├── .github └── workflows │ └── lint-and-test-code.yml ├── .gitignore ├── CHANGELOG.md ├── LICENSE ├── README.md ├── build.edn ├── deps.edn ├── img ├── transductio-logo-1024.png ├── transductio-logo-150.png ├── transductio-logo-300.png └── transductio-logo.svg ├── src └── systems │ └── thoughtfull │ └── transductio.clj └── test └── systems └── thoughtfull └── transductio_test.clj /.github/workflows/lint-and-test-code.yml: -------------------------------------------------------------------------------- 1 | name: Lint and test code 2 | on: [push] 3 | jobs: 4 | lint: 5 | name: Lint code 6 | runs-on: ubuntu-latest 7 | steps: 8 | - name: Checkout code 9 | uses: actions/checkout@v4 10 | - name: Setup Java 11 | uses: actions/setup-java@v4 12 | with: 13 | distribution: adopt 14 | java-version: 17 15 | - name: Setup Clojure 16 | uses: DeLaGuardo/setup-clojure@13.2 17 | with: 18 | cli: 1.12.0.1479 19 | clj-kondo: 2025.02.20 20 | - name: Cache Clojure dependencies 21 | uses: actions/cache@v3 22 | with: 23 | path: | 24 | ~/.m2/repository 25 | ~/.gitlibs 26 | ~/.deps.clj 27 | key: cljdeps-${{ hashFiles('deps.edn') }} 28 | restore-keys: cljdeps- 29 | - name: Lint code 30 | run: | 31 | (echo '```'; 32 | clj-kondo --lint src --lint test; 33 | echo '```') >>$GITHUB_STEP_SUMMARY 34 | test: 35 | name: Test code 36 | runs-on: ubuntu-latest 37 | steps: 38 | - name: Checkout code 39 | uses: actions/checkout@v4 40 | - name: Setup Java 41 | uses: actions/setup-java@v4 42 | with: 43 | distribution: adopt 44 | java-version: 17 45 | - name: Setup Clojure 46 | uses: DeLaGuardo/setup-clojure@13.2 47 | with: 48 | cli: 1.12.0.1479 49 | clj-kondo: 2025.02.20 50 | - name: Cache Clojure dependencies 51 | uses: actions/cache@v3 52 | with: 53 | path: | 54 | ~/.m2/repository 55 | ~/.gitlibs 56 | ~/.deps.clj 57 | key: cljdeps-${{ hashFiles('deps.edn') }} 58 | restore-keys: cljdeps- 59 | - name: Test code 60 | run: | 61 | (echo '```'; 62 | clojure -X:test; 63 | echo '```') >>$GITHUB_STEP_SUMMARY 64 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | /.cpcache/ 2 | /.nrepl-port 3 | /target/ 4 | -------------------------------------------------------------------------------- /CHANGELOG.md: -------------------------------------------------------------------------------- 1 | # Changelog 2 | 3 | All notable changes to this project will be documented in this file. 4 | 5 | The format is based on [Keep a Changelog 1.1.0](https://keepachangelog.com/en/1.1.0/), and this 6 | project adheres to [Semantic Versioning 2.0.0](https://semver.org/spec/v2.0.0.html). 7 | 8 | ## [Unreleased] 9 | 10 | ## [1.1.0] - 2025-03-16 11 | 12 | ### Added 13 | 14 | - clojure-decoder decodes Clojure data from a java.io.PushbackReader 15 | - clojure-encoder encodes Clojure data to a java.io.Writer 16 | - edn-decoder decodes EDN data from a java.io.PushbackReader 17 | 18 | ## [1.0.0] - 2025-03-15 19 | 20 | ### Added 21 | 22 | - Initial release with core functions (decoder, encoder) along with some convenience functions 23 | 24 | [unreleased]: https://github.com/thoughtfull-clojure/transductio/compare/v1.1.0...main 25 | [1.1.0]: https://github.com/thoughtfull-clojure/transductio/compare/v1.0.0...v1.1.0 26 | [1.0.0]: https://github.com/thoughtfull-clojure/transductio/releases/tag/v1.0.0 27 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Mozilla Public License Version 2.0 2 | ================================== 3 | 4 | 1. Definitions 5 | -------------- 6 | 7 | 1.1. "Contributor" 8 | means each individual or legal entity that creates, contributes to 9 | the creation of, or owns Covered Software. 10 | 11 | 1.2. "Contributor Version" 12 | means the combination of the Contributions of others (if any) used 13 | by a Contributor and that particular Contributor's Contribution. 14 | 15 | 1.3. "Contribution" 16 | means Covered Software of a particular Contributor. 17 | 18 | 1.4. "Covered Software" 19 | means Source Code Form to which the initial Contributor has attached 20 | the notice in Exhibit A, the Executable Form of such Source Code 21 | Form, and Modifications of such Source Code Form, in each case 22 | including portions thereof. 23 | 24 | 1.5. "Incompatible With Secondary Licenses" 25 | means 26 | 27 | (a) that the initial Contributor has attached the notice described 28 | in Exhibit B to the Covered Software; or 29 | 30 | (b) that the Covered Software was made available under the terms of 31 | version 1.1 or earlier of the License, but not also under the 32 | terms of a Secondary License. 33 | 34 | 1.6. "Executable Form" 35 | means any form of the work other than Source Code Form. 36 | 37 | 1.7. "Larger Work" 38 | means a work that combines Covered Software with other material, in 39 | a separate file or files, that is not Covered Software. 40 | 41 | 1.8. "License" 42 | means this document. 43 | 44 | 1.9. "Licensable" 45 | means having the right to grant, to the maximum extent possible, 46 | whether at the time of the initial grant or subsequently, any and 47 | all of the rights conveyed by this License. 48 | 49 | 1.10. "Modifications" 50 | means any of the following: 51 | 52 | (a) any file in Source Code Form that results from an addition to, 53 | deletion from, or modification of the contents of Covered 54 | Software; or 55 | 56 | (b) any new file in Source Code Form that contains any Covered 57 | Software. 58 | 59 | 1.11. "Patent Claims" of a Contributor 60 | means any patent claim(s), including without limitation, method, 61 | process, and apparatus claims, in any patent Licensable by such 62 | Contributor that would be infringed, but for the grant of the 63 | License, by the making, using, selling, offering for sale, having 64 | made, import, or transfer of either its Contributions or its 65 | Contributor Version. 