├── webcollector
├── plugin
│ ├── __init__.py
│ ├── net.py
│ ├── ram.py
│ └── redis.py
├── config.py
├── net.py
├── __init__.py
├── filter.py
├── db_manager.py
├── generate.py
├── utils.py
├── fetch.py
├── crawler.py
└── model.py
├── .gitignore
├── examples
├── demo_server.py
├── demo_speed.py
├── demo_manual_news_crawler.py
├── demo_auto_news_crawler.py
├── demo_redis_crawler.py
├── demo_detected_filter.py
└── demo_custom_http_request.py
├── setup.py
├── test.py
├── README.md
└── LICENSE
/webcollector/plugin/__init__.py:
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1 |
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/.gitignore:
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1 | /.idea/
2 | **/__pycache__/
3 | /webcollector.egg-info/
4 | /dist/
5 | **/*.p
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/webcollector/config.py:
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1 | # coding=utf-8
2 | DEFAULT_USER_AGENT = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36"
3 |
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/examples/demo_server.py:
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1 | # coding=utf-8
2 | from flask import Flask
3 | import time
4 | import random
5 | app = Flask(__name__)
6 |
7 | @app.route("/")
8 | def index():
9 | time.sleep(2)
10 | return "ok"
11 |
12 | app.run()
13 |
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/webcollector/net.py:
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1 | # coding=utf-8
2 |
3 |
4 | class Requester(object):
5 |
6 | def __enter__(self):
7 | return self
8 |
9 | def __exit__(self, exc_type, exc_val, exc_tb):
10 | pass
11 |
12 | def get_response(self, crawl_datum):
13 | raise NotImplementedError()
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/webcollector/__init__.py:
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1 | # coding=utf-8
2 | import logging
3 | import sys
4 |
5 | from webcollector.plugin.redis import RedisCrawler
6 | from webcollector.plugin.ram import RamCrawler
7 |
8 |
9 | logging.basicConfig(
10 | stream=sys.stdout,
11 | level=logging.INFO,
12 | format='%(asctime)s %(levelname)s: %(message)s')
13 |
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/webcollector/filter.py:
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1 | # coding=utf-8
2 | class Filter(object):
3 | def filter(self, crawl_datum):
4 | return None
5 |
6 |
7 | class HistoryFilter(Filter):
8 | def __init__(self, history):
9 | self.history = history
10 |
11 | def filter(self, crawl_datum):
12 | if crawl_datum.key in self.history:
13 | return crawl_datum
14 | else:
15 | return None
16 |
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/webcollector/db_manager.py:
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1 | # coding=utf-8
2 |
3 |
4 | class DBManager(object):
5 |
6 | def inject(self, seeds, forced=False):
7 | pass
8 |
9 | def init_fetch_and_detect(self):
10 | pass
11 |
12 | def write_fetch(self, crawl_datum):
13 | pass
14 |
15 | def write_detect(self, crawl_datum):
16 | pass
17 |
18 | def merge(self):
19 | pass
20 |
21 | def create_generator(self):
22 | return None
23 |
24 | def clear(self):
25 | pass
26 |
27 | def open(self):
28 | pass
29 |
30 | def close(self):
31 | pass
32 |
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/examples/demo_speed.py:
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1 | # coding=utf-8
2 | import webcollector as wc
3 | import time
4 |
5 |
6 | class RubyChinaCrawler(wc.RamCrawler):
7 | def __init__(self):
8 | super().__init__(auto_detect=False)
9 | self.num_threads = 10
10 | self.add_seeds(["https://ruby-china.org/topics?page={}".format(i) for i in range(1, 40)])
11 |
12 | def visit(self, page, detected):
13 | print("start_visit", page.url)
14 | # time.sleep(4)
15 | print("end_visit", page.url)
16 |
17 |
18 | crawler = RubyChinaCrawler()
19 | start = time.time()
20 | crawler.start(10)
21 | print(time.time() - start)
22 |
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/setup.py:
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1 | from setuptools import setup, find_packages
2 |
3 | setup(
4 | name="webcollector",
5 | version="0.0.5-alpha",
6 | author="Jun Hu",
7 | packages=find_packages(
8 | exclude=[
9 | 'examples'
10 | ]
11 | ),
12 | install_requires=[
13 | "html5lib",
14 | "aiohttp",
15 | "BeautifulSoup4",
16 | "redis",
17 | "requests"
18 | ],
19 | description="WebCollector-Python is an open source web crawler framework based on Python.It provides some simple interfaces for crawling the Web,you can setup a multi-threaded web crawler in less than 5 minutes.",
20 | license="GNU General Public License v3.0 (See LICENSE)",
21 | url="https://github.com/CrawlScript/WebCollector-Python"
22 | )
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/examples/demo_manual_news_crawler.py:
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1 | # coding=utf-8
2 | import webcollector as wc
3 |
4 |
5 | class NewsCrawler(wc.RamCrawler):
6 | def __init__(self):
7 | super().__init__(auto_detect=False)
8 | self.num_threads = 10
9 | self.add_seed("https://github.blog/")
10 |
11 | def visit(self, page, detected):
12 |
13 | detected.extend(page.links("https://github.blog/[0-9]+.*"))
14 |
15 | if page.match_url("https://github.blog/[0-9]+.*"):
16 | title = page.select("h1.lh-condensed")[0].text.strip()
17 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
18 | print("\nURL: ", page.url)
19 | print("TITLE: ", title)
20 | print("CONTENT: ", content[:50], "...")
21 |
22 |
23 | crawler = NewsCrawler()
24 | crawler.start(10)
25 |
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/examples/demo_auto_news_crawler.py:
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1 | # coding=utf-8
2 | import webcollector as wc
3 |
4 |
5 | class NewsCrawler(wc.RamCrawler):
6 | def __init__(self):
7 | super().__init__(auto_detect=True)
8 | self.num_threads = 10
9 | self.add_seed("https://github.blog/")
10 | self.add_regex("+https://github.blog/[0-9]+.*")
11 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
12 |
13 | def visit(self, page, detected):
14 | if page.match_url("https://github.blog/[0-9]+.*"):
15 | title = page.select("h1.lh-condensed")[0].text.strip()
16 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
17 | print("\nURL: ", page.url)
18 | print("TITLE: ", title)
19 | print("CONTENT: ", content[:50], "...")
