialisation.PickleSerialiser 25 | :members: pickle_protocol 26 | -------------------------------------------------------------------------------- /docs/conf.py: -------------------------------------------------------------------------------- 1 | # Configuration file for the Sphinx documentation builder. 2 | # 3 | # This file only contains a selection of the most common options. For a full 4 | # list see the documentation: 5 | # https://www.sphinx-doc.org/en/master/usage/configuration.html 6 | 7 | # -- Path setup -------------------------------------------------------------- 8 | 9 | # If extensions (or modules to document with autodoc) are in another directory, 10 | # add these directories to sys.path here. If the directory is relative to the 11 | # documentation root, use os.path.abspath to make it absolute, like shown here. 12 | # 13 | # import os 14 | # import sys 15 | # sys.path.insert(0, os.path.abspath('.')) 16 | 17 | 18 | # -- Project information ----------------------------------------------------- 19 | 20 | project = "pyappcache" 21 | copyright = "2020, Cal Paterson" 22 | author = "Cal Paterson" 23 | 24 | 25 | # -- General configuration --------------------------------------------------- 26 | 27 | # Add any Sphinx extension module names here, as strings. They can be 28 | # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom 29 | # ones. 30 | extensions = [ 31 | "sphinx.ext.autodoc", 32 | "sphinx_autodoc_typehints", 33 | ] 34 | 35 | # Add any paths that contain templates here, relative to this directory. 36 | templates_path = ["_templates"] 37 | 38 | # List of patterns, relative to source directory, that match files and 39 | # directories to ignore when looking for source files. 40 | # This pattern also affects html_static_path and html_extra_path. 41 | exclude_patterns = [] # type: ignore 42 | 43 | 44 | # -- Options for HTML output ------------------------------------------------- 45 | 46 | # The theme to use for HTML and HTML Help pages. See the documentation for 47 | # a list of builtin themes. 48 | # 49 | html_theme = "alabaster" 50 | 51 | # Add any paths that contain custom static files (such as style sheets) here, 52 | # relative to this directory. They are copied after the builtin static files, 53 | # so a file named "default.css" will overwrite the builtin "default.css". 54 | html_static_path = ["_static"] 55 | 56 | master_doc = "index" 57 | 58 | autodoc_member_order = "bysource" 59 | -------------------------------------------------------------------------------- /docs/index.rst: -------------------------------------------------------------------------------- 1 | pyappcache documentation 2 | ======================== 3 | 4 | pyappcache is a Python library for using volatile caches such as memcache or 5 | redis. 6 | 7 | A minimal example using Redis 8 | ----------------------------- 9 | 10 | .. code:: python 11 | 12 | from datetime import date 13 | 14 | from pyappcache.redis import RedisCache 15 | from pyappcache.keys import Key, SimpleStringKey 16 | 17 | cache = RedisCache() 18 | 19 | # Annotate the type here to let mypy know this key is used for dates 20 | key: Key[date] = SimpleStringKey("mifid start date") 21 | cache.set(key, date(2018, 1, 3), ttl_seconds=3600) 22 | 23 | ... # later... 24 | 25 | # This variable's type will be inferred as datetime.date 26 | special_date = cache.get(key) 27 | 28 | The above code: 29 | 30 | - creates a new instance of pyappcache's `RedisCache` class 31 | - creates a new key object 32 | - sets that key's value to `date(2018, 1, 3)` 33 | - and then (later) that value can be retrieved *with the right type inference* 34 | 35 | 36 | Reference documentation 37 | ----------------------- 38 | 39 | .. toctree:: 40 | :maxdepth: 3 41 | 42 | caches 43 | keys 44 | compression_and_serialisation 45 | common_patterns 46 | rationale 47 | 48 | 49 | Indices and tables 50 | ================== 51 | 52 | * :ref:`genindex` 53 | * :ref:`modindex` 54 | * :ref:`search` 55 | -------------------------------------------------------------------------------- /docs/keys.rst: -------------------------------------------------------------------------------- 1 | Keys 2 | ==== 3 | 4 | Why Key classes? 5 | ---------------- 6 | 7 | The advantage of making cache keys first class objects: 8 | 9 | #. Encapsulate all the logic for calculating the key in one place 10 | #. Allow for typechecking return values from the cache 11 | #. Make it possible to control compression, namespacing, etc in one place 12 | 13 | A note on "key paths" 14 | ^^^^^^^^^^^^^^^^^^^^^ 15 | 16 | Pyappcache is designed around the idea of "key paths" that are predictable and 17 | similar to unix paths, such as `users/54/likes`, which might store user number 18 | 54's likes. Predictable key paths aid debugging - you can always guess where 19 | to look when using the cache separately from pyappcache. 20 | 21 | Pyappcache caches will also *prefix* key paths with some custom key path, to 22 | allow multiple different uses of the same cache without each clobbering the 23 | other's namespace. 24 | 25 | How to create your own key classes 26 | ---------------------------------- 27 | 28 | Three different ways, from most straightforward to most complex. 29 | 30 | Option 1: Simple string keys 31 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 32 | 33 | If you just want to use a string as your key, you can use 34 | :class:`~pyappcache.keys.SimpleStringKey` directly. 35 | 36 | .. autoclass:: pyappcache.keys.SimpleStringKey 37 | :members: __init__ 38 | 39 | .. code:: python 40 | 41 | from pyappcache.keys import SimpleStringKey 42 | 43 | death_star_location = SimpleStringKey("death-star-location") 44 | cache.set(death_star_location, "near alderaan") 45 | 46 | ... # later... 47 | where_is_it_now = cache.get(death_star_location) 48 | 49 | Option 2: Subclasses of BaseKey 50 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 51 | 52 | If you want to have something more complicated, you can often get started by 53 | subclassing :class:`~pyappcache.keys.BaseKey`. 54 | 55 | .. autoclass:: pyappcache.keys.BaseKey 56 | :members: cache_key_segments 57 | 58 | This abstract base class is designed to make it quick as possible to create a 59 | new key class - just override `cache_key_segments` and you're ready to go. 60 | 61 | .. code:: python 62 | 63 | from pyappcache.keys import BaseKey 64 | from some_orm_layer import BigORMObj 65 | 66 | class BigORMObjKey(BaseKey): 67 | def __init__(self, big_orm_obj): 68 | self.big_orm_obj = big_orm_obj 69 | 70 | def cache_key_segments(self): 71 | return str(big_orm_obj.id) 72 | 73 | Option 3: Create your own Keys from scratch 74 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 75 | 76 | If you want full flexibilty you need only define three special methods to allow 77 | any object to act as a `Key`. 78 | 79 | .. autoclass:: pyappcache.keys.Key 80 | :members: namespace_key, should_compress, cache_key_segments 81 | -------------------------------------------------------------------------------- /docs/rationale.rst: -------------------------------------------------------------------------------- 1 | Rationale 2 | ========= 3 | 4 | Pyappcache takes a slightly different approach to other cache libraries. 5 | 6 | First class key objects 7 | ----------------------- 8 | 9 | In pyappcache, keys are first class objects - though you can use strings too if 10 | you prefer. 11 | 12 | Make keys a first class object to make it easier to centralise logic around 13 | keying and avoid typos and other common mistakes that arise when using strings 14 | as keys. 15 | 16 | Support multiple caches 17 | ----------------------- 18 | 19 | Redis and Memcache are both popular volatile caches. Pyappcache also includes 20 | an implementation using Sqlite can be useful in some scenarios. 21 | 22 | It's also easy(ish) to implement support for a new cache. 23 | 24 | Support type hints 25 | ------------------ 26 | 27 | Pyappcache has type hinting to help catch bugs - particularly the common 28 | mistake of forgetting that the cache might return nothing! 29 | 30 | Pluggable serialisation and compression 31 | --------------------------------------- 32 | 33 | The specifics of how Python objects are turned into bytestrings is explicit and 34 | pluggable - you can provide your own compression and serialisation methods. 35 | 36 | Inspectable 37 | ----------- 38 | 39 | Pyappcache generates predictable cache keys to make debugging easier - you'll 40 | be able to predict what key is generated (and if you don't know, you can ask a 41 | key object in a REPL). 