66 | 67 | 1.12. "Secondary License" 68 | means either the GNU General Public License, Version 2.0, the GNU 69 | Lesser General Public License, Version 2.1, the GNU Affero General 70 | Public License, Version 3.0, or any later versions of those 71 | licenses. 72 | 73 | 1.13. "Source Code Form" 74 | means the form of the work preferred for making modifications. 75 | 76 | 1.14. "You" (or "Your") 77 | means an individual or a legal entity exercising rights under this 78 | License. For legal entities, "You" includes any entity that 79 | controls, is controlled by, or is under common control with You. For 80 | purposes of this definition, "control" means (a) the power, direct 81 | or indirect, to cause the direction or management of such entity, 82 | whether by contract or otherwise, or (b) ownership of more than 83 | fifty percent (50%) of the outstanding shares or beneficial 84 | ownership of such entity. 85 | 86 | 2. License Grants and Conditions 87 | -------------------------------- 88 | 89 | 2.1. Grants 90 | 91 | Each Contributor hereby grants You a world-wide, royalty-free, 92 | non-exclusive license: 93 | 94 | (a) under intellectual property rights (other than patent or trademark) 95 | Licensable by such Contributor to use, reproduce, make available, 96 | modify, display, perform, distribute, and otherwise exploit its 97 | Contributions, either on an unmodified basis, with Modifications, or 98 | as part of a Larger Work; and 99 | 100 | (b) under Patent Claims of such Contributor to make, use, sell, offer 101 | for sale, have made, import, and otherwise transfer either its 102 | Contributions or its Contributor Version. 103 | 104 | 2.2. Effective Date 105 | 106 | The licenses granted in Section 2.1 with respect to any Contribution 107 | become effective for each Contribution on the date the Contributor first 108 | distributes such Contribution. 109 | 110 | 2.3. Limitations on Grant Scope 111 | 112 | The licenses granted in this Section 2 are the only rights granted under 113 | this License. No additional rights or licenses will be implied from the 114 | distribution or licensing of Covered Software under this License. 115 | Notwithstanding Section 2.1(b) above, no patent license is granted by a 116 | Contributor: 117 | 118 | (a) for any code that a Contributor has removed from Covered Software; 119 | or 120 | 121 | (b) for infringements caused by: (i) Your and any other third party's 122 | modifications of Covered Software, or (ii) the combination of its 123 | Contributions with other software (except as part of its Contributor 124 | Version); or 125 | 126 | (c) under Patent Claims infringed by Covered Software in the absence of 127 | its Contributions. 128 | 129 | This License does not grant any rights in the trademarks, service marks, 130 | or logos of any Contributor (except as may be necessary to comply with 131 | the notice requirements in Section 3.4). 132 | 133 | 2.4. Subsequent Licenses 134 | 135 | No Contributor makes additional grants as a result of Your choice to 136 | distribute the Covered Software under a subsequent version of this 137 | License (see Section 10.2) or under the terms of a Secondary License (if 138 | permitted under the terms of Section 3.3). 139 | 140 | 2.5. Representation 141 | 142 | Each Contributor represents that the Contributor believes its 143 | Contributions are its original creation(s) or it has sufficient rights 144 | to grant the rights to its Contributions conveyed by this License. 145 | 146 | 2.6. Fair Use 147 | 148 | This License is not intended to limit any rights You have under 149 | applicable copyright doctrines of fair use, fair dealing, or other 150 | equivalents. 151 | 152 | 2.7. Conditions 153 | 154 | Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted 155 | in Section 2.1. 156 | 157 | 3. Responsibilities 158 | ------------------- 159 | 160 | 3.1. Distribution of Source Form 161 | 162 | All distribution of Covered Software in Source Code Form, including any 163 | Modifications that You create or to which You contribute, must be under 164 | the terms of this License. You must inform recipients that the Source 165 | Code Form of the Covered Software is governed by the terms of this 166 | License, and how they can obtain a copy of this License. You may not 167 | attempt to alter or restrict the recipients' rights in the Source Code 168 | Form. 169 | 170 | 3.2. Distribution of Executable Form 171 | 172 | If You distribute Covered Software in Executable Form then: 173 | 174 | (a) such Covered Software must also be made available in Source Code 175 | Form, as described in Section 3.1, and You must inform recipients of 176 | the Executable Form how they can obtain a copy of such Source Code 177 | Form by reasonable means in a timely manner, at a charge no more 178 | than the cost of distribution to the recipient; and 179 | 180 | (b) You may distribute such Executable Form under the terms of this 181 | License, or sublicense it under different terms, provided that the 182 | license for the Executable Form does not attempt to limit or alter 183 | the recipients' rights in the Source Code Form under this License. 184 | 185 | 3.3. Distribution of a Larger Work 186 | 187 | You may create and distribute a Larger Work under terms of Your choice, 188 | provided that You also comply with the requirements of this License for 189 | the Covered Software. If the Larger Work is a combination of Covered 190 | Software with a work governed by one or more Secondary Licenses, and the 191 | Covered Software is not Incompatible With Secondary Licenses, this 192 | License permits You to additionally distribute such Covered Software 193 | under the terms of such Secondary License(s), so that the recipient of 194 | the Larger Work may, at their option, further distribute the Covered 195 | Software under the terms of either this License or such Secondary 196 | License(s). 