20 |
21 |
22 | crawler = NewsCrawler()
23 | crawler.start(10)
24 |
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/examples/demo_redis_crawler.py:
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1 | # coding=utf-8
2 | from redis import StrictRedis
3 | import webcollector as wc
4 |
5 |
6 | class NewsCrawler(wc.RedisCrawler):
7 |
8 | def __init__(self):
9 | super().__init__(redis_client=StrictRedis("127.0.0.1"),
10 | db_prefix="news",
11 | auto_detect=True)
12 | self.num_threads = 10
13 | self.resumable = True # you can resume crawling after shutdown
14 | self.add_seed("https://github.blog/")
15 | self.add_regex("+https://github.blog/[0-9]+.*")
16 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
17 |
18 | def visit(self, page, detected):
19 | if page.match_url("https://github.blog/[0-9]+.*"):
20 | title = page.select("h1.lh-condensed")[0].text.strip()
21 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
22 | print("\nURL: ", page.url)
23 | print("TITLE: ", title)
24 | print("CONTENT: ", content[:50], "...")
25 |
26 |
27 | crawler = NewsCrawler()
28 | crawler.start(10)
29 |
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/webcollector/generate.py:
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1 | # coding=utf-8
2 | from webcollector.model import CrawlDatum
3 | from webcollector.filter import Filter
4 |
5 |
6 | class Generator(object):
7 |
8 | def __init__(self):
9 | self.num_generated = 0
10 | self.generator_filter = None
11 |
12 | def next(self):
13 | while True:
14 | crawl_datum = self._next()
15 | if crawl_datum is None:
16 | return crawl_datum
17 | else:
18 | if self.generator_filter is None:
19 | return crawl_datum
20 | else:
21 | crawl_datum = self.generator_filter.filter(crawl_datum)
22 | if crawl_datum is None:
23 | continue
24 | else:
25 | self.num_generated += 1
26 | return crawl_datum
27 |
28 | def _next(self):
29 | return None
30 |
31 |
32 | class StatusGeneratorFilter(Filter):
33 | def filter(self, crawl_datum):
34 | if crawl_datum.status != CrawlDatum.STATUS_DB_SUCCESS:
35 | return crawl_datum
36 | else:
37 | return None
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/examples/demo_detected_filter.py:
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1 | # coding=utf-8
2 | import webcollector as wc
3 | from webcollector.filter import Filter
4 | import re
5 |
6 |
7 | class RegexDetectedFilter(Filter):
8 | def filter(self, crawl_datum):
9 | if re.fullmatch("https://github.blog/2019-02.*", crawl_datum.url):
10 | return crawl_datum
11 | else:
12 | print("filtered by detected_filter: {}".format(crawl_datum.brief_info()))
13 | return None
14 |
15 |
16 | class NewsCrawler(wc.RamCrawler):
17 | def __init__(self):
18 | super().__init__(auto_detect=True, detected_filter=RegexDetectedFilter())
19 | self.num_threads = 10
20 | self.add_seed("https://github.blog/")
21 |
22 | def visit(self, page, detected):
23 |
24 | detected.extend(page.links("https://github.blog/[0-9]+.*"))
25 |
26 | if page.match_url("https://github.blog/[0-9]+.*"):
27 | title = page.select("h1.lh-condensed")[0].text.strip()
28 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
29 | print("\nURL: ", page.url)
30 | print("TITLE: ", title)
31 | print("CONTENT: ", content[:50], "...")
32 |
33 |
34 | crawler = NewsCrawler()
35 | crawler.start(10)
36 |
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/webcollector/utils.py:
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1 | # coding=utf-8
2 |
3 | import re
4 |
5 |
6 | def url_matches(url, url_regex):
7 | if isinstance(url_regex, str):
8 | return re.fullmatch(url_regex, url) is not None
9 | else:
10 | return url_regex.fullmatch(url) is not None
11 |
12 |
13 | class RegexRule(object):
14 | def __init__(self):
15 | self.pos_regexes = []
16 | self.neg_regexes = []
17 |
18 | def add(self, regex):
19 | start_char = regex[0]
20 | if start_char == '+':
21 | self.add_pos(regex[1:])
22 | elif start_char == '-':
23 | self.add_neg(regex[1:])
24 | else:
25 | self.add_pos(regex)
26 |
27 | def add_pos(self, pos_regex):
28 | self.pos_regexes.append(re.compile(pos_regex))
29 |
30 | def add_neg(self, neg_regex):
31 | self.neg_regexes.append(re.compile(neg_regex))
32 |
33 | # match rule:
34 | # - must match at least one pos rule
35 | # - must not match any neg rule
36 | def matches(self, url):
37 | for neg_rule in self.neg_regexes:
38 | if neg_rule.fullmatch(url) is not None:
39 | return False
40 | for pos_rule in self.pos_regexes:
41 | if pos_rule.fullmatch(url) is not None:
42 | return True
43 | return False
44 |
45 |
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/webcollector/plugin/net.py:
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1 | # coding=utf-8
2 | from webcollector.config import DEFAULT_USER_AGENT
3 | from webcollector.model import Page
4 | from webcollector.net import Requester
5 | import requests
6 |
7 |
8 | class HttpRequester(Requester):
9 |
10 | def get_response(self, crawl_datum):
11 | headers = {"User-Agent": DEFAULT_USER_AGENT}
12 | response = requests.get(crawl_datum.url, headers=headers)
13 |
14 | code = response.status_code
15 | content = response.content
16 | encoding = response.encoding
17 | content_type = response.headers["Content-Type"]
18 |
19 | crawl_datum.code = code
20 | page = Page(crawl_datum, content, content_type=content_type, http_charset=encoding)
21 |
22 | return page
23 |
24 |
25 | # class AioHttpRequester(Requester):
26 | #
27 | # def __init__(self):
28 | # self.session = None
29 | #
30 | # def create_async_context_manager(self):
31 | # self.session = aiohttp.ClientSession()
32 | # return self.session
33 | #
34 | # def request(self, crawl_datum):
35 | # return self.session.get(
36 | # crawl_datum.url,
37 | # headers={"User-Agent": DEFAULT_USER_AGENT}
38 | # )
39 | #
40 | # async def get_response(self, crawl_datum):
41 | # # async with self.session.get(crawl_datum.url) as response:
42 | # async with self.request(crawl_datum) as response:
43 | # code = response.status
44 | # content = await response.content.read()
45 | # encoding = response.get_encoding()
46 | # content_type = response.content_type
47 | # crawl_datum.code = code
48 | # page = Page(crawl_datum, content, content_type=content_type, http_charset=encoding)
49 | # return page
50 |
51 |
52 |
53 |
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/examples/demo_custom_http_request.py:
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1 | # coding=utf-8
2 |
3 | import webcollector as wc
4 | from webcollector.model import Page
5 | from webcollector.plugin.net import HttpRequester
6 |
7 | import requests
8 |
9 |
10 | class MyRequester(HttpRequester):
11 | def get_response(self, crawl_datum):
12 | # custom http request
13 | headers = {
14 | "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36"
15 | }
16 |
17 | print("sending request with MyRequester")
18 |
19 | # send request and get response
20 | response = requests.get(crawl_datum.url, headers=headers)
21 |
22 | # update code
23 | crawl_datum.code = response.status_code
24 |
25 | # wrap http response as a Page object
26 | page = Page(crawl_datum,
27 | response.content,
28 | content_type=response.headers["Content-Type"],
29 | http_charset=response.encoding)
30 |
31 | return page
32 |
33 |
34 | class NewsCrawler(wc.RamCrawler):
35 | def __init__(self):
36 | super().__init__(auto_detect=True)
37 | self.num_threads = 10
38 |
39 | # set requester to enable MyRequester
40 | self.requester = MyRequester()
41 |
42 | self.add_seed("https://github.blog/")
43 | self.add_regex("+https://github.blog/[0-9]+.*")
44 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
45 |
46 | def visit(self, page, detected):
47 | if page.match_url("https://github.blog/[0-9]+.*"):
48 | title = page.select("h1.lh-condensed")[0].text.strip()
49 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
50 | print("\nURL: ", page.url)
51 | print("TITLE: ", title)
52 | print("CONTENT: ", content[:50], "...")
53 |
54 |
55 | crawler = NewsCrawler()
56 | crawler.start(10)
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/test.py:
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1 | # coding=utf-8
2 |
3 | import asyncio
4 | import requests
5 | import random
6 | import threading
7 |
8 |
9 |
10 | import asyncio
11 | import requests
12 | from concurrent.futures import ThreadPoolExecutor
13 | import time
14 |
15 | url = "http://127.0.0.1:5000"
16 |
17 | loop = asyncio.get_event_loop()
18 |
19 |
20 | async def cor():
21 | print("c-start")
22 | await asyncio.sleep(4)
23 | print("c-end")
24 |
25 |
26 | async def main():
27 | tasks = [loop.create_task(cor()) for _ in range(10)]
28 | print("finish tasks======")
29 | for i, task in enumerate(tasks):
30 | print("start", i)
31 | time.sleep(5)
32 | await task
33 | print("end", i)
34 |
35 | loop.run_until_complete(main())
36 |
37 | adfads
38 |
39 | pool = ThreadPoolExecutor(20)
40 |
41 |
42 |
43 | def request(i):
44 | print("start", i)
45 | time.sleep(5)
46 | text = requests.get(url).text
47 | print("content:", i, text)
48 | print(threading.get_ident())
49 | return text
50 |
51 |
52 | # f0 = loop.run_in_executor(pool, request)
53 | # f1 = loop.run_in_executor(pool, request)
54 | # futures = [loop.run_in_executor(pool, request, i) for i in range(20)]
55 | # futures = [loop.run_in_executor(None, requests.get, "http://127.0.0.1:5000") for _ in range(10)]
56 | # print("======")
57 |
58 |
59 | async def cor(i):
60 | for j in range(20):
61 | future = loop.run_in_executor(pool, request, "{}_{}".format(i, j))
62 | await future
63 | print("cor", i)
64 | print("end-cor", i)
65 |
66 | loop.run_until_complete(asyncio.gather(*[cor(i) for i in range(10)]))
67 |
68 |
69 | # async def main():
70 | # # for future in futures:
71 | # for i in range(10):
72 | # # future = loop.run_in_executor(pool, request)
73 | # await futures[i]
74 | # print("end", i)
75 | #
76 | # loop.run_until_complete(main())
77 |
78 | # async def test():
79 | # print("start")
80 | # # await asyncio.sleep(2)
81 | # request_future = loop.run_in_executor(pool, request)
82 | # result = await request_future
83 | # print("end")
84 | #
85 | #
86 | #
87 | #
88 | # async def main():
89 | # tasks = [loop.create_task(test()) for _ in range(10)]
90 | # for i in range(10):
91 | # await tasks[i]
92 | # print("task end", i)
93 | #
94 | #
95 | # loop.run_until_complete(main())
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/webcollector/plugin/ram.py:
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1 | # coding=utf-8
2 | from webcollector.crawler import AutoDetectCrawler
3 | from webcollector.db_manager import DBManager
4 | from webcollector.generate import Generator
5 | from webcollector.model import CrawlDatum
6 |
7 |
8 | class RamDB(object):
9 | def __init__(self):
10 | self.crawl_db = {}
11 | self.fetch_db = None
12 | self.detect_db = None
13 |
14 |
15 | class RamDBGenerator(Generator):
16 |
17 | def __init__(self, ram_db):
18 | super().__init__()
19 | self.ram_db = ram_db
20 | self.iter = iter(self.ram_db.crawl_db.values())
21 |
22 | def _next(self) -> CrawlDatum:
23 | try:
24 | return next(self.iter)
25 | except StopIteration:
26 | return None
27 |
28 |
29 | class RamDBManager(DBManager):
30 | def __init__(self, ram_db):
31 | self.ram_db = ram_db
32 |
33 | def inject(self, seeds, forced=False):
34 | for seed in seeds:
35 | if isinstance(seed, str):
36 | seed = CrawlDatum(seed)
37 | if not forced and seed.key in self.ram_db.crawl_db:
38 | continue
39 | self.ram_db.crawl_db[seed.key] = seed
40 |
41 | def create_generator(self):
42 | return RamDBGenerator(self.ram_db)
43 |
44 | def init_fetch_and_detect(self):
45 | self.ram_db.fetch_db = {}
46 | self.ram_db.detect_db = {}
47 |
48 | def write_fetch(self, crawl_datum):
49 | self.ram_db.fetch_db[crawl_datum.key] = crawl_datum
50 |
51 | def write_detect(self, crawl_datum):
52 | self.ram_db.detect_db[crawl_datum.key] = crawl_datum
53 |
54 | def merge(self):
55 | print("merging......")