42 | -------------------------------------------------------------------------------- /make.bat: -------------------------------------------------------------------------------- 1 | @ECHO OFF 2 | 3 | pushd %~dp0 4 | 5 | REM Command file for Sphinx documentation 6 | 7 | if "%SPHINXBUILD%" == "" ( 8 | set SPHINXBUILD=sphinx-build 9 | ) 10 | set SOURCEDIR=source 11 | set BUILDDIR=build 12 | 13 | if "%1" == "" goto help 14 | 15 | %SPHINXBUILD% >NUL 2>NUL 16 | if errorlevel 9009 ( 17 | echo. 18 | echo.The 'sphinx-build' command was not found. Make sure you have Sphinx 19 | echo.installed, then set the SPHINXBUILD environment variable to point 20 | echo.to the full path of the 'sphinx-build' executable. Alternatively you 21 | echo.may add the Sphinx directory to PATH. 22 | echo. 23 | echo.If you don't have Sphinx installed, grab it from 24 | echo.http://sphinx-doc.org/ 25 | exit /b 1 26 | ) 27 | 28 | %SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O% 29 | goto end 30 | 31 | :help 32 | %SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O% 33 | 34 | :end 35 | popd 36 | -------------------------------------------------------------------------------- /mypy.ini: -------------------------------------------------------------------------------- 1 | [mypy] 2 | python_version = 3.8 3 | exclude = ["build"] 4 | 5 | check_untyped_defs = True 6 | no_implicit_optional = True 7 | warn_unused_configs = True 8 | # currently there is a discrepency between types for requests between python 9 | # versions 10 | # warn_unused_ignores = True 11 | disallow_incomplete_defs = True 12 | warn_return_any = True 13 | strict_equality = True 14 | [mypy-setuptools] 15 | ignore_missing_imports = True 16 | [mypy-pylibmc.*] 17 | ignore_missing_imports = True 18 | [mypy-pytest.*] 19 | ignore_missing_imports = True 20 | [mypy-responses.*] 21 | ignore_missing_imports = True 22 | [mypy-cachecontrol.*] 23 | ignore_missing_imports = True 24 | [mypy-pluggy] 25 | ignore_missing_imports = True 26 | [mypy-exceptiongroup] 27 | ignore_missing_imports = True 28 | [mypy-tomli] 29 | ignore_missing_imports = True -------------------------------------------------------------------------------- /pyappcache/__init__.py: -------------------------------------------------------------------------------- 1 | # 2 | -------------------------------------------------------------------------------- /pyappcache/cache.py: -------------------------------------------------------------------------------- 1 | from abc import ABCMeta, abstractmethod 2 | from logging import getLogger 3 | from typing import Optional, TypeVar, Any, cast, Callable, Sequence, Mapping, IO 4 | 5 | from .compression import Compressor, GZIPCompressor 6 | from .serialisation import Serialiser, PickleSerialiser 7 | from .keys import Key, build_raw_key 8 | 9 | V = TypeVar("V") 10 | 11 | 12 | logger = getLogger(__name__) 13 | 14 | 15 | class Cache(metaclass=ABCMeta): 16 | """The standard, cross backend, interface to a cache.""" 17 | 18 | DEFAULT_PREFIX = "pyappcache" 19 | 20 | def __init__(self, prefix=DEFAULT_PREFIX): 21 | #: A prefix that will be applied to cache keys to allow for multiple 22 | #: instances of this class to co-exist. Exact use varies by particular 23 | #: cache. Default is `'pyappcache'`. 24 | self.prefix = prefix 25 | #: The compressor that will be used when a key asks for compression. 26 | #: Default is gzip via :class:`.compression.GZIPCompressor` 27 | self.compressor: Compressor = GZIPCompressor() 28 | #: The serialiers that will be used to turn Python objects back and 29 | #: forth into bytes. The default serialiser is pickle, via 30 | #: :class:`.serialisation.PickleSerialiser` 31 | self.serialiser: Serialiser = PickleSerialiser() 32 | 33 | def get(self, key: Key[V]) -> Optional[V]: 34 | """Look up the value stored under a :class:`~pyappcache.keys.Key` instance""" 35 | namespace_key = key.namespace_key() 36 | if namespace_key is not None: 37 | namespace = self.lookup_namespace(namespace_key) 38 | if namespace is None: 39 | return None 40 | else: 41 | namespace = None 42 | 43 | cache_contents = self.get_raw( 44 | build_raw_key(self.prefix, key, namespace=namespace) 45 | ) 46 | if cache_contents is not None: 47 | if self.compressor.is_compressed(cache_contents): 48 | cache_contents = self.compressor.decompress(cache_contents) 49 | return cast(V, self.serialiser.load(cache_contents)) 50 | else: 51 | return None 52 | 53 | def get_by_str(self, key_str: str) -> Optional[Any]: 54 | """Look up the value stored under a :class:`str`. 55 | 56 | Users of this method will have to construct string keys for themselves.""" 57 | cache_contents = self.get_raw(build_raw_key(self.prefix, key_str)) 58 | if cache_contents is not None: 59 | if self.compressor.is_compressed(cache_contents): 60 | cache_contents = self.compressor.decompress(cache_contents) 61 | return self.serialiser.load(cache_contents) 62 | else: 63 | return None 64 | 65 | def get_via(self, key: Key[V], getter: Callable[[], V]) -> V: 66 | cache_contents = self.get(key) 67 | if cache_contents is None: 68 | new_cache_contents = getter() 69 | self.set(key, new_cache_contents) 70 | return new_cache_contents 71 | else: 72 | return cache_contents 73 | 74 | def lookup_namespace(self, key: Key) -> Optional[str]: 75 | # FIXME: is this required? 76 | namespace = self.get(key) 77 | if namespace is not None: 78 | return str(namespace) 79 | else: 80 | return None 81 | 82 | def set(self, key: Key[V], value: V, ttl_seconds: int = 0) -> None: 83 | """Set a value by :class:`~pyappcache.keys.Key`""" 84 | namespace_key = key.namespace_key() # FIXME: move this inside lookup_namespace 85 | if namespace_key is not None: 86 | namespace = self.lookup_namespace(namespace_key) 87 | if namespace is None: 88 | logger.warning("unable to set key as namespace does not exist") 89 | return None 90 | else: 91 | namespace = None 92 | as_pickle = self.serialiser.dump(value) 93 | if key.should_compress(value, as_pickle): 94 | as_bytes = self.compressor.compress(as_pickle) 95 | else: 96 | as_bytes = as_pickle 97 | self.set_raw( 98 | build_raw_key(self.prefix, key, namespace=namespace), as_bytes, ttl_seconds 99 | ) 100 | 101 | def set_via( 102 | self, 103 | key: Key[V], 104 | value: V, 105 | setter: Callable[..., Any], 106 | setter_args: Sequence = (), 107 | setter_kwargs: Optional[Mapping] = None, 108 | ) -> None: 109 | if setter_kwargs is None: 110 | setter_kwargs = {} 111 | setter(*setter_args, **setter_kwargs) 112 | self.set(key, value) 113 | 114 | def set_by_str( 115 | self, key_str: str, value: V, ttl_seconds: int = 0, compress: bool = False 116 | ) -> None: 117 | """Set a value by a :class:`str`.""" 118 | as_pickle = self.serialiser.dump(value) 119 | if compress: 120 | as_bytes = self.compressor.compress(as_pickle) 121 | else: 122 | as_bytes = as_pickle 123 | raw_key = build_raw_key(self.prefix, key_str) 124 | self.set_raw( 125 | raw_key, 126 | as_bytes, 127 | ttl_seconds, 128 | ) 129 | 130 | def invalidate(self, key: Key[V]) -> None: 131 | """Invalidate by :class:`~pyappcache.keys.Key`. 132 | 133 | Depending on the particular implementation of invalidation this may or 134 | may not immediately free memory in the underlying cache (usually not).""" 135 | namespace_key = key.namespace_key() # FIXME: move this inside lookup_namespace 136 | if namespace_key is not None: 137 | namespace = self.lookup_namespace(namespace_key) 138 | if namespace is None: 139 | logger.warning("unable to invalidate key as namespace does not exist") 140 | return None 141 | else: 142 | namespace = None 143 | self.invalidate_raw(build_raw_key(self.prefix, key, namespace=namespace)) 144 | 145 | def invalidate_by_str(self, key_str: str) -> None: 146 | self.invalidate_raw(build_raw_key(self.prefix, key_str)) 147 | 148 | @abstractmethod 149 | def get_raw(self, key_str: str) -> Optional[IO[bytes]]: 150 | """Look up a value (as bytes) from a concrete key string. 151 | 152 | :param key_str: the (fully prefixed) key string to look up 153 | 154 | """ 155 | pass # pragma: no cover 156 | 157 | @abstractmethod 158 | def set_raw(self, key_str: str, value_bytes: IO[bytes], ttl_seconds: int) -> None: 159 | """Set a value (as bytes) by a concrete key string. 160 | 161 | :param key_str: the (fully prefixed) key string to set. 162 | """ 163 | pass # pragma: no cover 164 | 165 | @abstractmethod 166 | def invalidate_raw(self, key_str: str) -> None: 167 | """Invalidate a key by a concrete key string. 168 | 169 | :param key_str: the (fully prefixed) key string to invalidate 170 | """ 171 | pass # pragma: no cover 172 | 173 | @abstractmethod 174 | def clear(self) -> None: 175 | """Remove all keys from the cache. 176 | 177 | For most caches this will remove absolutely everything from the 178 | server, so use with care. 179 | 180 | """ 181 | pass # pragma: no cover 182 | -------------------------------------------------------------------------------- /pyappcache/compression.py: -------------------------------------------------------------------------------- 1 | from io import BytesIO 2 | import shutil 3 | from typing import IO, cast 4 | import gzip 5 | 6 | from typing_extensions import Protocol 7 | 8 | 9 | class Compressor(Protocol): 10 | """The protocol for compressors to follow""" 11 | 12 | def is_compressed(self, data: IO[bytes]) -> bool: 13 | """Takes some, possibly compressed data as an argument and returns True 14 | if is has been compressed with this compressor, False otherwise.""" 15 | pass # pragma: no cover 16 | 17 | def compress(self, data: IO[bytes]) -> IO[bytes]: 18 | """Compress the given bytes with this compressor""" 19 | pass # pragma: no cover 20 | 21 | def decompress(self, data: IO[bytes]) -> IO[bytes]: 22 | """Decompress the given bytes with this compressor""" 23 | pass # pragma: no cover 24 | 25 | 26 | class GZIPCompressor: 27 | """A default compressor that is gzip at level 5.""" 