197 | 198 | 3.4. Notices 199 | 200 | You may not remove or alter the substance of any license notices 201 | (including copyright notices, patent notices, disclaimers of warranty, 202 | or limitations of liability) contained within the Source Code Form of 203 | the Covered Software, except that You may alter any license notices to 204 | the extent required to remedy known factual inaccuracies. 205 | 206 | 3.5. Application of Additional Terms 207 | 208 | You may choose to offer, and to charge a fee for, warranty, support, 209 | indemnity or liability obligations to one or more recipients of Covered 210 | Software. However, You may do so only on Your own behalf, and not on 211 | behalf of any Contributor. You must make it absolutely clear that any 212 | such warranty, support, indemnity, or liability obligation is offered by 213 | You alone, and You hereby agree to indemnify every Contributor for any 214 | liability incurred by such Contributor as a result of warranty, support, 215 | indemnity or liability terms You offer. You may include additional 216 | disclaimers of warranty and limitations of liability specific to any 217 | jurisdiction. 218 | 219 | 4. Inability to Comply Due to Statute or Regulation 220 | --------------------------------------------------- 221 | 222 | If it is impossible for You to comply with any of the terms of this 223 | License with respect to some or all of the Covered Software due to 224 | statute, judicial order, or regulation then You must: (a) comply with 225 | the terms of this License to the maximum extent possible; and (b) 226 | describe the limitations and the code they affect. Such description must 227 | be placed in a text file included with all distributions of the Covered 228 | Software under this License. Except to the extent prohibited by statute 229 | or regulation, such description must be sufficiently detailed for a 230 | recipient of ordinary skill to be able to understand it. 231 | 232 | 5. Termination 233 | -------------- 234 | 235 | 5.1. The rights granted under this License will terminate automatically 236 | if You fail to comply with any of its terms. However, if You become 237 | compliant, then the rights granted under this License from a particular 238 | Contributor are reinstated (a) provisionally, unless and until such 239 | Contributor explicitly and finally terminates Your grants, and (b) on an 240 | ongoing basis, if such Contributor fails to notify You of the 241 | non-compliance by some reasonable means prior to 60 days after You have 242 | come back into compliance. Moreover, Your grants from a particular 243 | Contributor are reinstated on an ongoing basis if such Contributor 244 | notifies You of the non-compliance by some reasonable means, this is the 245 | first time You have received notice of non-compliance with this License 246 | from such Contributor, and You become compliant prior to 30 days after 247 | Your receipt of the notice. 248 | 249 | 5.2. If You initiate litigation against any entity by asserting a patent 250 | infringement claim (excluding declaratory judgment actions, 251 | counter-claims, and cross-claims) alleging that a Contributor Version 252 | directly or indirectly infringes any patent, then the rights granted to 253 | You by any and all Contributors for the Covered Software under Section 254 | 2.1 of this License shall terminate. 255 | 256 | 5.3. In the event of termination under Sections 5.1 or 5.2 above, all 257 | end user license agreements (excluding distributors and resellers) which 258 | have been validly granted by You or Your distributors under this License 259 | prior to termination shall survive termination. 260 | 261 | ************************************************************************ 262 | * * 263 | * 6. Disclaimer of Warranty * 264 | * ------------------------- * 265 | * * 266 | * Covered Software is provided under this License on an "as is" * 267 | * basis, without warranty of any kind, either expressed, implied, or * 268 | * statutory, including, without limitation, warranties that the * 269 | * Covered Software is free of defects, merchantable, fit for a * 270 | * particular purpose or non-infringing. The entire risk as to the * 271 | * quality and performance of the Covered Software is with You. * 272 | * Should any Covered Software prove defective in any respect, You * 273 | * (not any Contributor) assume the cost of any necessary servicing, * 274 | * repair, or correction. This disclaimer of warranty constitutes an * 275 | * essential part of this License. No use of any Covered Software is * 276 | * authorized under this License except under this disclaimer. * 277 | * * 278 | ************************************************************************ 279 | 280 | ************************************************************************ 281 | * * 282 | * 7. Limitation of Liability * 283 | * -------------------------- * 284 | * * 285 | * Under no circumstances and under no legal theory, whether tort * 286 | * (including negligence), contract, or otherwise, shall any * 287 | * Contributor, or anyone who distributes Covered Software as * 288 | * permitted above, be liable to You for any direct, indirect, * 289 | * special, incidental, or consequential damages of any character * 290 | * including, without limitation, damages for lost profits, loss of * 291 | * goodwill, work stoppage, computer failure or malfunction, or any * 292 | * and all other commercial damages or losses, even if such party * 293 | * shall have been informed of the possibility of such damages. This * 294 | * limitation of liability shall not apply to liability for death or * 295 | * personal injury resulting from such party's negligence to the * 296 | * extent applicable law prohibits such limitation. Some * 297 | * jurisdictions do not allow the exclusion or limitation of * 298 | * incidental or consequential damages, so this exclusion and * 299 | * limitation may not apply to You. * 300 | * * 301 | ************************************************************************ 302 | 303 | 8. Litigation 304 | ------------- 305 | 306 | Any litigation relating to this License may be brought only in the 307 | courts of a jurisdiction where the defendant maintains its principal 308 | place of business and such litigation shall be governed by laws of that 309 | jurisdiction, without reference to its conflict-of-law provisions. 