56 | if self.ram_db.fetch_db is not None:
57 | for crawl_datum in self.ram_db.fetch_db.values():
58 | self.ram_db.crawl_db[crawl_datum.key] = crawl_datum
59 | self.ram_db.fetch_db = None
60 |
61 | if self.ram_db.detect_db is not None:
62 | for crawl_datum in self.ram_db.detect_db.values():
63 | if crawl_datum.key not in self.ram_db.crawl_db:
64 | self.ram_db.crawl_db[crawl_datum.key] = crawl_datum
65 | self.ram_db.detect_db = None
66 |
67 |
68 | class RamCrawler(AutoDetectCrawler):
69 | def __init__(self, auto_detect, **kwargs):
70 | self.ram_db = RamDB()
71 | super().__init__(RamDBManager(self.ram_db), auto_detect, **kwargs)
72 |
73 |
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/webcollector/plugin/redis.py:
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1 | # coding=utf-8
2 | from redis import StrictRedis
3 |
4 | from webcollector.crawler import AutoDetectCrawler
5 | from webcollector.db_manager import DBManager
6 | from webcollector.generate import Generator
7 | from webcollector.model import CrawlDatum
8 |
9 |
10 | class RedisDBGenerator(Generator):
11 |
12 | def __init__(self, redis_db_manager):
13 | super().__init__()
14 | self.history_keys = set()
15 | self.iter = redis_db_manager.redis_client.hscan_iter(
16 | redis_db_manager.crawl_db
17 | )
18 |
19 | def _next(self) -> CrawlDatum:
20 | try:
21 | while True:
22 | key, crawl_datum_json = next(self.iter)
23 | if key in self.history_keys:
24 | continue
25 | else:
26 | self.history_keys.add(key)
27 | return CrawlDatum.from_json(crawl_datum_json)
28 | except StopIteration:
29 | return None
30 |
31 |
32 | class RedisDBManager(DBManager):
33 | def __init__(self, redis_client: StrictRedis, db_prefix):
34 | self.redis_client = redis_client
35 | self.db_prefix = db_prefix
36 | self.crawl_db = "{}_crawl".format(db_prefix)
37 | self.fetch_db = "{}_fetch".format(db_prefix)
38 | self.detect_db = "{}_detect".format(db_prefix)
39 |
40 | def open(self):
41 | pass
42 |
43 | def close(self):
44 | pass
45 |
46 | def clear(self):
47 | self.redis_client.delete(self.crawl_db)
48 | self.redis_client.delete(self.fetch_db)
49 | self.redis_client.delete(self.detect_db)
50 |
51 | def inject(self, seeds, forced=False):
52 | for seed in seeds:
53 | if isinstance(seed, str):
54 | seed = CrawlDatum(seed)
55 | if not forced and self.redis_client.hexists(self.crawl_db, seed.key):
56 | continue
57 | self.redis_client.hset(self.crawl_db, seed.key, seed.to_json())
58 |
59 | def create_generator(self):
60 | return RedisDBGenerator(self)
61 |
62 | def init_fetch_and_detect(self):
63 | pass
64 |
65 | def write_fetch(self, crawl_datum):
66 | self.redis_client.hset(self.fetch_db, crawl_datum.key, crawl_datum.to_json())
67 |
68 | def write_detect(self, crawl_datum):
69 | self.redis_client.hset(self.detect_db, crawl_datum.key, crawl_datum.to_json())
70 |
71 | def merge(self):
72 | print("merging......")