28 | 29 | def __init__(self, level: int = 5): 30 | """ 31 | 32 | :param level: The gzip compression level (default 5)""" 33 | #: Gzip compression level 34 | self.level = level 35 | 36 | def is_compressed(self, data: IO[bytes]) -> bool: 37 | head = data.read(2) 38 | data.seek(0) 39 | return head == b"\x1f\x8b" 40 | 41 | def compress(self, data: IO[bytes]) -> IO[bytes]: 42 | inner_buf = BytesIO() 43 | with gzip.GzipFile( 44 | fileobj=inner_buf, mode="w", compresslevel=self.level 45 | ) as gzip_f: 46 | shutil.copyfileobj(data, gzip_f) 47 | inner_buf.seek(0) 48 | return inner_buf 49 | 50 | def decompress(self, data: IO[bytes]) -> IO[bytes]: 51 | return cast(IO[bytes], gzip.open(data)) 52 | -------------------------------------------------------------------------------- /pyappcache/fs.py: -------------------------------------------------------------------------------- 1 | import os 2 | import sqlite3 3 | from typing import Optional, IO, List 4 | from logging import getLogger 5 | from pathlib import Path 6 | import shutil 7 | from contextlib import closing 8 | from datetime import datetime, timedelta 9 | 10 | from dateutil.parser import parse as parse_dt 11 | 12 | from .cache import Cache 13 | 14 | logger = getLogger(__name__) 15 | 16 | CREATE_DDL = """ 17 | CREATE TABLE IF NOT EXISTS pyappcache ( 18 | key PRIMARY KEY, 19 | expiry NOT NULL, 20 | last_read NOT NULL, 21 | size NOT NULL 22 | ); 23 | """ 24 | 25 | INDEX_DDL: List[str] = [ 26 | "CREATE INDEX IF NOT EXISTS idx_pyappcache_expiry ON pyappcache(expiry);", 27 | "CREATE INDEX IF NOT EXISTS idx_pyappcache_last_read ON pyappcache(last_read);", 28 | "CREATE INDEX IF NOT EXISTS idx_pyappcache_size ON pyappcache(size);", 29 | ] 30 | 31 | 32 | TOUCH_DML = """ 33 | UPDATE pyappcache 34 | SET last_read = ? 35 | WHERE key = ? 36 | AND (expiry >= ? OR expiry = '-1'); 37 | """ 38 | 39 | SET_DML = """ 40 | INSERT OR REPLACE INTO pyappcache 41 | (key, expiry, last_read, size) 42 | VALUES 43 | (?, ?, ?, ?); 44 | """ 45 | 46 | GET_TTL_DQL = """ 47 | SELECT expiry 48 | FROM pyappcache 49 | WHERE key = ?; 50 | """ 51 | 52 | # The below SQL should be done in one step using the RETURNING clause of the 53 | # DELETE statement, but RETURNING was only added to sqlite in 3.35.0 54 | # (2021-03-12) and not everyone has it yet (including me) 55 | 56 | GET_EVICTION_COHORT_DQL = """ 57 | SELECT 58 | KEY 59 | FROM ( 60 | SELECT 61 | KEY, 62 | last_read, 63 | SUM(size) OVER (ORDER BY last_read DESC) AS total_size 64 | FROM pyappcache) AS t 65 | WHERE 66 | total_size > ?; 67 | """ 68 | 69 | EVICT_COHORT_DML = """ 70 | DELETE FROM pyappcache 71 | WHERE KEY IN ( 72 | SELECT 73 | KEY 74 | FROM ( 75 | SELECT 76 | KEY, 77 | last_read, 78 | SUM(size) OVER (ORDER BY last_read DESC) AS total_size 79 | FROM pyappcache) AS t 80 | WHERE 81 | total_size > ? 82 | ) 83 | """ 84 | 85 | CLEAR_DML = """ 86 | UPDATE pyappcache SET expiry = ?; 87 | """ 88 | 89 | 90 | class FilesystemCache(Cache): 91 | METADATA_DB_FILENAME = "metadata.sqlite3" 92 | 93 | # 100mb default limit 94 | DEFAULT_MAX_SIZE = 1000 * 1000 * 100 95 | 96 | def __init__(self, directory: Path, max_size_bytes: int = DEFAULT_MAX_SIZE): 97 | super().__init__() 98 | self.directory = directory 99 | self.directory.mkdir(parents=True, exist_ok=True) 100 | self.max_size_bytes = max_size_bytes 101 | self.metadata_conn = sqlite3.connect( 102 | str(self.directory / self.METADATA_DB_FILENAME) 103 | ) 104 | with closing(self.metadata_conn.cursor()) as cursor: 105 | cursor.execute(CREATE_DDL) 106 | for index_ddl in INDEX_DDL: 107 | cursor.execute(index_ddl) 108 | self.metadata_conn.commit() 109 | 110 | def _make_path(self, raw_key: str) -> Path: 111 | path = self.directory / raw_key.replace("/", "_") 112 | path.parent.mkdir(parents=True, exist_ok=True) 113 | return path 114 | 115 | def get_raw(self, raw_key: str) -> Optional[IO[bytes]]: 116 | now = datetime.utcnow() 117 | with closing(self.metadata_conn.cursor()) as cursor: 118 | cursor.execute(TOUCH_DML, (now.isoformat(), raw_key, now.isoformat())) 119 | if cursor.rowcount == 0: 120 | return None 121 | self.metadata_conn.commit() 122 | 123 | path = self._make_path(raw_key) 124 | try: 125 | return path.open("rb") 126 | except FileNotFoundError: 127 | # FIXME: should handle this by expiring the key 128 | return None 129 | 130 | def set_raw(self, raw_key: str, value_bytes: IO[bytes], ttl_seconds: int) -> None: 131 | path = self._make_path(raw_key) 132 | with path.open("w+b") as fh: 133 | shutil.copyfileobj(value_bytes, fh) 134 | size = _get_fh_size(value_bytes) 135 | if ttl_seconds != 0: 136 | expiry = (datetime.utcnow() + timedelta(seconds=ttl_seconds)).isoformat() 137 | else: 138 | expiry = "-1" 139 | with closing(self.metadata_conn.cursor()) as cursor: 140 | cursor.execute(SET_DML, (raw_key, expiry, datetime.utcnow(), size)) 141 | self.metadata_conn.commit() 142 | self._evict() 143 | 144 | def invalidate_raw(self, raw_key: str) -> None: 145 | # FIXME: this should be updating the metadata 146 | path = self._make_path(raw_key) 147 | path.unlink(missing_ok=True) 148 | 149 | def _evict(self) -> None: 150 | """Evict data to maintain the maximum size.""" 151 | with closing(self.metadata_conn.cursor()) as cursor: 152 | cursor.execute("BEGIN;") 153 | cursor.execute(GET_EVICTION_COHORT_DQL, (self.max_size_bytes,)) 154 | rs = cursor.fetchall() 155 | cursor.execute(EVICT_COHORT_DML, (self.max_size_bytes,)) 156 | self.metadata_conn.commit() 157 | 158 | for row in rs: 159 | raw_key = row[0] 160 | path = self._make_path(raw_key) 161 | path.unlink(missing_ok=True) 162 | 163 | def ttl(self, key_bytes: str) -> Optional[int]: 164 | """Returns the (remaining) TTL of the given key.""" 165 | now = datetime.utcnow() 166 | with closing(self.metadata_conn.cursor()) as cursor: 167 | cursor.execute(GET_TTL_DQL, (key_bytes,)) 168 | row = cursor.fetchone() 169 | if row is not None: 170 | expiry = row[0] 171 | expiry_dt = parse_dt(expiry) 172 | ttl_td = expiry_dt - now 173 | return int(ttl_td.total_seconds()) 174 | else: 175 | return None 176 | 177 | def clear(self) -> None: 178 | now = datetime.utcnow() 179 | past = now - timedelta(seconds=1) 180 | with closing(self.metadata_conn.cursor()) as cursor: 181 | cursor.execute(CLEAR_DML, (past.isoformat(),)) 182 | self.metadata_conn.commit() 183 | 184 | 185 | def _get_fh_size(fh: IO[bytes]) -> int: 186 | """Return the size of a seekable binary filehandle.""" 187 | pos = fh.tell() 188 | fh.seek(0, os.SEEK_END) 189 | size = fh.tell() 190 | fh.seek(pos) 191 | return size 192 | -------------------------------------------------------------------------------- /pyappcache/keys.py: -------------------------------------------------------------------------------- 1 | from abc import abstractmethod, ABCMeta 2 | from typing import IO 3 | 4 | from typing import TypeVar, Sequence, Union, Optional, Any 5 | from typing_extensions import Protocol 6 | 7 | #: Key value 8 | V = TypeVar("V", contravariant=True) 9 | 10 | 11 | class Key(Protocol[V]): 12 | """The "protocol" for keys. Define the same methods as this class, and you 13 | have created a key which will work with pyappcache. 14 | 15 | """ 16 | 17 | def namespace_key(self) -> "Optional[Key[Any]]": 18 | """If this is a namespaced key, this method returns the key to the 19 | namespace that should be used - otherwise None. 20 | 21 | """ 22 | pass # pragma: no cover 23 | 24 | def should_compress(self, python_obj: V, as_bytes: IO[bytes]) -> bool: 25 | """This method passes the original Python object and the serialised 26 | `bytes` version of it in order to allow this method to decide whether 27 | compression should be used. 28 | 29 | This allows for this method to take Python level attributes/methods and 30 | the size of the bytestring into account when making a decision. 31 | 32 | Returns True if compression should be applied, False if not. 33 | """ 34 | pass # pragma: no cover 35 | 36 | def cache_key_segments(self) -> Sequence[str]: 37 | """Return segments of the whole key path. For example `["a", "b", 38 | "c"]` - the key segments will be prepended with the Cache's own 39 | :attr:`~pyappcache.cache.Cache.prefix` and then joined with slashes, 40 | similar to unix paths.""" 41 | pass # pragma: no cover 42 | 43 | 44 | class BaseKey(Key[V], metaclass=ABCMeta): 45 | """An abstract baseclass suitable (but not required) for subclassing to 46 | create many class:`~Key` instances. 47 | 48 | To use, subclass and override :meth:`~cache_key_segments`. To get 49 | progressively more functionality, you can also override 50 | :meth:`~namespace_key` and :meth:`should_compress`. 51 | 52 | """ 53 | 54 | def namespace_key(self) -> Optional[Key[Any]]: 55 | return None 56 | 57 | def should_compress(self, python_obj: V, as_bytes: IO[bytes]) -> bool: 58 | return False 59 | 60 | @abstractmethod 61 | def cache_key_segments(self) -> Sequence[str]: 62 | ... # pragma: no cover 63 | 64 | 65 | class SimpleStringKey(Key[V]): 66 | """A simple, string-based Key.""" 67 | 68 | def __init__(self, key_str: str): 69 | """Create a key based on a string""" 70 | self.key_str = key_str 71 | 72 | def namespace_key(self) -> Optional[Key[Any]]: 73 | return None 74 | 75 | def should_compress(self, python_obj: V, as_bytes: IO[bytes]) -> bool: 76 | return False 77 | 78 | def cache_key_segments(self) -> Sequence[str]: 79 | return [self.key_str] 80 | 81 | def __repr__(self) -> str: 82 | return f"" 83 | 84 | 85 | def build_raw_key( 86 | prefix: str, key: Union[Key, str], namespace: Optional[str] = None 87 | ) -> str: 88 | """Creates a string key from a cache prefix and a key, and optionally a 89 | resolved namespace. 