310 | Nothing in this Section shall prevent a party's ability to bring 311 | cross-claims or counter-claims. 312 | 313 | 9. Miscellaneous 314 | ---------------- 315 | 316 | This License represents the complete agreement concerning the subject 317 | matter hereof. If any provision of this License is held to be 318 | unenforceable, such provision shall be reformed only to the extent 319 | necessary to make it enforceable. Any law or regulation which provides 320 | that the language of a contract shall be construed against the drafter 321 | shall not be used to construe this License against a Contributor. 322 | 323 | 10. Versions of the License 324 | --------------------------- 325 | 326 | 10.1. New Versions 327 | 328 | Mozilla Foundation is the license steward. Except as provided in Section 329 | 10.3, no one other than the license steward has the right to modify or 330 | publish new versions of this License. Each version will be given a 331 | distinguishing version number. 332 | 333 | 10.2. Effect of New Versions 334 | 335 | You may distribute the Covered Software under the terms of the version 336 | of the License under which You originally received the Covered Software, 337 | or under the terms of any subsequent version published by the license 338 | steward. 339 | 340 | 10.3. Modified Versions 341 | 342 | If you create software not governed by this License, and you want to 343 | create a new license for such software, you may create and use a 344 | modified version of this License if you rename the license and remove 345 | any references to the name of the license steward (except to note that 346 | such modified license differs from this License). 347 | 348 | 10.4. Distributing Source Code Form that is Incompatible With Secondary 349 | Licenses 350 | 351 | If You choose to distribute Source Code Form that is Incompatible With 352 | Secondary Licenses under the terms of this version of the License, the 353 | notice described in Exhibit B of this License must be attached. 354 | 355 | Exhibit A - Source Code Form License Notice 356 | ------------------------------------------- 357 | 358 | This Source Code Form is subject to the terms of the Mozilla Public 359 | License, v. 2.0. If a copy of the MPL was not distributed with this 360 | file, You can obtain one at http://mozilla.org/MPL/2.0/. 361 | 362 | If it is not possible or desirable to put the notice in a particular 363 | file, then You may include the notice in a location (such as a LICENSE 364 | file in a relevant directory) where a recipient would be likely to look 365 | for such a notice. 366 | 367 | You may add additional accurate notices of copyright ownership. 368 | 369 | Exhibit B - "Incompatible With Secondary Licenses" Notice 370 | --------------------------------------------------------- 371 | 372 | This Source Code Form is "Incompatible With Secondary Licenses", as 373 | defined by the Mozilla Public License, v. 2.0. 374 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # transductio 2 | 3 | 4 | 5 | [![clojars badge](https://badgen.net/badge/release/1.1.0/blue)](https://clojars.org/systems.thoughtfull/transductio/versions/1.1.0) [![cljdoc badge](https://badgen.net/badge/docs/1.1.0/blue)](https://cljdoc.org/d/systems.thoughtfull/transductio/1.1.0/doc/readme) 6 | 7 | A bridge from I/O to transducers, and back! 8 | 9 | This library provides two core functions to bridge I/O with transducers, and convenience functions 10 | building on them. `decoder` creates a function that can produce data from input for use with 11 | transducers and `encoder` makes a function that takes data, possibly through a transducer, and 12 | writes it to output. 13 | 14 | `decoder` is analogous to a source collection in a transduction pipeline. `encoder` is analogous to 15 | `into`, it is a transduction context that takes a transducer and an input collection, but writes to 16 | output instead of building a collection. 17 | 18 | `decoder` takes four arguments: open, decode, done?, close. It returns a function that takes a 19 | source and returns a reducible. This reducible calls open with the source, then decode with that 20 | result, and eventually, when done? returns true, the reduction completes and it calls close. 21 | 22 | For example, if you want to decode Clojure data: 23 | 24 | ```clojure 25 | (def clojure-decoder 26 | (decoder (comp PushbackReader/new io/reader) 27 | #(read % false ::eof) 28 | #{::eof} 29 | AutoCloseable/.close)) 30 | 31 | (into [] (clojure-decoder (StringReader. "1 2 3"))) 32 | ;;=> [1 2 3] 33 | ``` 34 | 35 | `encoder` takes three arguments: open, encode!, close. It returns a function that acts like `into`. 36 | Like `into` it has two arities. The first takes a sink and a source and reduces the source into the 37 | sink. It calls open with the sink, then encode! with that result and each value from the source, 38 | and eventually, when it exhausts the source, the reduction completes and it calls close. 