1<!-- 2 Licensed to the Apache Software Foundation (ASF) under one or more 3 contributor license agreements. See the NOTICE file distributed with 4 this work for additional information regarding copyright ownership. 5 The ASF licenses this file to You under the Apache License, Version 2.0 6 the "License"); you may not use this file except in compliance with 7 the License. You may obtain a copy of the License at 8 9 http://www.apache.org/licenses/LICENSE-2.0 10 11 Unless required by applicable law or agreed to in writing, software 12 distributed under the License is distributed on an "AS IS" BASIS, 13 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 See the License for the specific language governing permissions and 15 limitations under the License. 16 --> 17 18# Contributing to Lucene Guide 19 20## Working with Code 21 22### Getting the source code 23 24First of all, you need the Lucene source code. 25 26Get the source code using: `git clone https://github.com/apache/lucene` 27 28### Notes for required Java version 29 30Be sure that you are using an appropriate version of the JDK. Please check [README](./README.md) for the required JDK version for current main branch. 31 32### Building with Gradle 33 34Lucene uses [Gradle](https://gradle.org/) for build control. Gradle is itself Java-based and may be incompatible with newer Java versions; you can still build and test Lucene with these Java releases, see [jvms.txt](./help/jvms.txt) for more information. 35 36NOTE: DO NOT use the `gradle` command that is perhaps installed on your machine. This may result in using a different gradle version than the project requires and this is known to lead to very cryptic errors. The "gradle wrapper" (gradlew script) does everything required to build the project from scratch: it downloads the correct version of gradle, sets up sane local configurations and is tested on multiple environments. 37 38The first time you run gradlew, it will create a file "gradle.properties" that contains machine-specific settings. Normally you can use this file as-is, but it can be modified if necessary. 39 40Type `./gradlew helpWorkflow` to show typical workflow tasks ([help/workflow.txt](./help/workflow.txt)). 41 42Also run `./gradlew help`, this will print a list of help guides that introduce and explain 43various parts of the build system, including typical workflow tasks. 44 45### Code formatting and checks 46 47If you've modified any sources, run `./gradlew tidy` to apply code formatting conventions automatically (see [help/formatting.txt](https://github.com/apache/lucene/blob/main/help/formatting.txt)). 48 49Please make sure that all unit tests and validations succeed before constructing your patch: `./gradlew check`. This will assemble Lucene and run all validation tasks (including tests). There are various commands to check the code; type `./gradlew helpTest` for more information ([help/tests.txt](./help/tests.txt)). 50 51In case your contribution fixes a bug, please create a new test case that fails before your fix, to show the presence of the bug and ensure it never re-occurs. A test case showing the presence of a bug is also a good contribution by itself. 52 53### IDE support 54 55- *IntelliJ* - IntelliJ idea can import and build gradle-based projects out of the box. 56- *Eclipse* - Basic support ([help/IDEs.txt](https://github.com/apache/lucene/blob/main/help/IDEs.txt#L7)). 57- *Netbeans* - Not tested. 58 59## Benchmarking 60 61Use the tool suite at [luceneutil](https://github.com/mikemccand/luceneutil) to benchmark your code changes 62if you think that your change may have measurably changed the performance of a task. Apache Lucene also contains an off the shelf benchmark [module](https://github.com/apache/lucene/tree/main/lucene/benchmark). 63 64This is the same suite that is run in the [nightly benchmarks](https://home.apache.org/~mikemccand/lucenebench/). 65 66The instructions for running the benchmarks can be found in the luceneutil [README](https://github.com/mikemccand/luceneutil/blob/master/README.md). 67 68The Lucene community is also interested in other implementations of these benchmark tasks. 69Feel free to share your findings (especially if your implementation performs better!) through the [Lucene mailing lists](https://lucene.apache.org/core/discussion.html) or open [PRs](https://github.com/mikemccand/luceneutil/pulls), [issues](https://github.com/mikemccand/luceneutil/issues) on the luceneutil project directly. 70 71## Contributing your work 72 73You have two options to contribute your work: you can either create a patch and attach it to an issue on [Jira](https://issues.apache.org/jira/browse/LUCENE), or open a pull request at https://github.com/apache/lucene - whichever works best for you. 74 75Please be patient. Committers are busy people too. If no one responds to your patch after a few days, please make friendly reminders. Please incorporate others' suggestions into into your patch if you think they're reasonable. Finally, remember that even a patch that is not committed is useful to the community. 76 77### Opening a pull request 78 79Please refer to [GitHub's documentation](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests) for an explanation of how to create a pull request. 80 81You should open a pull request against the `main` branch. Committers will backport it to the maintenance branches once the change is merged into `main` (as far as it is possible). 82 83You can open a pull request with or without Jira issue. If there is an associated Jira issue, the pull request title should start with the Jira issue number that your work is related to, this way your pull request will get automatically linked from the Jira issue. 84 85 86### Creating a patch 87 88Note that you do not need to create a patch if you already opened a pull request on GitHub. 89 90Patches should be attached to an issue in [Apache Jira](https://issues.apache.org/jira/projects/LUCENE/issues/), so first you'll need to create an account for it (if you don't have one). 91 92Please refer to [git diff documentation](https://git-scm.com/docs/git-diff) for information of how to create a patch. 93 94Before creating your patch, you may want to get 'main' up to date with the latest from upstream. This will help avoid the possibility of others finding merge conflicts when applying your patch. This can be done with git pull if main is the current branch. 95 96### Add a CHANGES entry 97 98You may want to add a CHANGES entry to [CHANGES.txt](./lucene/CHANGES.txt). A CHANGES entry should start with the Jira issue key `LUCENE-XXXXX` or pull request number `GITHUB#XXX` that is followed by the description of the change and contributors' name. Please see the existing entries for reference. 99 100## Stay involved 101 102Contributors should join the [Lucene mailing lists](https://lucene.apache.org/core/discussion.html). In particular, the commit list (to see changes as they are made), the dev list (to join discussions of changes) and the user list (to help others). 103 104Please keep discussions about Lucene on list so that everyone benefits. Emailing individual committers with questions about specific Lucene issues is discouraged. See http://people.apache.org/~hossman/#private_q. 105 106## Getting your feet wet: where to begin? 107 108New to Lucene? Want to find JIRA issues that you can work on without taking on the whole world? 109 110The Lucene/Solr developers use the "newdev" label to mark issues that developers new to Lucene might be interested in working on. The rough criteria used to make this selection are: 111 112- Nobody has done any work on the issue yet. 113- The issue is likely not controversial. 114- The issue is likely self-contained with limited scope. 115 116To see a list of open Lucene issues with the newdev label, look at this link [http://s.apache.org/newdevlucenesolr](https://issues.apache.org/jira/browse/SOLR-15591?jql=(project%3DLUCENE)%20AND%20resolution%3DUnresolved%20AND%20labels%3Dnewdev). 117 118## Developer tips 119 120For more contribution guidelines and tips, see [DeveloperTips](https://cwiki.apache.org/confluence/display/LUCENE/DeveloperTips). 121