90 | """ 91 | key_segments = [prefix] 92 | if namespace is not None: 93 | key_segments.append(namespace) 94 | if isinstance(key, str): 95 | key_segments.append(key) 96 | else: 97 | key_segments.extend(key.cache_key_segments()) 98 | key_str = "/".join(key_segments) 99 | return key_str 100 | -------------------------------------------------------------------------------- /pyappcache/memcache.py: -------------------------------------------------------------------------------- 1 | import pylibmc 2 | import io 3 | 4 | from typing import Optional, Any, IO 5 | from logging import getLogger 6 | 7 | from .cache import Cache 8 | 9 | logger = getLogger(__name__) 10 | 11 | 12 | class MemcacheCache(Cache): 13 | """An implementation of Cache for memcache. 14 | 15 | All methods in this class will retry exactly once when the underlying 16 | pylibmc client returns a ConnectionError (to be robust against memcache 17 | restarts. 18 | """ 19 | 20 | def __init__(self, client: Optional[Any] = None): 21 | """ 22 | 23 | :param client: A optional (pylibmc-compatible) memcache client to use.""" 24 | super().__init__() 25 | if client is not None: 26 | self._mc = client 27 | else: 28 | self._mc = pylibmc.Client(["127.0.0.1"], binary=True) 29 | 30 | def get_raw(self, raw_key: str) -> Optional[IO[bytes]]: 31 | try: 32 | value = self._mc.get(raw_key) 33 | except pylibmc.ConnectionError: 34 | logger.warning("got a connection error from pylibmc, retrying once") 35 | value = self._mc.get(raw_key) 36 | if value is not None: 37 | return io.BytesIO(value) 38 | else: 39 | return None 40 | 41 | def set_raw(self, raw_key: str, value_bytes: IO[bytes], ttl: int) -> None: 42 | # FIXME: check that keys don't include control characters or whitespace 43 | # Or add a note? 44 | try: 45 | self._mc.set(raw_key, value_bytes.read(), time=ttl) 46 | return 47 | except pylibmc.ConnectionError: 48 | logger.warning("got a connection error from pylibmc, retrying once") 49 | value_bytes.seek(0) 50 | self._mc.set(raw_key, value_bytes.read(), time=ttl) 51 | 52 | def invalidate_raw(self, raw_key: str) -> None: 53 | try: 54 | self._mc.delete(raw_key) 55 | except pylibmc.ConnectionError: 56 | logger.warning("got a connection error from pylibmc, retrying once") 57 | self._mc.delete(raw_key) 58 | 59 | def clear(self) -> None: 60 | """Clear the cache. 61 | 62 | Warning: memcache doesn't have a way to list keys so this clears 63 | everything!""" 64 | logger.warning("flushing memcache!") 65 | try: 66 | self._mc.flush_all() 67 | except pylibmc.ConnectionError: 68 | logger.warning("got a connection error from pylibmc, retrying once") 69 | self._mc.flush_all() 70 | -------------------------------------------------------------------------------- /pyappcache/py.typed: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/calpaterson/pyappcache/f4bff4f8d522c6103e378be32b97e35bff116f36/pyappcache/py.typed -------------------------------------------------------------------------------- /pyappcache/redis.py: -------------------------------------------------------------------------------- 1 | import io 2 | from typing import Optional, cast, IO 3 | from logging import getLogger 4 | 5 | import redis as redis_py 6 | 7 | from .cache import Cache 8 | 9 | logger = getLogger(__name__) 10 | 11 | 12 | class RedisCache(Cache): 13 | """A redis :class:`~pyappcache.cache.Cache` instance. 14 | 15 | This uses ``GET``/``SET``/``DELETE``. 16 | 17 | .. admonition:: :meth:`~Cache.clear` uses ``FLUSHDB`` 18 | 19 | The clear method for this implementation will call ``FLUSHDB`` - and so 20 | remove *everything* in the database. 21 | 22 | """ 23 | 24 | def __init__(self, client: Optional[redis_py.Redis] = None): 25 | """ 26 | 27 | :param client: A optional redis client to use. If one isn't provided 28 | database 0 on localhost is used.""" 29 | super().__init__() 30 | if client is not None: 31 | self._redis = client 32 | else: 33 | self._redis = redis_py.Redis() 34 | 35 | def get_raw(self, raw_key: str) -> Optional[IO[bytes]]: 36 | value = self._redis.get(raw_key) 37 | if value is not None: 38 | return io.BytesIO(cast(bytes, value)) 39 | else: 40 | return None 41 | 42 | def set_raw(self, raw_key: str, value_bytes: IO[bytes], ttl_seconds: int) -> None: 43 | self._redis.set( 44 | raw_key, value_bytes.read(), ex=ttl_seconds if ttl_seconds != 0 else None 45 | ) 46 | 47 | def invalidate_raw(self, raw_key: str) -> None: 48 | self._redis.delete(raw_key) 49 | 50 | def clear(self) -> None: 51 | self._redis.flushdb() 52 | -------------------------------------------------------------------------------- /pyappcache/serialisation/__init__.py: -------------------------------------------------------------------------------- 1 | from .core import PickleSerialiser, BinaryFileSerialiser, Serialiser # noqa 2 | 3 | __all__ = ["PickleSerialiser", "Serialiser", "BinaryFileSerialiser"] 4 | -------------------------------------------------------------------------------- /pyappcache/serialisation/core.py: -------------------------------------------------------------------------------- 1 | from typing import Any, IO 2 | from io import BytesIO 3 | import pickle 4 | from logging import getLogger 5 | 6 | from typing_extensions import Protocol 7 | 8 | logger = getLogger(__name__) 9 | 10 | 11 | class Serialiser(Protocol): 12 | """The protocol for serialisers to follow""" 13 | 14 | def dump(self, obj: Any) -> IO[bytes]: 15 | """Dumps an arbitrary Python object to a buffer""" 16 | pass # pragma: no cover 17 | 18 | def load(self, data: IO[bytes]) -> Any: 19 | """Restores an arbitrary Python object from bytes, *or `None` if the 20 | bytes don't make sense*.""" 21 | pass # pragma: no cover 22 | 23 | 24 | class PickleSerialiser: 25 | """A wrapper for pickling. 26 | 27 | The difference between this and pickle.load/pickle.dump is that 28 | ``PickleSerialiser`` returns None when it can't unpickle - to defend 29 | against unreadable cache values.""" 30 | 31 | #: The pickle protocol level (default 4). Changing this default value 32 | #: will be considered a breaking API change. 33 | pickle_protocol = 4 34 | 35 | def dump(self, obj: Any) -> IO[bytes]: 36 | buf = BytesIO() 37 | pickle.dump(obj, buf, protocol=self.pickle_protocol) 38 | buf.seek(0) 39 | return buf 40 | 41 | def load(self, data: IO[bytes]) -> Any: 42 | try: 43 | value = pickle.load(data) 44 | except pickle.UnpicklingError: 45 | logger.warning("unable to unpickle value") 46 | value = None 47 | return value 48 | 49 | 50 | class BinaryFileSerialiser: 51 | def dump(self, obj: Any) -> IO[bytes]: 52 | try: 53 | pos = obj.tell() 54 | s = obj.read(10) 55 | obj.seek(pos) 56 | if type(s) is not bytes: 57 | raise RuntimeError( 58 | "BinaryFileSerializer can only serialise binary files (got a string file)" 59 | ) 60 | else: 61 | return obj 62 | except AttributeError: 63 | raise RuntimeError( 64 | f"BinaryFileSerializer can only serialise files, but got a {type(obj)}" 65 | ) 66 | 67 | def load(self, data: IO[bytes]) -> IO[bytes]: 68 | return data 69 | -------------------------------------------------------------------------------- /pyappcache/serialisation/pandas.py: -------------------------------------------------------------------------------- 1 | from logging import getLogger 2 | 3 | logger = getLogger(__name__) 4 | 5 | from typing import Any, IO 6 | from io import BytesIO 7 | 8 | import pandas as pd 9 | 10 | from .core import PickleSerialiser 11 | 12 | 13 | class DataFrameAwareSerialiser(PickleSerialiser): 14 | """A serialiser that is aware of dataframes and, instead of pickling them, 15 | outputs them to parquet. 16 | 17 | """ 18 | 19 | def __init__(self): 20 | super().__init__() 21 | 22 | def dump(self, obj: Any) -> IO[bytes]: 23 | if isinstance(obj, pd.DataFrame): 24 | buf = BytesIO() 25 | obj.to_parquet(buf) 26 | buf.seek(0) 27 | return buf 28 | else: 29 | return super().dump(obj) 30 | 31 | def load(self, data: IO[bytes]) -> Any: 32 | if _is_parquet(data): 33 | return pd.read_parquet(data) 34 | else: 35 | return super().load(data) 36 | 37 | 38 | def _is_parquet(data: IO[bytes]) -> bool: 39 | head = data.read(3) 40 | data.seek(0) 41 | return head == b"PAR" 42 | -------------------------------------------------------------------------------- /pyappcache/sqlite_lru.py: -------------------------------------------------------------------------------- 1 | from typing import Optional, Union, IO 2 | import shutil 3 | import io 4 | from datetime import datetime, timedelta 5 | from contextlib import closing 6 | import sqlite3 7 | 8 | from dateutil.parser import parse as parse_dt 9 | 10 | from .cache import Cache 11 | 12 | CREATE_DDL = """ 13 | CREATE TABLE IF NOT EXISTS pyappcache 14 | (key PRIMARY KEY, value NOT NULL, expiry NOT NULL, last_read NOT NULL); 15 | """ 16 | 17 | INDEX_DDL = [ 18 | """ 19 | CREATE INDEX IF NOT EXISTS pyappcache_expiry 20 | ON pyappcache (expiry); 21 | """, 22 | """ 23 | CREATE INDEX IF NOT EXISTS pyappcache_last_read 24 | ON pyappcache (last_read); 25 | """, 26 | ] 27 | 28 | SET_DML = """ 29 | INSERT OR REPLACE INTO pyappcache 30 | (key, value, expiry, last_read) 31 | VALUES 32 | (?, ?, ?, ?); 33 | """ 34 | 35 | SET_DML_FOR_BLOBOPEN = """ 36 | INSERT OR REPLACE INTO pyappcache 37 | (key, value, expiry, last_read) 38 | VALUES 39 | (?, zeroblob(?), ?, ?); 40 | """ 41 | 42 | EVICT_DML = """ 43 | DELETE FROM pyappcache 44 | WHERE key IN ( 45 | SELECT key 46 | FROM pyappcache 47 | ORDER BY last_read DESC 48 | LIMIT -1 OFFSET ? 