39 | 40 | The second arity takes a sink, a transduction, and a source. The process is the same as above, but 41 | the data flows from the source, through the transduction, then into the sink. 42 | 43 | For example, if you want to encode Clojure data: 44 | 45 | ```clojure 46 | (def clojure-encoder 47 | (encoder io/writer 48 | (fn [^Writer out value] (.write out (prn-str value))) 49 | AutoCloseable/.close)) 50 | 51 | (clojure-encoder "/tmp/foo.clj" (map inc) [1 2 3]) 52 | 53 | (slurp "/tmp/foo.clj") 54 | ;;=> "2\n3\n4\n" 55 | ``` 56 | 57 | ## Comparison to `clojure.core/iteration` 58 | 59 | Unlike `clojure.core/iteration`, a decoder repeatedly calls `decode` with the return value from 60 | `open`. `open` should return a stateful, mutable object that produces a new value every time it is 61 | given to `decode`, there is no succession of continuation tokens. This is simpler to think about 62 | and use in common situations like `java.io` streams and readers. 63 | 64 | A decoder also cleans up resources when its reduction completes (early or otherwise). This makes it 65 | suitable for working with things like database connection, file descriptors, etc. If an error 66 | occurs during the reduction, or if the reduction returns early (i.e. someone returns a `reduced`), 67 | there is still an opportunity to release resources when the decoder calls `close`. 68 | 69 | ## Clojure and EDN data 70 | 71 | There are three functions for decoding/encoding Clojure and EDN data. 72 | 73 | `clojure-decoder` decodes Clojure data. It takes `:encoding` which it sends to 74 | `clojure.java.io/reader`, `:features` and `:read-cond` as options which it passes along to 75 | `clojure.core/read`, and `:data-readers`, `:default-data-reader-fn`, and `:read-eval` which it binds 76 | to the appropriate dynamic variables for the duration of the reduction/transduction. 77 | 78 | `clojure-encoder` encodes Clojure data. It takes `:encoding` and `:append` as options which it 79 | passes along to `clojure.java.io/writer`. It encodes Clojure data using `prn-str`. 80 | 81 | `edn-decoder` decodes EDN data. It takes `:encoding` which it sends to `clojure.java.io./reader` 82 | and `:features` and `:read-cond` as options which it passes along to `clojure.edn/read`. 83 | 84 | There is no EDN encoder, because there isn't really such a thing in Clojure. `clojure-encoder` can 85 | substitute, but EDN is probably best hand written because `prn-str` isn't necessarily guaranteed to 86 | produce valid EDN data.[^1] 87 | 88 | [^1]: See https://nitor.com/en/articles/pitfalls-and-bumps-clojures-extensible-data-notation-edn 89 | 90 | ## License 91 | 92 | > Copyright © technosophist 93 | > 94 | > This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of 95 | > the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 96 | > 97 | > This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public 98 | > License, v. 2.0. 99 | -------------------------------------------------------------------------------- /build.edn: -------------------------------------------------------------------------------- 1 | {:description "A bridge from I/O to transducers and back" 2 | :lib systems.thoughtfull/transductio 3 | :version "1.1.0"} 4 | -------------------------------------------------------------------------------- /deps.edn: -------------------------------------------------------------------------------- 1 | {:aliases {:build {:deps {systems.thoughtfull/build {:mvn/version "0.5.0"}} 2 | :ns-default systems.thoughtfull.build} 3 | :test {:exec-fn cognitect.test-runner.api/test 4 | :extra-deps {io.github.cognitect-labs/test-runner 5 | {:git/tag "v0.5.1" :git/sha "dfb30dd"}} 6 | :extra-paths ["test"]}} 7 | :deps {org.clojure/clojure {:mvn/version "1.12.0"}} 8 | :paths ["src"]} 9 | -------------------------------------------------------------------------------- /img/transductio-logo-1024.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/thoughtfull-clojure/transductio/20f692638b890732fe5d263b74ad62a86ffa0a81/img/transductio-logo-1024.png -------------------------------------------------------------------------------- /img/transductio-logo-150.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/thoughtfull-clojure/transductio/20f692638b890732fe5d263b74ad62a86ffa0a81/img/transductio-logo-150.png -------------------------------------------------------------------------------- /img/transductio-logo-300.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/thoughtfull-clojure/transductio/20f692638b890732fe5d263b74ad62a86ffa0a81/img/transductio-logo-300.png -------------------------------------------------------------------------------- /img/transductio-logo.svg: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 91 | -------------------------------------------------------------------------------- /src/systems/thoughtfull/transductio.clj: -------------------------------------------------------------------------------- 1 | ;; Copyright © technosophist 2 | ;; 3 | ;; This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of 4 | ;; the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 5 | ;; 6 | ;; This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public 7 | ;; License, v. 2.0. 8 | (ns systems.thoughtfull.transductio 9 | (:require 10 | [clojure.edn :as edn] 11 | [clojure.java.io :as io]) 12 | (:import 13 | (clojure.lang IReduceInit) 14 | (java.io OutputStream PushbackReader Writer) 15 | (java.lang AutoCloseable))) 16 | 17 | (set! *warn-on-reflection* true) 18 | (set! *unchecked-math* :warn-on-boxed) 19 | 20 | (defn decoder 21 | "Returns a function that takes a source and returns a reducible that, opens the source, repeatedly 22 | decodes data from it, and closes it when it is done. 23 | 24 | open takes the source and returns a stateful, mutable object that will be given to decode and 25 | eventually to close. 