73 | if self.redis_client.exists(self.fetch_db):
74 | for _, crawl_datum_json in self.redis_client.hscan_iter(self.fetch_db):
75 | crawl_datum = CrawlDatum.from_json(crawl_datum_json)
76 | self.redis_client.hset(self.crawl_db, crawl_datum.key, crawl_datum.to_json())
77 | self.redis_client.delete(self.fetch_db)
78 |
79 | if self.redis_client.exists(self.detect_db):
80 | for key, crawl_datum_json in self.redis_client.hscan_iter(self.detect_db):
81 | if not self.redis_client.hexists(self.crawl_db, key):
82 | crawl_datum = CrawlDatum.from_json(crawl_datum_json)
83 | self.redis_client.hset(self.crawl_db, crawl_datum.key, crawl_datum.to_json())
84 | self.redis_client.delete(self.detect_db)
85 |
86 |
87 | class RedisCrawler(AutoDetectCrawler):
88 | def __init__(self, redis_client, db_prefix, auto_detect, **kwargs):
89 | super().__init__(RedisDBManager(redis_client, db_prefix), auto_detect, **kwargs)
90 |
91 |
--------------------------------------------------------------------------------
/webcollector/fetch.py:
--------------------------------------------------------------------------------
1 | # coding=utf-8
2 | import queue
3 | import asyncio
4 | import logging
5 | from webcollector.model import Page, CrawlDatums, CrawlDatum
6 |
7 | logger = logging.getLogger(__name__)
8 |
9 |
10 | class Fetcher(object):
11 | def __init__(self,
12 | db_manager,
13 | requester,
14 | execute_func,
15 | generator_filter=None,
16 | detected_filter=None,
17 | num_threads=10):
18 | self.fetch_queue = None
19 | self.feed_stopped = None
20 | self.generator = None
21 | self.generator_filter = generator_filter
22 | self.detected_filter = detected_filter
23 | self.feeder = None
24 | self.buffer_size = 1000
25 | self.db_manager = db_manager
26 |
27 | self.requester = requester
28 | self.execute_func = execute_func
29 | self.num_threads = num_threads
30 |
31 | self.loop = None
32 |
33 |
34 | async def async_start(self):
35 | self.fetch_queue = queue.Queue()
36 | self.feed_stopped = False
37 | self.db_manager.open()
38 | self.db_manager.init_fetch_and_detect()
39 | self.generator = self.db_manager.create_generator()
40 | self.generator.generator_filter = self.generator_filter
41 |
42 | # async with self.requester.create_async_context_manager():
43 | # coroutines = [self.fetch_coroutine(self.execute_func) for _ in range(self.num_threads)]
44 | # await asyncio.gather(*coroutines)
45 | with self.requester:
46 | coroutines = [self.fetch_coroutine(self.execute_func) for _ in range(self.num_threads)]
47 | await asyncio.gather(*coroutines)
48 | self.db_manager.close()
49 |
50 | def start(self):
51 | self.loop = asyncio.get_event_loop()
52 | self.loop.run_until_complete(self.async_start())
53 | return self.generator.num_generated
54 |
55 | def feed(self):
56 | for i in range(self.buffer_size):
57 | crawl_datum = self.generator.next()
58 | if crawl_datum is None:
59 | self.feed_stopped = True
60 | return
61 | else:
62 | self.fetch_queue.put(crawl_datum)
63 |
64 | async def fetch_coroutine(self, execute_func):
65 | while True:
66 | if self.fetch_queue.empty():
67 | if self.feed_stopped:
68 | break
69 | self.feed()
70 | else:
71 | crawl_datum = self.fetch_queue.get(block=False)
72 | try:
73 | # loop = asyncio.get_event_loop()
74 | request_future = self.loop.run_in_executor(None, self.requester.get_response, crawl_datum)
75 | page = await request_future
76 | # page = await self.requester.get_response(crawl_datum)
77 | detected = CrawlDatums()
78 | execute_func(page, detected)
79 |
80 | crawl_datum.status = CrawlDatum.STATUS_DB_SUCCESS
81 |
82 | if self.detected_filter is not None:
83 | filtered_detected = CrawlDatums()
84 | for detected_crawl_datum in detected:
85 | detected_crawl_datum = self.detected_filter.filter(detected_crawl_datum)
86 | if detected_crawl_datum is not None:
87 | filtered_detected.append(detected_crawl_datum)
88 | else:
89 | filtered_detected = detected
90 |
91 | for detected_crawl_datum in filtered_detected:
92 | self.db_manager.write_detect(detected_crawl_datum)
93 | logger.info("done: {}".format(crawl_datum.brief_info()))
94 | except Exception as e:
95 | logger.error("failed: {}".format(crawl_datum.brief_info()), exc_info=True)
96 | crawl_datum.status = CrawlDatum.STATUS_DB_FAILED
97 |
98 | crawl_datum.num_fetched += 1
99 | self.db_manager.write_fetch(crawl_datum)
100 |
--------------------------------------------------------------------------------
/webcollector/crawler.py:
--------------------------------------------------------------------------------
1 | # coding=utf-8
2 | from urllib.parse import urljoin
3 |
4 | from webcollector.fetch import Fetcher
5 | from webcollector.generate import StatusGeneratorFilter
6 | from webcollector.model import Page, CrawlDatums
7 | from webcollector.plugin.net import HttpRequester
8 | from webcollector.utils import RegexRule
9 |
10 | import logging
11 | import time
12 |
13 | logger = logging.getLogger(__name__)
14 |
15 |
16 | class Crawler(object):
17 | def __init__(self,
18 | db_manager,
19 | requester=HttpRequester(),
20 | generator_filter=StatusGeneratorFilter(),
21 | detected_filter=None):
22 | self.db_manager = db_manager
23 | self.requester = requester
24 | self.generator_filter = generator_filter
25 | self.detected_filter = detected_filter
26 | self.fetcher = None
27 | self.num_threads = 10
28 | self.resumable = None
29 |
30 | self.seeds = CrawlDatums()
31 | self.forced_seeds = CrawlDatums()
32 |
33 | def add_seed(self, url_or_datum, type=None, forced=False):
34 | if forced:
35 | return self.forced_seeds.append(url_or_datum).set_type(type)
36 | else:
37 | return self.seeds.append(url_or_datum).set_type(type)
38 |
39 | def add_seeds(self, urls_or_datums, type=None, forced=False):