49 | ); 50 | """ 51 | 52 | TOUCH_DML = """ 53 | UPDATE pyappcache 54 | SET last_read = ? 55 | WHERE key = ? 56 | AND (expiry >= ? OR expiry = '-1'); 57 | """ 58 | 59 | GET_DQL = """ 60 | SELECT value 61 | FROM pyappcache 62 | WHERE key = ? 63 | AND (expiry >= ? OR expiry = '-1'); 64 | """ 65 | 66 | GET_DQL_FOR_BLOBOPEN = """ 67 | SELECT rowid 68 | FROM pyappcache 69 | WHERE key = ? 70 | AND (expiry >= ? OR expiry = '-1'); 71 | """ 72 | 73 | GET_TTL_DQL = """ 74 | SELECT expiry 75 | FROM pyappcache 76 | WHERE key = ?; 77 | """ 78 | 79 | INVALIDATE_DML = """ 80 | DELETE FROM pyappcache 81 | WHERE key = ?; 82 | """ 83 | 84 | CLEAR_DML = """ 85 | DELETE FROM pyappcache; 86 | """ 87 | 88 | # This is present as a basic safety feature - to prevent people blowing up 89 | # their processes by accident 90 | MAX_SIZE = 10_000 91 | 92 | 93 | _in_memory_conn = None 94 | 95 | 96 | def get_in_memory_conn(): 97 | """Get a shared in-memory connection. 98 | 99 | This is used by :class:`~pyappcache.sqlite_lru.SqliteCache` to get a named 100 | in-memory sqlite connection (`pyappcache_memory` - to avoid clobbering 101 | other users of in-memory sqlite databases) and multi-thread support. 102 | 103 | """ 104 | global _in_memory_conn 105 | if _in_memory_conn is None: 106 | # This avoids clobbering other in memory sqlite databases (but allows 107 | # us to use them from different threads) 108 | _in_memory_conn = sqlite3.connect( 109 | "file:pyappcache_memory?mode=memory&cache=shared" 110 | ) 111 | return _in_memory_conn 112 | 113 | 114 | class SqliteCache(Cache): 115 | """Implementation of an LRU cache using sqlite3. 116 | 117 | Note that as this is an LRU cache data accesses require write access (in 118 | order to update the last-used time). 119 | """ 120 | 121 | def __init__( 122 | self, max_size: int = MAX_SIZE, connection: Optional[sqlite3.Connection] = None 123 | ): 124 | """ 125 | 126 | :parameter max_size: Maximum size of the LRU cache. Defaults to 10,000 127 | :parameter connection: Optionally, you can pass a sqlite3 connection. By 128 | default an in-memory database will be used (this will be is shared between all 129 | instances). 130 | 131 | """ 132 | super().__init__() 133 | if connection is None: 134 | self.conn = get_in_memory_conn() 135 | else: 136 | self.conn = connection 137 | 138 | # the blobopen API is newish, 3.11+ 139 | self._has_blobopen = hasattr(self.conn, "blobopen") 140 | 141 | self.max_size = max_size 142 | with closing(self.conn.cursor()) as cursor: 143 | cursor.execute(CREATE_DDL) 144 | for index_ddl in INDEX_DDL: 145 | cursor.execute(index_ddl) 146 | self.conn.commit() 147 | 148 | def get_raw(self, raw_key: str) -> Optional[IO[bytes]]: # pragma: no cover 149 | now = datetime.utcnow() 150 | with closing(self.conn.cursor()) as cursor: 151 | cursor.execute(TOUCH_DML, (now, raw_key, now)) 152 | if self._has_blobopen: 153 | cursor.execute(GET_DQL_FOR_BLOBOPEN, (raw_key, now)) 154 | else: 155 | cursor.execute(GET_DQL, (raw_key, now)) 156 | v = cursor.fetchone() 157 | if v is not None: 158 | if self._has_blobopen: 159 | rowid = v[0] 160 | blob = self.conn.blobopen("pyappcache", "value", rowid, readonly=True) 161 | # we need readline above in the stack, for pickle. 162 | # frustratingly sqlite3.Blob does not have that and none of the 163 | # wrappers in io seem able to polyfill it 164 | rv = io.BytesIO() 165 | shutil.copyfileobj(blob, rv) 166 | rv.seek(0) 167 | else: 168 | (cache_contents,) = v 169 | rv = io.BytesIO(cache_contents) 170 | else: 171 | rv = None 172 | self.conn.commit() 173 | return rv 174 | 175 | def set_raw( 176 | self, key_bytes: str, value_bytes: IO[bytes], ttl: int 177 | ) -> None: # pragma: no cover 178 | last_read = datetime.utcnow() 179 | expiry: Union[str, datetime] 180 | if ttl != 0: 181 | expiry = last_read + timedelta(seconds=ttl) 182 | else: 183 | expiry = "-1" 184 | with closing(self.conn.cursor()) as cursor: 185 | if self._has_blobopen: 186 | value_bytes.seek(0, io.SEEK_END) 187 | value_length = value_bytes.tell() 188 | value_bytes.seek(0) 189 | cursor.execute( 190 | SET_DML_FOR_BLOBOPEN, (key_bytes, value_length, expiry, last_read) 191 | ) 192 | rowid = cursor.lastrowid 193 | with closing(self.conn.blobopen("pyappcache", "value", rowid)) as blob: 194 | shutil.copyfileobj(value_bytes, blob) 195 | else: 196 | cursor.execute( 197 | SET_DML, (key_bytes, value_bytes.read(), expiry, last_read) 198 | ) 199 | cursor.execute(EVICT_DML, (self.max_size,)) 200 | 201 | self.conn.commit() 202 | 203 | def ttl(self, key_bytes: str) -> Optional[int]: 204 | """Returns the (remaining) TTL of the given key.""" 205 | now = datetime.utcnow() 206 | with closing(self.conn.cursor()) as cursor: 207 | cursor.execute(GET_TTL_DQL, (key_bytes,)) 208 | row = cursor.fetchone() 209 | if row is not None: 210 | expiry = row[0] 211 | expiry_dt = parse_dt(expiry) 212 | ttl_td = expiry_dt - now 213 | return int(ttl_td.total_seconds()) 214 | else: 215 | return None 216 | 217 | def invalidate_raw(self, raw_key: str) -> None: 218 | with closing(self.conn.cursor()) as cursor: 219 | cursor.execute(INVALIDATE_DML, (raw_key,)) 220 | self.conn.commit() 221 | 222 | def clear(self) -> None: 223 | with closing(self.conn.cursor()) as cursor: 224 | cursor.execute(CLEAR_DML) 225 | self.conn.commit() 226 | -------------------------------------------------------------------------------- /pyappcache/util/__init__.py: -------------------------------------------------------------------------------- 1 | # 2 | -------------------------------------------------------------------------------- /pyappcache/util/requests.py: -------------------------------------------------------------------------------- 1 | from typing import Optional 2 | 3 | from ..cache import Cache 4 | from ..keys import SimpleStringKey 5 | 6 | CacheControlKey = SimpleStringKey[bytes] 7 | 8 | 9 | class CacheControlProxy: 10 | """A proxy to allow :class:`~pyappcache.cache.Cache` instances to be 11 | converted for the cachecontrol library's desired API. 12 | 13 | """ 14 | 15 | def __init__(self, cache: Cache): 16 | """ 17 | 18 | :parameter cache: An instances of :class:`~pyappcache.Cache` to proxy.""" 19 | self.cache = cache 20 | 21 | def get(self, key_str: str) -> Optional[bytes]: 22 | key = CacheControlKey(key_str) 23 | return self.cache.get(key) 24 | 25 | def set(self, key_str: str, value: bytes, expires: Optional[int] = None) -> None: 26 | key = CacheControlKey(key_str) 27 | self.cache.set(key, value, ttl_seconds=expires or 0) 28 | 29 | def delete(self, key_str: str) -> None: 30 | key = CacheControlKey(key_str) 31 | self.cache.invalidate(key) 32 | -------------------------------------------------------------------------------- /pytest.ini: -------------------------------------------------------------------------------- 1 | [pytest] 2 | log_level = DEBUG 3 | filterwarnings = 4 | ignore:.*imp.*:DeprecationWarning -------------------------------------------------------------------------------- /setup.py: -------------------------------------------------------------------------------- 1 | from setuptools import setup, find_packages 2 | 3 | VERSION = open("VERSION").read().strip() 4 | README = open("README.rst").read() 5 | 6 | redis_requirements = ["redis>=3"] 7 | memcache_requirements = ["pylibmc"] 8 | test_requirements = [ 9 | "black~=22.10.0", 10 | "cachecontrol", 11 | "flask", 12 | "mypy==0.991", 13 | "pandas", 14 | "pandas-stubs", 15 | "pyarrow", 16 | "pyflakes", 17 | "pytest-cov", 18 | "pytest~=7.2.0", 19 | "requests", 20 | "sphinx-autodoc-typehints~=1.19.5", 21 | "sphinx==5.3.0", 22 | "time-machine~=2.13.0", 23 | "types-python-dateutil", 24 | "types-redis", 25 | "types-requests", 26 | "wheel", 27 | ] 28 | 29 | setup( 30 | name="pyappcache", 31 | version=VERSION, 32 | packages=find_packages(exclude=["tests.