26 | 27 | decode is given the opened source and must return either a decoded value or a sentinel 28 | indicating there is no more data. 29 | 30 | done? is given each decoded value and if it returns truthy, then the decoding ends. 31 | 32 | When the reduction completes whether normally, early (someone returns a reduced), or because of 33 | an exception, then close is called. 34 | 35 | If close is not given, then it defaults to java.lang.AutoCloseable/.close. 36 | 37 | See stream-decoder and reader-decoder." 38 | ([open decode done?] 39 | (decoder open decode done? nil)) 40 | ([open decode done? close] 41 | (fn [source] 42 | (let [close (or close AutoCloseable/.close)] 43 | (reify 44 | IReduceInit 45 | (reduce 46 | [_ rf init] 47 | (let [in (open source)] 48 | (try 49 | (loop [acc init 50 | v (decode in)] 51 | (if (done? v) 52 | acc 53 | (let [acc (rf acc v)] 54 | (if (reduced? acc) 55 | @acc 56 | (recur acc (decode in)))))) 57 | (finally 58 | (close in)))))))))) 59 | 60 | (defn stream-decoder 61 | "Returns a function that takes a source and returns a reducible that, opens the source as a 62 | java.io.InputStream, repeatedly decodes data from it, and closes it when it is done. 63 | 64 | The decoder opens the source with clojure.java.io/input-stream. 65 | 66 | decode is given the opened source and must return either a decoded value or a sentinel 67 | indicating there is no more data. 68 | 69 | done? is given each decoded value and if it returns truthy, then the decoding ends. 70 | 71 | The decoder closes the source with java.lang.AutoCloseable/.close. 72 | 73 | See decoder, clojure-decoder, edn-decoder, and reader-decoder." 74 | [decode done?] 75 | (decoder io/input-stream decode done?)) 76 | 77 | (defn reader-decoder 78 | "Returns a function that takes a source and returns a reducible that, opens the source as a 79 | java.io.Reader, repeatedly decodes data from it, and closes it when it is done. 80 | 81 | The decoder opens the source with clojure.java.io/reader. If encoding is given, then it is 82 | passed along to clojure.java.io/reader. 83 | 84 | decode is given the opened source and must return either a decoded value or a sentinel 85 | indicating there is no more data. 86 | 87 | done? is given each decoded value and if it returns truthy, then the decoding ends. 88 | 89 | The decoder closes the source with java.lang.AutoCloseable/.close. 90 | 91 | See decoder, clojure-decoder, edn-decoder, and stream-decoder." 92 | ([decode done?] 93 | (decoder io/reader decode done?)) 94 | ([decode done? encoding] 95 | (decoder #(io/reader % :encoding encoding) decode done?))) 96 | 97 | (defn- pushback-reader 98 | [encoding] 99 | (fn [source] 100 | (if (instance? PushbackReader source) 101 | source 102 | (PushbackReader. (io/reader source :encoding encoding))))) 103 | 104 | (defn clojure-decoder 105 | "Returns a function that takes a source and returns a reducible that, opens the source as a 106 | java.io.PushbackReader, repeatedly decodes Clojure data from it, and closes it when it is done. 107 | 108 | The decoder opens the source as a java.io.PushbackReader. If the source is already a 109 | PushbackReader, then it is used without modification. If it is not a PushbackReader, then it is 110 | given to clojure.java.io/reader with the encoding (if specified) and then wrapped in a 111 | PushbackReader. 112 | 113 | If features or read-cond are specified, they are given as options to clojure.core/read. 114 | 115 | If data-readers, default-data-readers-fn, or read-eval are given they are bound to 116 | *data-readers*, *default-data-reader-fn*, and *read-eval* (respectively) for the duration of the 117 | reduction/transduction. 118 | 119 | See decoder, edn-decoder, reader-decoder, and stream-decoder." 120 | [& {:keys [data-readers default-data-reader-fn encoding features read-cond read-eval]}] 121 | (let [eof (Object.) 122 | opts (merge {:eof eof} 123 | (when (some? features) 124 | {:features features}) 125 | (when (some? read-cond) 126 | {:read-cond read-cond})) 127 | bindings (merge {} 128 | (when (some? data-readers) 129 | {#'*data-readers* data-readers}) 130 | (when (some? default-data-reader-fn) 131 | {#'*default-data-reader-fn* default-data-reader-fn}) 132 | (when (some? read-eval) 133 | {#'*read-eval* read-eval})) 134 | decoder* (decoder (pushback-reader encoding) #(read opts %) #{eof})] 135 | (fn [source] 136 | (reify IReduceInit 137 | (reduce [_ rf init] 138 | (with-bindings bindings 139 | (.reduce ^IReduceInit (decoder* source) rf init))))))) 140 | 141 | (defn edn-decoder 142 | "Returns a function that takes a source and returns a reducible that, opens the source as a 143 | java.io.PushbackReader, repeatedly decodes EDN data from it, and closes it when it is done. 144 | 145 | The decoder opens the source as a java.io.PushbackReader. If the source is already a 146 | PushbackReader, then it is used without modification. If it is not a PushbackReader, then it is 147 | given to clojure.java.io/reader with the encoding (if specified) and then wrapped in a 148 | PushbackReader. 149 | 150 | If default or readers are specified, they are given as options to clojure.edn/read. 151 | 152 | See decoder, clojure-decoder, reader-decoder, and stream-decoder." 153 | [& {:keys [default encoding readers]}] 154 | (let [eof (Object.) 155 | opts (merge {:eof eof} 156 | (when (some? default) 157 | {:default default}) 158 | (when (some? readers) 159 | {:readers readers}))] 160 | (decoder (pushback-reader encoding) 161 | #(edn/read opts %) 162 | #{eof}))) 163 | 164 | (defn encoder 165 | "Returns a function that takes either a sink and a source, reducing the source into the sink, or a 166 | sink, a transducer, and a source, transducing the source into the sink through the transducer. 