40 | crawl_datums = []
41 | for url_or_datum in urls_or_datums:
42 | crawl_datum = self.add_seed(url_or_datum, type=type, forced=forced)
43 | crawl_datums.append(crawl_datum)
44 | return crawl_datums
45 |
46 | def inject(self):
47 | self.db_manager.inject(self.seeds, forced=False)
48 | self.db_manager.inject(self.forced_seeds, forced=True)
49 |
50 | # def add_seed_and_return(self, url_or_datum):
51 | # crawl_datum = CrawlDatum.convert_from_item(url_or_datum)
52 | # self.seeds.append(crawl_datum)
53 | # return crawl_datum
54 |
55 | # def add_seeds_and_return(self, urls_or_datums):
56 | # crawl_datums = CrawlDatum.convert_from_list(urls_or_datums)
57 | # self.seeds.extend(crawl_datums)
58 | # return crawl_datums
59 |
60 | def execute(self, page, detected):
61 | pass
62 |
63 | def start_once(self, depth_index):
64 | self.db_manager.merge()
65 | self.fetcher = Fetcher(
66 | self.db_manager,
67 | self.requester,
68 | execute_func=self.execute,
69 | generator_filter=self.generator_filter,
70 | detected_filter=self.detected_filter,
71 | num_threads=self.num_threads
72 | )
73 | return self.fetcher.start()
74 |
75 | def start(self, depth):
76 | if not self.resumable:
77 | self.db_manager.clear()
78 | if len(self.seeds) == 0 and len(self.forced_seeds) == 0:
79 | raise Exception("Please add at least one seed")
80 | self.inject()
81 | for depth_index in range(depth):
82 | print("start depth {}".format(depth_index))
83 | start_time = time.time()
84 | num_generated = self.start_once(depth_index)
85 | cost_time = time.time() - start_time
86 | logger.info("depth {} finish: \n\ttotal urls:\t{}\n\ttotal time:\t{} seconds"
87 | .format(depth_index, num_generated, cost_time))
88 | if num_generated == 0:
89 | break
90 |
91 |
92 | class AutoDetectCrawler(Crawler):
93 |
94 | def __init__(self, db_manager, auto_detect, **kwargs):
95 | super().__init__(db_manager, **kwargs)
96 | self.auto_detect = auto_detect
97 | self.regex_rule = RegexRule()
98 |
99 | def add_regex(self, regex):
100 | self.regex_rule.add(regex)
101 |
102 | def execute(self, page, detected):
103 | self.visit(page, detected)
104 | if self.auto_detect:
105 | self.detect_links(page, detected)
106 |
107 | def visit(self, page, detected):
108 | pass
109 |
110 | def detect_links(self, page: Page, detected):
111 | if page.content_type is not None and "text/html" in page.content_type:
112 | link_eles = page.select("a[href]")
113 | for link_ele in link_eles:
114 | href = link_ele["href"]
115 | abs_href = urljoin(page.url, href)
116 | if self.regex_rule.matches(abs_href):
117 | detected.append(abs_href)
118 |
--------------------------------------------------------------------------------
/webcollector/model.py:
--------------------------------------------------------------------------------
1 | # coding=utf-8
2 | from urllib.parse import urljoin
3 | import chardet
4 | from bs4 import BeautifulSoup
5 | import json
6 |
7 |
8 | # A CrawlDatum corresponds to a task description (usually for a webpage)
9 | from webcollector.utils import url_matches
10 |
11 |
12 | class CrawlDatum(object):
13 | STATUS_DB_UNEXECUTED = 0
14 | STATUS_DB_FAILED = 1
15 | STATUS_DB_SUCCESS = 5
16 | CODE_NOT_SET = -1
17 |
18 | META_KEY_SYS_TYPE = "sys_type"
19 |
20 | def __init__(self, url,
21 | key=None,
22 | type=None,
23 | meta_dict=None,
24 | code=CODE_NOT_SET,
25 | status=STATUS_DB_UNEXECUTED,
26 | num_fetched=0):
27 | self.url = url
28 | self.key = key if key is not None else url
29 | self.type = type
30 | self.meta_dict = meta_dict
31 | self.code = code
32 | self.status = status
33 | self.num_fetched = num_fetched
34 |
35 | def set_key(self, key):
36 | self.key = key
37 | return self
38 |
39 | def set_type(self, type):
40 | self.type = type
41 | return self
42 |
43 | def set_url(self, url):
44 | self.url = url
45 | return self
46 |
47 | def set_meta_dict(self, meta_dict):
48 | self.meta_dict = meta_dict
49 | return self.meta_dict
50 |
51 | def set_meta_item(self, meta_key, meta_value):
52 | if self.meta_dict is None:
53 | self.meta_dict = {}
54 | self.meta_dict[meta_key] = meta_value
55 | return self
56 |
57 | def match_type(self, type):
58 | return self.type == type
59 |
60 | def match_url(self, url_regex):
61 | return url_matches(self.url, url_regex)
62 |
63 | @classmethod
64 | def convert_from_item(cls, url_or_datum):
65 | if isinstance(url_or_datum, CrawlDatum):
66 | return url_or_datum
67 | else:
68 | return CrawlDatum(url_or_datum)
69 |
70 | def brief_info(self):
71 | infos = []
72 | if self.code != CrawlDatum.CODE_NOT_SET:
73 | infos.append("[{}]".format(self.code))
74 | infos.append("Key: {} (URL: {})".format(self.key, self.url))
75 | return " ".join(infos)
76 |
77 | def to_dict(self):
78 | dict_data = {
79 | "url": self.url,
80 | "key": self.key,
81 | "type": self.type,
82 | "meta_dict": self.meta_dict,
83 | "code": self.code,
84 | "status": self.status,
85 | "num_fetched": self.num_fetched
86 | }
87 | return dict_data
88 |
89 | @classmethod
90 | def from_dict(cls, dict_data):
91 | return CrawlDatum(
92 | url=dict_data["url"],
93 | key=dict_data["key"],
94 | type=dict_data["type"],
95 | meta_dict=dict_data["meta_dict"],
96 | code=dict_data["code"],
97 | status=dict_data["status"],
98 | num_fetched=dict_data["num_fetched"]
99 | )
100 |
101 | def to_json(self):
102 | return json.dumps(self.to_dict())
103 |
104 | @classmethod
105 | def from_json(cls, json_str):
106 | return CrawlDatum.from_dict(json.loads(json_str))
107 |
108 |
109 | class CrawlDatums(list):
110 |
111 | def append(self, url_or_datum):
112 | if isinstance(url_or_datum, CrawlDatum):
113 | crawl_datum = url_or_datum
114 | else:
115 | crawl_datum = CrawlDatum(url_or_datum)