*", "tests"]), 33 | package_data={"pyappcache": ["py.typed"]}, 34 | include_package_data=True, 35 | long_description=README, 36 | long_description_content_type="text/markdown", 37 | python_requires=">=3.8", 38 | install_requires=["typing_extensions", "python-dateutil"], 39 | extras_require={ 40 | "redis": redis_requirements, 41 | "memcache": memcache_requirements, 42 | "tests": test_requirements + memcache_requirements + redis_requirements, 43 | "dev": ["bpython~=0.18"], 44 | }, 45 | project_urls={ 46 | "Documentation": "https://pyappcache.readthedocs.io/en/latest/", 47 | "Code": "https://github.com/calpaterson/pyappcache", 48 | "Issue tracker": "https://github.com/calpaterson/pyappcache/issues", 49 | }, 50 | url="https://github.com/calpaterson/pyappcache", 51 | author="Cal Paterson", 52 | author_email="cal@calpaterson.com", 53 | classifiers=[ 54 | "Intended Audience :: Developers", 55 | "License :: OSI Approved :: GNU General Public License v3 (GPLv3)", 56 | "Programming Language :: Python :: 3", 57 | "Programming Language :: Python :: 3.10", 58 | "Programming Language :: Python :: 3.11", 59 | "Programming Language :: Python :: 3.12", 60 | "Programming Language :: Python :: 3.8", 61 | "Programming Language :: Python :: 3.9", 62 | ], 63 | ) 64 | -------------------------------------------------------------------------------- /tests/__init__.py: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/calpaterson/pyappcache/f4bff4f8d522c6103e378be32b97e35bff116f36/tests/__init__.py -------------------------------------------------------------------------------- /tests/conftest.py: -------------------------------------------------------------------------------- 1 | from pathlib import Path 2 | 3 | import redis as redis_py 4 | import pylibmc 5 | 6 | from pyappcache.cache import Cache 7 | from pyappcache.memcache import MemcacheCache 8 | from pyappcache.redis import RedisCache 9 | from pyappcache.sqlite_lru import SqliteCache 10 | from pyappcache.fs import FilesystemCache 11 | 12 | import pytest 13 | from .utils import random_string, StringToStringKey, StringToStringKeyWithCompression 14 | 15 | 16 | @pytest.fixture(scope="session") 17 | def memcache_client(): 18 | return pylibmc.Client(["127.0.0.1"], binary=True) 19 | 20 | 21 | @pytest.fixture(scope="session") 22 | def redis_client(): 23 | return redis_py.Redis() 24 | 25 | 26 | @pytest.fixture(scope="function", params=["redis", "memcache", "sqlite", "fs"]) 27 | def cache(request, redis_client, memcache_client, tmpdir): 28 | """Cache object""" 29 | cache: Cache 30 | if request.param == "redis": 31 | cache = RedisCache(redis_client) 32 | elif request.param == "sqlite": 33 | cache = SqliteCache() 34 | elif request.param == "fs": 35 | cache = FilesystemCache(Path(str(tmpdir))) 36 | else: 37 | cache = MemcacheCache(memcache_client) 38 | 39 | # Randomise the prefix 40 | cache.prefix = random_string() 41 | 42 | return cache 43 | 44 | 45 | @pytest.fixture(params=[StringToStringKey, StringToStringKeyWithCompression]) 46 | def KeyCls(request): 47 | return request.param 48 | 49 | 50 | test_data = Path(__file__).parent.resolve() / "test-data" 51 | -------------------------------------------------------------------------------- /tests/test-data/stock-exchanges.parquet: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/calpaterson/pyappcache/f4bff4f8d522c6103e378be32b97e35bff116f36/tests/test-data/stock-exchanges.parquet -------------------------------------------------------------------------------- /tests/test_caches.py: -------------------------------------------------------------------------------- 1 | from io import BytesIO 2 | 3 | from pyappcache.cache import Cache 4 | from pyappcache.keys import build_raw_key 5 | from pyappcache.memcache import MemcacheCache 6 | from pyappcache.sqlite_lru import SqliteCache 7 | from pyappcache.redis import RedisCache 8 | from pyappcache.fs import FilesystemCache 9 | 10 | import pytest 11 | from .utils import random_string, StringToStringKeyWithCompression, random_bytes 12 | 13 | 14 | def test_get_and_set_no_ttl(cache, KeyCls): 15 | v = "a" 16 | key = KeyCls(random_string()) 17 | cache.set(key, v) 18 | got = cache.get(key) 19 | assert got == v 20 | 21 | 22 | def test_ttl_when_key_not_set(cache): 23 | if not hasattr(cache, "ttl"): 24 | pytest.skip("ttl is not implemented") 25 | key = random_string().encode("utf-8") 26 | assert cache.ttl(key) is None 27 | 28 | 29 | def test_get_and_set_10k_sec_ttl(cache, KeyCls): 30 | key = KeyCls(random_string()) 31 | cache.set(key, "a", ttl_seconds=10_000) 32 | 33 | key_str = build_raw_key(cache.prefix, key) 34 | if isinstance(cache, MemcacheCache): 35 | # Is there any way to do this? 36 | pytest.skip("memcache ttl checker is too flaky") 37 | # ttl = get_memcache_ttl(key_str) 38 | elif isinstance(cache, SqliteCache): 39 | ttl = cache.ttl(key_str) 40 | elif isinstance(cache, FilesystemCache): 41 | ttl = cache.ttl(key_str) 42 | elif isinstance(cache, RedisCache): 43 | ttl = cache._redis.ttl(key_str) 44 | assert cache.get(key) == "a" 45 | assert ttl is not None 46 | assert ttl > 9_000 47 | 48 | 49 | def test_overwrite(cache, KeyCls): 50 | key = KeyCls(random_string()) 51 | cache.set(key, "a") 52 | cache.set(key, "b") 53 | assert cache.get(key) == "b" 54 | 55 | 56 | def test_get_and_set_absent(cache, KeyCls): 57 | key = KeyCls(random_string()) 58 | assert cache.get(key) is None 59 | 60 | 61 | def test_invalidate(cache, KeyCls): 62 | key = KeyCls(random_string()) 63 | cache.set(key, "a") 64 | cache.invalidate(key) 65 | assert cache.get(key) is None 66 | 67 | 68 | def test_clear(cache, KeyCls): 69 | key = KeyCls(random_string()) 70 | cache.set(key, "a") 71 | cache.clear() 72 | assert cache.get(key) is None 73 | 74 | 75 | def test_unreadable_pickle(cache, KeyCls): 76 | key = KeyCls(random_string()) 77 | key_segments = [cache.prefix] 78 | key_segments.extend(key.cache_key_segments()) 79 | key_bytes = "/".join(key_segments) 80 | cache.set_raw(key_bytes, BytesIO(b"good luck unpickling this"), 0) 81 | 82 | assert cache.get(key) is None 83 | 84 | 85 | def test_prefixing(cache, KeyCls): 86 | key = KeyCls(random_string()) 87 | cache.set(key, "a") 88 | cache.prefix = random_string() 89 | assert cache.get(key) is None 90 | 91 | 92 | def test_by_str(cache, KeyCls): 93 | key_subj = random_string() 94 | key = KeyCls(key_subj) 95 | str_key = key_subj 96 | 97 | cache.set(key, "a") 98 | assert cache.get_by_str(str_key) == "a" 99 | 100 | cache.invalidate_by_str(str_key) 101 | assert cache.get_by_str(key) is None 102 | 103 | cache.set_by_str(str_key, "b") 104 | assert cache.get(key) == "b" 105 | 106 | cache.invalidate_by_str(str_key) 107 | assert cache.get(key) is None 108 | 109 | 110 | def test_compression_via_key(cache): 111 | key = StringToStringKeyWithCompression(random_string()) 112 | cache.set(key, "b") 113 | 114 | raw_value = cache.get_raw(build_raw_key(cache.prefix, key)).read() 115 | assert raw_value.startswith(b"\x1f\x8b") 116 | 117 | 118 | def test_compression_via_str(cache): 119 | cache.set_by_str("a", "b", compress=True) 120 | raw_value = cache.get_raw(build_raw_key(cache.prefix, "a")).read() 121 | assert raw_value.startswith(b"\x1f\x8b") 122 | 123 | 124 | def test_get_via(cache, KeyCls): 125 | key = KeyCls(random_string()) 126 | 127 | getter_called = False 128 | 129 | def fake_getter(): 130 | nonlocal getter_called 131 | getter_called = True 132 | return "ok" 133 | 134 | cache.get_via(key, fake_getter) 135 | assert getter_called is True 136 | 137 | getter_called = False 138 | cache.get_via(key, fake_getter) 139 | assert getter_called is False 140 | 141 | 142 | def test_set_via(cache, KeyCls): 143 | key = KeyCls(random_string()) 144 | 145 | db = {} 146 | 147 | def fake_setter(id_, value): 148 | db[id_] = value 149 | 150 | value = random_string() 151 | cache.set_via(key, value, fake_setter, setter_args=("a", value)) 152 | 153 | assert cache.get(key) == value 154 | assert db["a"] == value 155 | 156 | 157 | def test_set_via_setter_fails(cache, KeyCls): 158 | key = KeyCls(random_string()) 159 | 160 | def fake_setter(id_, value): 161 | raise RuntimeError("bad bytes!") 162 | 163 | value = random_string() 164 | with pytest.raises(RuntimeError): 165 | cache.set_via(key, value, fake_setter, setter_args=("a", value)) 166 | 167 | assert cache.get(key) is None 168 | 169 | 170 | def test_default_prefix(cache): 171 | cache.prefix = Cache.DEFAULT_PREFIX 172 | key = random_string() 173 | value = random_string() 174 | cache.set_by_str(key, value) 175 | 176 | assert cache.get_raw("/".join(["pyappcache", key])) is not None 177 | 178 | 179 | def test_eviction__max_size_is_maintained(cache): 180 | """Test that eviction happens on set_raw.""" 181 | if not hasattr(cache, "max_size_bytes"): 182 | pytest.skip(reason="cache doesn't have a max_size_bytes param") 183 | 184 | cache.max_size_bytes = 100 185 | 186 | a_val = random_bytes(49) 187 | b_val = random_bytes(49) 188 | c_val = random_bytes(49) 189 | 190 | cache.set_raw("a", BytesIO(a_val), 100) 191 | cache.set_raw("b", BytesIO(b_val), 100) 192 | cache.set_raw("c", BytesIO(c_val), 100) 193 | 194 | assert cache.get_raw("a") is None 195 | assert cache.get_raw("b").read() == b_val 196 | assert cache.get_raw("c").read() == c_val 197 | 198 | 199 | def test_eviction__reading_is_a_touch(cache): 200 | if not hasattr(cache, "max_size_bytes"): 201 | pytest.skip(reason="cache doesn't have a max_size_bytes param") 202 | 203 | cache.max_size_bytes = 100 204 | 205 | a_val = random_bytes(49) 206 | b_val = random_bytes(49) 207 | c_val = random_bytes(49) 208 | 209 | cache.set_raw("a", BytesIO(a_val), 100) 210 | cache.set_raw("b", BytesIO(b_val), 100) 211 | cache.get_raw("a") 212 | cache.set_raw("c", BytesIO(c_val), 100) 213 | 214 | assert cache.get_raw("a").read() == a_val 215 | assert cache.get_raw("b") is None 216 | assert cache.get_raw("c").read() == c_val 217 | -------------------------------------------------------------------------------- /tests/test_compression.py: -------------------------------------------------------------------------------- 1 | from io import BytesIO 2 | 3 | from pyappcache.compression import GZIPCompressor 4 | 5 | import pytest 6 | 7 | 8 | @pytest.fixture(scope="session") 9 | def compressor(): 10 | return GZIPCompressor() 11 | 12 | 13 | def test_compress_and_decompress(compressor): 14 | buf = BytesIO(b"hello, world") 15 | decompressed = compressor.decompress(compressor.compress(buf)).read() 16 | buf.seek(0) 17 | expected = buf.read() 18 | assert expected == decompressed 19 | -------------------------------------------------------------------------------- /tests/test_keys.py: -------------------------------------------------------------------------------- 1 | from pyappcache.serialisation import