167 | This is an analog of into but for a mutable sink. 168 | 169 | open takes the sink and returns a stateful, mutable object that will be given to encode! and 170 | eventually to close. 171 | 172 | encode! is given the opened sink and a value and must mutate the sink with the value. The 173 | return value from encode! is ignored. 174 | 175 | When the reduction/transduction completes whether normally, early (someone returns a reduced), 176 | or because of an exception, then close is called. 177 | 178 | If close is not given, then it defaults to java.lang.AutoCloseable/.close. 179 | 180 | See clojure-encoder, stream-encoder, and writer-encoder" 181 | ([open encode!] 182 | (encoder open encode! nil)) 183 | ([open encode! close] 184 | (fn 185 | ([sink source] 186 | (let [out (open sink) 187 | close (or close AutoCloseable/.close)] 188 | (try 189 | (reduce (fn [out value] (encode! out value) out) out source) 190 | nil 191 | (finally 192 | (close out))))) 193 | ([sink xf source] 194 | (let [out (open sink) 195 | close (or close AutoCloseable/.close)] 196 | (try 197 | (transduce xf (fn ([out] out) ([out value] (encode! out value) out)) out source) 198 | nil 199 | (finally 200 | (close out)))))))) 201 | 202 | (defn stream-encoder 203 | "Returns a function that takes either a sink and a source, reducing the source into the sink, or a 204 | sink, a transducer, and a source, transducing the source into the sink through the transducer. 205 | This is an analog of into but for a java.io.OutputStream. 206 | 207 | The encoder opens the sink with clojure.java.io/output-stream. If append is given, then it is 208 | passed along to clojure.java.io/output-stream. 209 | 210 | The source (or the transducer applied to the source) must return byte arrays which are written 211 | to the output stream. 212 | 213 | When the reduction/transduction completes whether normally, early (someone returns a reduced), 214 | or because of an exception, then the stream is closed. 215 | 216 | See encoder, clojure-encoder, and writer-encoder" 217 | ([] 218 | (encoder io/output-stream ^[bytes] OutputStream/.write)) 219 | ([append] 220 | (encoder #(io/output-stream % :append append) ^[bytes] OutputStream/.write))) 221 | 222 | (defn writer-encoder 223 | "Returns a function that takes either a sink and a source, reducing the source into the sink, or a 224 | sink, a transducer, and a source, transducing the source into the sink through the transducer. 225 | This is an analog of into but for a java.io.Writer. 226 | 227 | The encoder opens the sink with clojure.java.io/writer. If append is given, then it is passed 228 | along to clojure.java.io/writer. 229 | 230 | The source (or the transducer applied to the source) must return Strings which are written to 231 | the output stream. 232 | 233 | When the reduction/transduction completes whether normally, early (someone returns a reduced), 234 | or because of an exception, then the stream is closed. 235 | 236 | See encoder, clojure-encoder, and stream-encoder" 237 | ([] 238 | (encoder io/writer ^[String] Writer/.write)) 239 | ([append] 240 | (encoder #(io/writer % :append append) ^[String] Writer/.write))) 241 | 242 | (defn clojure-encoder 243 | "Returns a function that takes either a sink and a source, reducing the source as Clojure data 244 | into the sink, or a sink, a transducer, and a source, transducing the source as Clojure data 245 | into the sink through the transducer. This is an analog of into but for Clojure data into a 246 | java.io.Writer. 247 | 248 | The encoder opens the sink with clojure.java.io/writer. If encoding or append are given, then 249 | they are passed along to clojure.java.io/writer. 250 | 251 | The data from the source (or the transducer applied to the source) is written to the sink using 252 | prn-str. 253 | 254 | When the reduction/transduction completes whether normally, early (someone returns a reduced), 255 | or because of an exception, then the stream is closed. 256 | 257 | See encoder, stream-encoder, and writer-encoder" 258 | [& {:keys [encoding append]}] 259 | (encoder #(io/writer % :encoding encoding :append append) 260 | (fn [^Writer sink value] 261 | (.write sink (prn-str value))))) 262 | -------------------------------------------------------------------------------- /test/systems/thoughtfull/transductio_test.clj: -------------------------------------------------------------------------------- 1 | ;; Copyright © technosophist 2 | ;; 3 | ;; This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of 4 | ;; the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 5 | ;; 6 | ;; This Source Code Form is "Incompatible With Secondary Licenses", as defined by the Mozilla Public 7 | ;; License, v. 2.0. 8 | (ns systems.thoughtfull.transductio-test 9 | (:require 10 | [clojure.test :refer [deftest is]] 11 | [systems.thoughtfull.transductio :refer [clojure-decoder clojure-encoder decoder edn-decoder 12 | reader-decoder stream-decoder stream-encoder encoder 13 | writer-encoder]]) 14 | (:import 15 | (java.io ByteArrayInputStream ByteArrayOutputStream File InputStream PushbackReader Reader 16 | StringReader StringWriter))) 17 | 18 | (defn close-fn 19 | [closed?] 20 | (fn [_] (deliver closed? true))) 21 | 22 | (defn test-decoder 23 | ([] 24 | (test-decoder #(read % false ::eof))) 25 | ([decode] 26 | (let [closed? (promise)] 27 | [closed? (decoder (comp PushbackReader/new StringReader/new) decode #{::eof} 28 | (close-fn closed?))]))) 29 | 30 | (deftest t-decoder-closes 31 | (let [[closed? decoder] (test-decoder)] 32 | (is (= [1 2 3] (into [] (decoder "1 2 3")))) 33 | (is (deref closed? 1000 false)))) 34 | 35 | (deftest t-decoder-closes-with-reduced 36 | (let [[closed? decoder] (test-decoder)] 37 | (is (= [1] (into [] (take 1) (decoder "1 2 3")))) 38 | (is (deref closed? 