116 | super().append(crawl_datum)
117 | return crawl_datum
118 |
119 | def extend(self, url_or_datums):
120 | crawl_datums = []
121 | for url_or_datum in url_or_datums:
122 | crawl_datums.append(self.append(url_or_datum))
123 | return crawl_datums
124 |
125 | def set_type(self, type):
126 | for crawl_datum in self:
127 | crawl_datum.type = type
128 |
129 | def set_meta_item(self, meta_key, meta_value):
130 | for crawl_datum in self:
131 | crawl_datum.set_meta_item(meta_key, meta_value)
132 |
133 | @classmethod
134 | def convert_from_list(cls, urls_or_datums):
135 | return [CrawlDatum.convert_from_item(item) for item in urls_or_datums]
136 |
137 |
138 | # A Page corresponds to the response of a http request
139 | class Page(object):
140 | def __init__(self, crawl_datum, content, content_type=None, http_charset=None):
141 | self.crawl_datum = crawl_datum
142 | # self.code = code
143 | self.content = content
144 | self.content_type = content_type
145 | self.http_charset = http_charset
146 | self._html = None
147 | self._detected_charset = None
148 | self._doc = None
149 |
150 | def abs_url(self, abs_or_relative_url):
151 | return urljoin(self.url, abs_or_relative_url)
152 |
153 | @property
154 | def code(self):
155 | return self.crawl_datum.code
156 |
157 | @property
158 | def url(self):
159 | return self.crawl_datum.url
160 |
161 | @property
162 | def doc(self):
163 | if self._doc is not None:
164 | return self._doc
165 | html = self.html
166 | if html is None:
167 | return None
168 | self._doc = BeautifulSoup(html, features="html5lib")
169 | return self._doc
170 |
171 | def select(self, css_selector):
172 | soup = self.doc
173 | return soup.select(css_selector)
174 |
175 | @property
176 | def html(self):
177 | # cache
178 | if self._html is not None:
179 | return self._html
180 | self._html = self.decode_content()
181 | return self._html
182 |
183 | @property
184 | def type(self):
185 | return self.crawl_datum.type
186 |
187 | def links(self, url_regex=None):
188 | a_eles = self.doc.select("a[href]")
189 | urls = [self.abs_url(a_ele["href"]) for a_ele in a_eles]
190 | if url_regex is None:
191 | return urls
192 | else:
193 | urls = [url for url in urls if url_matches(url, url_regex)]
194 | return urls
195 |
196 | def decode_content(self, charset=None):
197 | # None Content
198 | if self.content is None:
199 | return None
200 | # Manual
201 | if charset is not None:
202 | return self.content.decode(charset)
203 |
204 | # Http Charset
205 | if self.http_charset is not None:
206 | return self.content.decode(self.http_charset)
207 |
208 | # detect
209 | if self._detected_charset is None:
210 | self._detected_charset = chardet.detect(self.content)['encoding']
211 | if self._detected_charset is None:
212 | return self.content.decode("utf-8")
213 |
214 | return self.content.decode(self._detected_charset)
215 |
216 | def match_type(self, type):
217 | return self.crawl_datum.match_type(type)
218 |
219 | def match_url(self, url_regex):
220 | return self.crawl_datum.match_url(url_regex)
221 |
--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 | # WebCollector-Python
2 |
3 | WebCollector-Python is an open source web crawler framework based on Python.It provides some simple interfaces for crawling the Web,you can setup a multi-threaded web crawler in less than 5 minutes.
4 |
5 |
6 | ## HomePage
7 |
8 | [https://github.com/CrawlScript/WebCollector-Python](https://github.com/CrawlScript/WebCollector-Python)
9 |
10 | ## WebCollector Java Version
11 |
12 | For better efficiency, WebCollector Java Version is recommended: [https://github.com/CrawlScript/WebCollector](https://github.com/CrawlScript/WebCollector)
13 |
14 |
15 | ## Installation
16 |
17 | ### pip
18 |
19 | ```bash
20 | pip install https://github.com/CrawlScript/WebCollector-Python/archive/master.zip
21 | ```
22 |
23 | ## Example Index
24 |
25 |
26 | ### Basic
27 |
28 | + [demo_auto_news_crawler.py](examples/demo_auto_news_crawler.py)
29 | + [demo_manual_news_crawler.py](examples/demo_manual_news_crawler.py)
30 |
31 | ## Quickstart
32 |
33 | ### Automatically Detecting URLs
34 |
35 | [demo_auto_news_crawler.py](examples/demo_auto_news_crawler.py):
36 |
37 | ```python
38 | # coding=utf-8
39 | import webcollector as wc
40 |
41 |
42 | class NewsCrawler(wc.RamCrawler):
43 | def __init__(self):
44 | super().__init__(auto_detect=True)
45 | self.num_threads = 10
46 | self.add_seed("https://github.blog/")
47 | self.add_regex("+https://github.blog/[0-9]+.*")
48 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
49 |
50 | def visit(self, page, detected):
51 | if page.match_url("https://github.blog/[0-9]+.*"):
52 | title = page.select("h1.lh-condensed")[0].text.strip()
53 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
54 | print("\nURL: ", page.url)
55 | print("TITLE: ", title)
56 | print("CONTENT: ", content[:50], "...")
57 |
58 |
59 | crawler = NewsCrawler()
60 | crawler.start(10)
61 | ```
62 |
63 | ### Manually Detecting URLs
64 |
65 | [demo_manual_news_crawler.py](examples/demo_manual_news_crawler.py):
66 |
67 | ```python
68 | # coding=utf-8
69 | import webcollector as wc
70 |
71 |
72 | class NewsCrawler(wc.RamCrawler):
73 | def __init__(self):
74 | super().__init__(auto_detect=False)
75 | self.num_threads = 10
76 | self.add_seed("https://github.blog/")
77 |
78 | def visit(self, page, detected):
79 |
80 | detected.extend(page.links("https://github.blog/[0-9]+.*"))
81 |
82 | if page.match_url("https://github.blog/[0-9]+.*"):
83 | title = page.select("h1.lh-condensed")[0].text.strip()
84 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
85 | print("\nURL: ", page.url)
86 | print("TITLE: ", title)
87 | print("CONTENT: ", content[:50], "...")