PickleSerialiser 2 | from pyappcache.keys import SimpleStringKey, Key 3 | from .utils import StringToIntKey 4 | 5 | 6 | def test_simple_key_to_segments(): 7 | key = StringToIntKey("freddie") 8 | assert key.cache_key_segments() == ["freddie"] 9 | 10 | 11 | def test_should_compress(): 12 | key = StringToIntKey("freddie") 13 | obj = 1 14 | as_bytes = PickleSerialiser().dump(obj) 15 | assert key.should_compress(obj, as_bytes) is False 16 | 17 | 18 | def test_simple_string_key_repr(): 19 | key: Key[str] = SimpleStringKey("foo") 20 | assert repr(key) == "" 21 | -------------------------------------------------------------------------------- /tests/test_memcache.py: -------------------------------------------------------------------------------- 1 | import pickle 2 | import pylibmc 3 | 4 | import pytest 5 | 6 | from pyappcache.memcache import MemcacheCache 7 | from .utils import random_string 8 | 9 | 10 | class FlakeyClient: 11 | def __init__(self, flakes): 12 | self.count = 0 13 | self.flakes = flakes 14 | 15 | def get(self, key): 16 | if self.count >= self.flakes: 17 | return pickle.dumps("good bytes") 18 | else: 19 | self.count += 1 20 | raise pylibmc.ConnectionError("nope") 21 | 22 | def set(self, key, value, time): 23 | if self.count >= self.flakes: 24 | return None 25 | else: 26 | self.count += 1 27 | raise pylibmc.ConnectionError("nope") 28 | 29 | def delete(self, key): 30 | if self.count >= self.flakes: 31 | return None 32 | else: 33 | self.count += 1 34 | raise pylibmc.ConnectionError("nope") 35 | 36 | def flush_all(self): 37 | if self.count >= self.flakes: 38 | return None 39 | else: 40 | self.count += 1 41 | raise pylibmc.ConnectionError("nope") 42 | 43 | 44 | @pytest.mark.parametrize( 45 | "method_name, args, expected", 46 | [ 47 | ("get_by_str", ("a",), "good bytes"), 48 | ("set_by_str", ("a", "b"), None), 49 | ("invalidate_by_str", ("a"), None), 50 | ("clear", (), None), 51 | ], 52 | ) 53 | def test_retry_on_disconnect(method_name, args, expected): 54 | """Check we try to reconnect (exactly once) to the memcache server if we get disconnected.""" 55 | 56 | cache = MemcacheCache(FlakeyClient(1)) 57 | assert getattr(cache, method_name)(*args) == expected 58 | 59 | 60 | def test_retry_gives_up_on_down(): 61 | """Check we don't retry forever""" 62 | 63 | cache = MemcacheCache(FlakeyClient(2)) 64 | with pytest.raises(pylibmc.ConnectionError): 65 | cache.get_by_str("foo") 66 | 67 | 68 | def test_default_client(): 69 | cache = MemcacheCache() 70 | cache.get_by_str(random_string()) is None 71 | -------------------------------------------------------------------------------- /tests/test_namespacing.py: -------------------------------------------------------------------------------- 1 | from datetime import datetime 2 | import logging 3 | 4 | from pyappcache.keys import BaseKey 5 | 6 | 7 | class UserToLastChangedKey(BaseKey[datetime]): 8 | def __init__(self, username: str): 9 | self._username = username 10 | 11 | def cache_key_segments(self): 12 | return [self._username, "last_changed"] 13 | 14 | 15 | class UserFavouritePokemon(BaseKey[str]): 16 | def __init__(self, username: str): 17 | self._username = username 18 | 19 | def namespace_key(self): 20 | return UserToLastChangedKey(self._username) 21 | 22 | def cache_key_segments(self): 23 | return ["favourite_pokemon"] 24 | 25 | 26 | def test_namespace_get_when_no_namespace(cache): 27 | key = UserFavouritePokemon("john") 28 | 29 | cache.set(key.namespace_key(), datetime(2018, 1, 3)) 30 | cache.set(key, "pikachu") 31 | cache.invalidate(key.namespace_key()) 32 | assert cache.get(key) is None 33 | 34 | 35 | def test_namespace_set_when_no_namespace(cache): 36 | key = UserFavouritePokemon("john") 37 | 38 | cache.set(key, "pikachu") 39 | assert cache.get(key) is None 40 | 41 | 42 | def test_namespace_get_and_set_when_namespace_present(cache): 43 | key = UserFavouritePokemon("john") 44 | 45 | cache.set(key.namespace_key(), datetime(2018, 1, 3)) 46 | cache.set(key, "pikachu") 47 | 48 | assert cache.get(key) == "pikachu" 49 | 50 | 51 | def test_get_and_set_when_namespace_outdated(cache): 52 | key = UserFavouritePokemon("john") 53 | 54 | cache.set(key.namespace_key(), datetime(2018, 1, 3)) 55 | cache.set(key, "pikachu") 56 | cache.set(key.namespace_key(), datetime(2018, 1, 4)) 57 | 58 | assert cache.get(key) is None 59 | 60 | 61 | def test_get_and_set_when_namespace_updated(cache): 62 | key = UserFavouritePokemon("john") 63 | 64 | cache.set(key.namespace_key(), datetime(2018, 1, 3)) 65 | cache.set(key, "pikachu") 66 | cache.set(key.namespace_key(), datetime(2018, 1, 4)) 67 | cache.set(key, "bulbasaur") 68 | 69 | assert cache.get(key) == "bulbasaur" 70 | 71 | 72 | def test_invalidation_when_no_namespace(cache, caplog): 73 | key = UserFavouritePokemon("john") 74 | 75 | with caplog.at_level(logging.WARNING, logger="pyappcache.cache"): 76 | cache.invalidate(key) 77 | assert caplog.record_tuples == [ 78 | ( 79 | "pyappcache.cache", 80 | 30, 81 | "unable to invalidate key as namespace does not exist", 82 | ) 83 | ] 84 | 85 | 86 | def test_invalidation_when_namespace_present(cache): 87 | key = UserFavouritePokemon("john") 88 | 89 | cache.set(key.namespace_key(), datetime(2018, 1, 3)) 90 | cache.set(key, "pikachu") 91 | 92 | cache.invalidate(key) 93 | assert cache.get(key) is None 94 | -------------------------------------------------------------------------------- /tests/test_redis.py: -------------------------------------------------------------------------------- 1 | from pyappcache.redis import RedisCache 2 | from .utils import random_string 3 | 4 | 5 | def test_default_client(): 6 | cache = RedisCache() 7 | cache.get_by_str(random_string()) is None 8 | -------------------------------------------------------------------------------- /tests/test_requests.py: -------------------------------------------------------------------------------- 1 | import threading 2 | from datetime import datetime, timedelta 3 | from contextlib import closing 4 | import socket 5 | import time 6 | 7 | import requests 8 | import cachecontrol 9 | import flask 10 | 11 | import requests.models 12 | import requests.adapters 13 | import pytest 14 | 15 | from pyappcache.util.requests import CacheControlProxy 16 | 17 | 18 | def get_free_port(): 19 | with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as s: 20 | s.bind(("", 0)) 21 | s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) 22 | return s.getsockname()[1] 23 | 24 | 25 | @pytest.fixture(scope="session") 26 | def local_server(): 27 | app = flask.Flask("local-server") 28 | app.config["calls"] = 0 29 | 30 | @app.route("/", methods=["GET"]) 31 | def get_route(): 32 | response = flask.make_response(b"hello") 33 | response.headers["Cache-Control"] = "max-age=200" 34 | app.config["calls"] += 1 35 | return response 36 | 37 | @app.route("/ok", methods=["GET"]) 38 | def ok(): 39 | return "ok" 40 | 41 | @app.route("/", methods=["DELETE"]) 42 | def delete_route(): 43 | response = flask.make_response(b"goodbye") 44 | app.config["calls"] += 1 45 | return response 46 | 47 | port = get_free_port() 48 | 49 | thread = threading.Thread( 50 | target=app.run, kwargs={"port": port, "debug": False}, daemon=True 51 | ) 52 | thread.start() 53 | 54 | # Wait until the server has started up (check by polling) 55 | give_up_time = datetime.utcnow() + timedelta(seconds=5) 56 | sesh = requests.Session() 57 | while give_up_time > datetime.utcnow(): 58 | try: 59 | sesh.get(f"http://localhost:{port}/ok", timeout=0.001) 60 | break 61 | except requests.exceptions.RequestException: 62 | pass 63 | time.sleep(0) # aka thread.yield 64 | 65 | return app, port 66 | 67 | 68 | def test_request_with_cache_control(cache, local_server): 69 | """Check that requests are cached properly""" 70 | app, port = local_server 71 | initial_calls = app.config["calls"] 72 | 73 | url = f"http://localhost:{port}/" 74 | 75 | proxy = CacheControlProxy(cache) 76 | 77 | sesh = requests.Session() 78 | cached_sesh = cachecontrol.CacheControl(sesh, cache=proxy) # type: ignore 79 | 80 | response1 = cached_sesh.get(url) 81 | assert response1.status_code == 200 82 | assert response1.content == b"hello" 83 | 84 | response2 = cached_sesh.get(url) 85 | assert response2.status_code == 200 86 | assert response2.content == b"hello" 87 | 88 | assert app.config["calls"] == (initial_calls + 1) 89 | 90 | 91 | def test_deletion_with_cache_control(cache, local_server): 92 | """Check that issuing a delete clears the entry from the cache""" 93 | app, port = local_server 94 | 95 | url = f"http://localhost:{port}/" 96 | 97 | proxy = CacheControlProxy(cache) 98 | 99 | sesh = requests.Session() 100 | cached_sesh = cachecontrol.CacheControl(sesh, cache=proxy) # type: ignore 101 | 102 | response1 = cached_sesh.get(url) 103 | assert response1.status_code == 200 104 | assert response1.content == b"hello" 105 | 106 | response2 = cached_sesh.delete(url) 107 | assert response2.status_code == 200 108 | assert response2.content == b"goodbye" 109 | 110 | assert proxy.get(url) is None 111 | -------------------------------------------------------------------------------- /tests/test_serialisation.py: -------------------------------------------------------------------------------- 1 | from io import BytesIO, StringIO 2 | 3 | import pandas as pd 4 | from pandas.testing import assert_frame_equal 5 | import