1000 false)))) 39 | 40 | (deftest t-decoder-closes-with-exception 41 | (let [[closed? decoder] (test-decoder (fn [_] (throw (Exception.))))] 42 | (try 43 | (into [] (take 1) (decoder "1 2 3")) 44 | (catch Exception _)) 45 | (is (deref closed? 1000 false)))) 46 | 47 | (deftest t-stream-decoder 48 | (is (= [102 111 111] 49 | (into [] ((stream-decoder InputStream/.read #{-1}) 50 | (ByteArrayInputStream. (.getBytes "foo"))))))) 51 | 52 | (deftest t-reader-decoder 53 | (is (= [102 111 111] 54 | (into [] ((reader-decoder Reader/.read #{-1}) 55 | (ByteArrayInputStream. (.getBytes "foo"))))))) 56 | 57 | (deftest t-reader-decoder-uses-encoding 58 | (is (= [8220] 59 | (into [] ((reader-decoder Reader/.read #{-1} "windows-1252") 60 | (ByteArrayInputStream. (byte-array [147]))))))) 61 | 62 | (deftest t-clojure-decoder 63 | (is (= [1 2 3] (into [] ((clojure-decoder) (StringReader. "1\n2\n3\n")))))) 64 | 65 | (deftest t-clojure-decoder-uses-features 66 | (is (= [] (into [] ((clojure-decoder :read-cond :allow) (StringReader. "#?(:blah \"blah\")"))))) 67 | (is (= ["blah"] 68 | (into [] ((clojure-decoder :read-cond :allow :features #{:blah}) 69 | (StringReader. "#?(:blah \"blah\")")))))) 70 | 71 | (deftest t-clojure-decoder-uses-read-cond 72 | (is (= [(reader-conditional '(:clj "clj" :cljs "cljs") false)] 73 | (into [] ((clojure-decoder :read-cond :preserve) 74 | (StringReader. "#?(:clj \"clj\" :cljs \"cljs\")"))))) 75 | (is (thrown-with-msg? RuntimeException 76 | #"^Conditional read not allowed$" 77 | (into [] ((clojure-decoder :read-cond false) 78 | (StringReader. "#?(:clj \"clj\" :cljs \"cljs\")")))))) 79 | 80 | (deftest t-clojure-decoder-uses-encoding 81 | (is (= ["“"] 82 | (into [] ((clojure-decoder :encoding "windows-1252") 83 | (ByteArrayInputStream. (byte-array [34 147 34]))))))) 84 | 85 | (defn foo [val] val) 86 | 87 | (deftest t-clojure-decoder-binds-data-readers 88 | (is (= [[1 2 3]] 89 | (into [] ((clojure-decoder :data-readers {'foo #'systems.thoughtfull.transductio-test/foo}) 90 | (StringReader. "#foo [1 2 3]")))))) 91 | 92 | (deftest t-clojure-decoder-binds-default-data-reader-fn 93 | (is (= [:blah] 94 | (into [] ((clojure-decoder :default-data-reader-fn (fn [_ _] :blah)) 95 | (StringReader. "#foo [1 2 3]")))))) 96 | 97 | (deftest t-clojure-decoder-binds-read-eval 98 | (is (= [42] (into [] ((clojure-decoder :read-eval true) (StringReader. "#=(* 21 2)"))))) 99 | (is (thrown-with-msg? RuntimeException 100 | #"^EvalReader not allowed when \*read-eval\* is false.$" 101 | (into [] ((clojure-decoder :read-eval false) 102 | (StringReader. "#=(* 21 2)")))))) 103 | 104 | (deftest t-edn-decoder 105 | (is (= [1 2 3] (into [] ((edn-decoder) (StringReader. "1\n2\n3\n")))))) 106 | 107 | (deftest t-edn-decoder-uses-default 108 | (is (= [:blah] 109 | (into [] ((edn-decoder :default (fn [_ _] :blah)) (StringReader. "#foo [1 2 3]")))))) 110 | 111 | (deftest t-edn-decoder-uses-readers 112 | (is (= [[1 2 3]] 113 | (into [] ((edn-decoder :readers {'foo #'systems.thoughtfull.transductio-test/foo}) 114 | (StringReader. "#foo [1 2 3]")))))) 115 | 116 | (deftest t-edn-decoder-uses-encoding 117 | (is (= ["“"] 118 | (into [] ((edn-decoder :encoding "windows-1252") 119 | (ByteArrayInputStream. (byte-array [34 147 34]))))))) 120 | 121 | (defn test-encoder 122 | ([] 123 | (test-encoder #(.write %1 (prn-str %2)))) 124 | ([encode!] 125 | (let [closed? (promise)] 126 | [closed? (encoder identity encode! (close-fn closed?))]))) 127 | 128 | (deftest t-encoder-closes 129 | (let [out (StringWriter.) 130 | [closed? encoder] (test-encoder)] 131 | (encoder out [1 2 3]) 132 | (is (= "1\n2\n3\n" (.toString out))) 133 | (is (deref closed? 1000 false)))) 134 | 135 | (deftest t-encoder-closes-with-reduced 136 | (let [out (StringWriter.) 137 | [closed? encoder] (test-encoder)] 138 | (encoder out (take 1) [1 2 3]) 139 | (is (= "1\n" (.toString out))) 140 | (is (deref closed? 1000 false)))) 141 | 142 | (deftest t-encoder-closes-with-exception 143 | (let [out (StringWriter.) 144 | [closed? encoder] (test-encoder (fn [_ _] (throw (Exception.))))] 145 | (try 146 | (encoder out [1 2 3]) 147 | (catch Exception _)) 148 | (is (= "" (.toString out))) 149 | (is (deref closed? 1000 false)))) 150 | 151 | (deftest t-stream-encoder 152 | (let [out (ByteArrayOutputStream.)] 153 | ((stream-encoder) out [(.getBytes "foo")]) 154 | (is (= [102 111 111] (seq (.toByteArray out)))))) 155 | 156 | (deftest t-stream-encoder-uses-append 157 | (let [out (File/createTempFile "transductio-" nil)] 158 | ((stream-encoder true) out [(.getBytes "foo")]) 159 | ((stream-encoder true) out [(.getBytes "foo")]) 160 | (is (= "foofoo" (slurp out))))) 161 | 162 | (deftest t-writer-encoder 163 | (let [out (StringWriter.)] 164 | ((writer-encoder) out ["foo"]) 165 | (is (= "foo" (.toString out))))) 166 | 167 | (deftest t-writer-encoder-uses-append 168 | (let [out (File/createTempFile "transductio-" nil)] 169 | ((writer-encoder true) out ["foo"]) 170 | ((writer-encoder true) out ["foo"]) 171 | (is (= "foofoo" (slurp out))))) 172 | 173 | (deftest t-clojure-encoder 174 | (let [out (StringWriter.)] 175 | (is (empty? (into [] ((clojure-encoder) out [1 2 3])))) 176 | (is (= "1\n2\n3\n" (.toString out))))) 177 | 178 | (deftest t-clojure-encoder-uses-encoding 179 | (let [out (ByteArrayOutputStream.)] 180 | ((clojure-encoder :encoding "windows-1252") out ["“"]) 181 | (is (= "\"“\"\n" (String. (.toByteArray out) "windows-1252"))))) 182 | 183 | (deftest t-clojure-encoder-uses-append 184 | (let [out (File/createTempFile "transductio-" nil)] 185 | ((clojure-encoder :append true) out ["a"]) 186 | ((clojure-encoder :append true) out ["b"]) 187 | (is (= "\"a\"\n\"b\"\n" (slurp out))))) 188 | --------------------------------------------------------------------------------