88 |
89 |
90 | crawler = NewsCrawler()
91 | crawler.start(10)
92 | ```
93 |
94 | ### Filter Detected URLs by detected_filter Plugin
95 |
96 | [demo_detected_filter.py](examples/demo_detected_filter.py):
97 |
98 | ```python
99 | # coding=utf-8
100 | import webcollector as wc
101 | from webcollector.filter import Filter
102 | import re
103 |
104 |
105 | class RegexDetectedFilter(Filter):
106 | def filter(self, crawl_datum):
107 | if re.fullmatch("https://github.blog/2019-02.*", crawl_datum.url):
108 | return crawl_datum
109 | else:
110 | print("filtered by detected_filter: {}".format(crawl_datum.brief_info()))
111 | return None
112 |
113 |
114 | class NewsCrawler(wc.RamCrawler):
115 | def __init__(self):
116 | super().__init__(auto_detect=True, detected_filter=RegexDetectedFilter())
117 | self.num_threads = 10
118 | self.add_seed("https://github.blog/")
119 |
120 | def visit(self, page, detected):
121 |
122 | detected.extend(page.links("https://github.blog/[0-9]+.*"))
123 |
124 | if page.match_url("https://github.blog/[0-9]+.*"):
125 | title = page.select("h1.lh-condensed")[0].text.strip()
126 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
127 | print("\nURL: ", page.url)
128 | print("TITLE: ", title)
129 | print("CONTENT: ", content[:50], "...")
130 |
131 |
132 | crawler = NewsCrawler()
133 | crawler.start(10)
134 | ```
135 |
136 |
137 | ### Resume Crawling by RedisCrawler
138 |
139 | [demo_redis_crawler.py](examples/demo_redis_crawler.py):
140 |
141 |
142 | ```python
143 | # coding=utf-8
144 | from redis import StrictRedis
145 | import webcollector as wc
146 |
147 |
148 | class NewsCrawler(wc.RedisCrawler):
149 |
150 | def __init__(self):
151 | super().__init__(redis_client=StrictRedis("127.0.0.1"),
152 | db_prefix="news",
153 | auto_detect=True)
154 | self.num_threads = 10
155 | self.resumable = True # you can resume crawling after shutdown
156 | self.add_seed("https://github.blog/")
157 | self.add_regex("+https://github.blog/[0-9]+.*")
158 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
159 |
160 | def visit(self, page, detected):
161 | if page.match_url("https://github.blog/[0-9]+.*"):
162 | title = page.select("h1.lh-condensed")[0].text.strip()
163 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
164 | print("\nURL: ", page.url)
165 | print("TITLE: ", title)
166 | print("CONTENT: ", content[:50], "...")
167 |
168 |
169 | crawler = NewsCrawler()
170 | crawler.start(10)
171 |
172 | ```
173 |
174 | ### Custom Http Request with Requests
175 |
176 | [demo_custom_http_request.py](examples/demo_custom_http_request.py):
177 |
178 |
179 | ```python
180 | # coding=utf-8
181 |
182 | import webcollector as wc
183 | from webcollector.model import Page
184 | from webcollector.plugin.net import HttpRequester
185 |
186 | import requests
187 |
188 |
189 | class MyRequester(HttpRequester):
190 | def get_response(self, crawl_datum):
191 | # custom http request
192 | headers = {
193 | "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36"
194 | }
195 |
196 | print("sending request with MyRequester")
197 |
198 | # send request and get response
199 | response = requests.get(crawl_datum.url, headers=headers)
200 |
201 | # update code
202 | crawl_datum.code = response.status_code
203 |
204 | # wrap http response as a Page object
205 | page = Page(crawl_datum,
206 | response.content,
207 | content_type=response.headers["Content-Type"],
208 | http_charset=response.encoding)
209 |
210 | return page
211 |
212 |
213 | class NewsCrawler(wc.RamCrawler):
214 | def __init__(self):
215 | super().__init__(auto_detect=True)
216 | self.num_threads = 10
217 |
218 | # set requester to enable MyRequester
219 | self.requester = MyRequester()
220 |
221 | self.add_seed("https://github.blog/")
222 | self.add_regex("+https://github.blog/[0-9]+.*")
223 | self.add_regex("-.*#.*") # do not detect urls that contain "#"
224 |
225 | def visit(self, page, detected):
226 | if page.match_url("https://github.blog/[0-9]+.*"):
227 | title = page.select("h1.lh-condensed")[0].text.strip()
228 | content = page.select("div.markdown-body")[0].text.replace("\n", " ").strip()
229 | print("\nURL: ", page.url)
230 | print("TITLE: ", title)
231 | print("CONTENT: ", content[:50], "...")
232 |
233 |
234 | crawler = NewsCrawler()
235 | crawler.start(10)
236 | ```
--------------------------------------------------------------------------------
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559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 |
563 | 14. Revised Versions of this License.
564 |
565 | The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time. Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 |
570 | Each version is given a distinguishing version number. If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation. If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 |
579 | If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 |
584 | Later license versions may give you additional or different
585 | permissions. However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 |
589 | 15. Disclaimer of Warranty.
590 |
591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 |
600 | 16. Limitation of Liability.
601 |
602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 |
612 | 17. Interpretation of Sections 15 and 16.
613 |
614 | If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 |
621 | END OF TERMS AND CONDITIONS
622 |
623 | How to Apply These Terms to Your New Programs
624 |
625 | If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 |
629 | To do so, attach the following notices to the program. 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 |
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