pytest 6 | 7 | from .conftest import test_data 8 | 9 | from pyappcache.serialisation import PickleSerialiser, BinaryFileSerialiser 10 | from pyappcache.serialisation.pandas import DataFrameAwareSerialiser 11 | 12 | stock_exchanges = pd.read_parquet(test_data / "stock-exchanges.parquet") 13 | 14 | 15 | def test_pickle_serialiser(): 16 | serialiser = PickleSerialiser() 17 | loaded = serialiser.load(serialiser.dump(BytesIO(b"a"))).read() 18 | assert loaded == b"a" 19 | 20 | 21 | def test_dataframe_serialiser__doesnt_change_df(): 22 | serialiser = DataFrameAwareSerialiser() 23 | loaded = serialiser.load(serialiser.dump(stock_exchanges)) 24 | assert_frame_equal(loaded, stock_exchanges) 25 | 26 | 27 | def test_dataframe_serialiser__handles_junk(): 28 | serialiser = DataFrameAwareSerialiser() 29 | assert serialiser.load(BytesIO(b"junk")) is None 30 | 31 | 32 | def test_dataframe_serialised__handles_normal_objects(): 33 | serialiser = DataFrameAwareSerialiser() 34 | loaded = serialiser.load(serialiser.dump(BytesIO(b"a"))).read() 35 | assert loaded == b"a" 36 | 37 | 38 | def test_binary_file_serialiser__works_on_files(): 39 | serialiser = BinaryFileSerialiser() 40 | buf = BytesIO(b"hello") 41 | assert serialiser.dump(buf).getvalue() == b"hello" 42 | 43 | assert serialiser.load(buf).getvalue() == b"hello" 44 | 45 | 46 | def test_binary_file_serialiser__explodes_on_objects(): 47 | serialiser = BinaryFileSerialiser() 48 | with pytest.raises(RuntimeError): 49 | serialiser.dump({}) 50 | 51 | 52 | def test_binary_file_serialiser__explodes_on_text_file(): 53 | serialiser = BinaryFileSerialiser() 54 | buf = StringIO("hello") 55 | with pytest.raises(RuntimeError): 56 | serialiser.dump(buf) 57 | -------------------------------------------------------------------------------- /tests/test_sqlite_lru.py: -------------------------------------------------------------------------------- 1 | from datetime import datetime 2 | import contextlib 3 | import sqlite3 4 | 5 | import pytest 6 | import time_machine 7 | from pyappcache.sqlite_lru import SqliteCache 8 | from .utils import StringToStringKey, random_string 9 | 10 | 11 | @pytest.fixture(scope="function") 12 | def random_conn(): 13 | """A random sqlite3 conn, to prevent clashes between tests""" 14 | return sqlite3.connect(f"file:{random_string()}?mode=memory&cache=shared") 15 | 16 | 17 | def test_sqlite3_lru(random_conn): 18 | """Test that the LRU functionality for SQLite3Cache works right by causing 19 | an eviction.""" 20 | cache = SqliteCache(max_size=5, connection=random_conn) 21 | 22 | for i in range(6): 23 | cache.set(StringToStringKey(str(i)), "something") 24 | 25 | assert cache.get(StringToStringKey("0")) is None 26 | 27 | 28 | def test_sqlite_lru_with_backing_file(tmp_path): 29 | """Test that it works with a backing file (as opposed to the default, in 30 | memory option)""" 31 | path = tmp_path / "cache.sqlite3" 32 | 33 | with contextlib.closing(sqlite3.connect(str(path))) as connection: 34 | cache = SqliteCache(max_size=5, connection=connection) 35 | 36 | cache.set(StringToStringKey("a"), "b") 37 | 38 | assert path.exists() 39 | 40 | 41 | def test_in_memory_db_naming(): 42 | """Test that our in memory sqlite db does not clash with ordinary 43 | ':memory:' sqlite databases.""" 44 | cache = SqliteCache() 45 | 46 | cache.set(StringToStringKey("a"), "b") 47 | 48 | table_dql = """ 49 | SELECT name FROM sqlite_master WHERE type = 'table'; 50 | """ 51 | in_memory_conn = sqlite3.connect(":memory:") 52 | tables = in_memory_conn.execute(table_dql).fetchall() 53 | 54 | assert len(tables) == 0 55 | 56 | 57 | def test_sqlite3_ttls_cause_expiry(random_conn): 58 | """Test that TTLs do cause keys to expire""" 59 | cache = SqliteCache(connection=random_conn) 60 | 61 | key = StringToStringKey("a") 62 | with time_machine.travel(datetime(2018, 1, 3)): 63 | cache.set(key, "b", ttl_seconds=1) 64 | 65 | with time_machine.travel(datetime(2018, 1, 4)): 66 | assert cache.get(key) is None 67 | 68 | 69 | def test_sqlite3_no_ttls_never_expire(random_conn): 70 | """Test that keys set with a 0 ttl never expire""" 71 | cache = SqliteCache(connection=random_conn) 72 | 73 | key = StringToStringKey("a") 74 | with time_machine.travel(datetime(2018, 1, 3)): 75 | cache.set(key, "1") 76 | 77 | with time_machine.travel(datetime(2019, 1, 3)): 78 | assert cache.get(key) == "1" 79 | 80 | 81 | def test_sqlite3_eviction_with_ttls(random_conn): 82 | """Test that evictions happen in order of last_read, not ttl""" 83 | cache = SqliteCache(max_size=1, connection=random_conn) 84 | 85 | key_a = StringToStringKey("a") 86 | with time_machine.travel(datetime(2018, 1, 3, 0)): 87 | cache.set(key_a, "1", ttl_seconds=36000) 88 | 89 | key_b = StringToStringKey("b") 90 | with time_machine.travel(datetime(2018, 1, 3, 1)): 91 | cache.set(key_b, "2", ttl_seconds=10) 92 | 93 | assert cache.get(key_a) is None 94 | assert cache.get(key_b) == "2" 95 | 96 | 97 | def test_sqlite3_eviction_without_ttls(random_conn): 98 | cache = SqliteCache(max_size=1, connection=random_conn) 99 | 100 | key_a = StringToStringKey("a") 101 | with time_machine.travel(datetime(2018, 1, 3, 0)): 102 | cache.set(key_a, "1") 103 | 104 | key_b = StringToStringKey("b") 105 | with time_machine.travel(datetime(2018, 1, 3, 1)): 106 | cache.set(key_b, "2") 107 | 108 | assert cache.get(key_a) is None 109 | assert cache.get(key_b) == "2" 110 | 111 | 112 | def test_sqlite3_eviction_via_last_read(random_conn): 113 | cache = SqliteCache(max_size=2, connection=random_conn) 114 | 115 | with time_machine.travel(datetime(2018, 1, 3, 0)): 116 | key_a = StringToStringKey("a") 117 | cache.set(key_a, "1", ttl_seconds=36000) 118 | 119 | with time_machine.travel(datetime(2018, 1, 3, 1)): 120 | key_b = StringToStringKey("b") 121 | cache.set(key_b, "2", ttl_seconds=36000) 122 | 123 | with time_machine.travel(datetime(2018, 1, 3, 2)): 124 | cache.get(key_a) 125 | 126 | with time_machine.travel(datetime(2018, 1, 3, 3)): 127 | key_c = StringToStringKey("c") 128 | cache.set(key_c, "3", ttl_seconds=36000) 129 | 130 | assert cache.get(key_b) is None 131 | assert cache.get(key_a) == "1" 132 | -------------------------------------------------------------------------------- /tests/utils.py: -------------------------------------------------------------------------------- 1 | from typing import Optional 2 | import re 3 | import random 4 | import string 5 | import socket 6 | from datetime import datetime, timedelta 7 | from logging import getLogger 8 | 9 | from pyappcache.keys import SimpleStringKey 10 | 11 | logger = getLogger(__name__) 12 | 13 | StringToIntKey = SimpleStringKey[int] 14 | StringToStringKey = SimpleStringKey[str] 15 | 16 | 17 | class StringToStringKeyWithCompression(StringToStringKey): 18 | def should_compress(self, python_obj, as_bytes): 19 | return True 20 | 21 | 22 | def random_string(n: int = 32) -> str: 23 | return "".join(random.choice(string.ascii_lowercase) for _ in range(n)) 24 | 25 | 26 | def random_bytes(n) -> bytes: 27 | return bytes(random_string(n), "utf-8") 28 | 29 | 30 | ONE_MEG = 1024 * 1024 * 1024 31 | 32 | SLAB_REGEX = re.compile(rb":(\d+):") 33 | 34 | 35 | def get_memcache_ttl(key: str) -> Optional[int]: 36 | """There is no way to get the ttl of a key from pylibmc so we do it out of 37 | band with a socket via the text API.""" 38 | logger.info("looking up the ttl of: %s", key) 39 | timelimit = datetime.utcnow() + timedelta(seconds=1) 40 | ttl_regex = re.compile( 41 | rb"ITEM %s \[[0-9]+ b; ([0-9]+) s]" % bytes(key, "utf-8"), re.MULTILINE 42 | ) 43 | 44 | attempt = 1 45 | # Looks like something is causing the IO to happen async so try for a second 46 | sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 47 | sock.connect(("localhost", 11211)) 48 | while datetime.utcnow() < timelimit: 49 | # 1. Get a list of slabs 50 | sock.send(b"stats items\r\n") 51 | response = sock.recv(ONE_MEG) 52 | logger.debug("memcached stats items response: \n%s", response) 53 | slabs = set(int(slab) for slab in SLAB_REGEX.findall(response)) 54 | 55 | # 2. Check every slab for our item 56 | for slab in slabs: 57 | command = bytes(f"stats cachedump {slab} 10\r\n", "utf-8") 58 | sock.send(command) 59 | response = sock.recv(ONE_MEG) 60 | logger.debug("memcached stats cachedump response: \n%s", response) 61 | match_obj = ttl_regex.search(response) 62 | if match_obj: 63 | ttl = int(match_obj.group(1)) 64 | logger.info("found ttl for %s: %d (on attempt %d)", key, ttl, attempt) 65 | return ttl 66 | attempt += 1 67 | return None 68 | -------------------------------------------------------------------------------- /tox.ini: -------------------------------------------------------------------------------- 1 | [tox] 2 | skipsdist = True 3 | envlist = py38, py39, py310, py311, 312 4 | 5 | [gh-actions] 6 | python = 7 | 3.8: py38 8 | 3.9: py39 9 | 3.10: py310 10 | 3.11: py311 11 | 3.11: py311 12 | 3.12: py312 13 | 14 | [testenv] 15 | commands = 16 | pip install --upgrade setuptools pip wheel 17 | pip install -e .[tests] 18 | mypy . 19 | pytest --cov=pyappcache --cov-fail-under 100 20 | black --check . 21 | pyflakes pyappcache 22 | # FIXME: Add -W -n --keep-going 23 | sphinx-build -M html docs build 24 | python setup.py bdist_wheel 25 | [flake8] 26 | max-line-length = 88 --------------------------------------------------------------------------------