# Contribution Guide TiDB is a community driven open source project and we welcome any contributor. The process of contributing to the TiDB project may be different than many other projects you have been involved in. This document outlines some conventions about development workflow, commit message formatting, contact points and other resources to make it easier to get your contribution accepted. This document is the canonical source of truth for things like supported toolchain versions for building and testing TiDB. ## Pre submit pull request/issue flight checks Before you move on, please make sure what your issue and/or pull request is, a simple bug fix or an architecture change. In order to save reviewers' time, each issue should be filed with template and should be sanity-checkable in under 5 minutes. ### Is this a simple bug fix? Bug fixes usually come with tests. With the help of continuous integration test, patches can be easy to review. Please update the unit tests so that they catch the bug! Please check example [here](https://github.com/pingcap/tidb/pull/2808). ### Is this an architecture improvement? Some examples of "Architecture" improvements: - Converting structs to interfaces. - Improving test coverage. - Decoupling logic or creation of new utilities. - Making code more resilient (sleeps, backoffs, reducing flakiness, etc). If you are improving the quality of code, then justify/state exactly what you are 'cleaning up' in your Pull Request so as to save reviewers' time. An example will be this [pull request](https://github.com/pingcap/tidb/pull/3113). If you're making code more resilient, test it locally to demonstrate how exactly your patch changes things. ## Building TiDB on a local OS/shell environment TiDB development only requires `go` set-up. If you already have, simply type `make` from terminal. ### Go TiDB is written in [Go](http://golang.org). If you don't have a Go development environment, please [set one up](http://golang.org/doc/code.html). The version of GO should be **1.8.1** or above. After installation, you'll need `GOPATH` defined, and `PATH` modified to access your Go binaries. A common setup is the following but you could always google a setup for your own flavor. ```sh export GOPATH=$HOME/go export PATH=$PATH:$GOPATH/bin ``` #### Dependency management TiDB build/test scripts use [`glide`](https://github.com/Masterminds/glide) to manage dependencies. ```sh go get -u github.com/Masterminds/glide ``` ## Workflow ### Step 1: Fork in the cloud 1. Visit https://github.com/pingcap/tidb 2. Click `Fork` button (top right) to establish a cloud-based fork. ### Step 2: Clone fork to local storage Per Go's [workspace instructions][go-workspace], place TiDB's code on your `GOPATH` using the following cloning procedure. Define a local working directory: ```sh # If your GOPATH has multiple paths, pick # just one and use it instead of $GOPATH here working_dir=$GOPATH/src/github.com/pingcap ``` > If you already worked with Go development on github before, the `pingcap` directory > will be a sibling to your existing `github.com` directory. Set `user` to match your github profile name: ```sh user={your github profile name} ``` Create your clone: ```sh mkdir -p $working_dir cd $working_dir git clone https://github.com/$user/tidb.git # the following is recommended # or: git clone git@github.com:$user/tidb.git cd $working_dir/tidb git remote add upstream https://github.com/pingcap/tidb.git # or: git remote add upstream git@github.com:pingcap/tidb.git # Never push to upstream master since you do not have write access git remote set-url --push upstream no_push # Confirm that your remotes make sense: # It should look like: # origin git@github.com:$(user)/tidb.git (fetch) # origin git@github.com:$(user)/tidb.git (push) # upstream https://github.com/pingcap/tidb (fetch) # upstream no_push (push) git remote -v ``` #### Define a pre-commit hook Please link the TiDB pre-commit hook into your `.git` directory. This hook checks your commits for formatting, building, doc generation, etc. ```sh cd $working_dir/tidb/.git/hooks ln -s ../../hooks/pre-commit . ``` Sometime, pre-commit hook can not be executable. In such case, you have to make it executable manually. ```sh chmod +x hooks/pre-commit ``` ### Step 3: Branch Get your local master up to date: ```sh cd $working_dir/tidb git fetch upstream git checkout master git rebase upstream/master ``` Branch from master: ```sh git checkout -b myfeature ``` Then edit code on the `myfeature` branch. #### Build ```sh # Run unit test to make sure all test passed make dev # Build tidb-server to make sure a binary can be built cd $working_dir/tidb make # Check checklist before you move on make checklist ``` ### Step 4: Keep your branch in sync ```sh # While on your myfeature branch git fetch upstream git rebase upstream/master ``` ### Step 5: Commit Commit your changes. ```sh git commit ``` Likely you'll go back and edit/build/test some more than `commit --amend` in a few cycles. ### Step 6: Push When ready to review (or just to establish an offsite backup or your work), push your branch to your fork on `github.com`: ```sh git push -f origin myfeature ``` ### Step 7: Create a pull request 1. Visit your fork at https://github.com/$user/tidb (replace `$user` obviously). 2. Click the `Compare & pull request` button next to your `myfeature` branch. #### Step 8: get a code review Once your pull request has been opened, it will be assigned to at least two reviewers. Those reviewers will do a thorough code review, looking for correctness, bugs, opportunities for improvement, documentation and comments, and style. Commit changes made in response to review comments to the same branch on your fork. Very small PRs are easy to review. Very large PRs are very difficult to review. ## Code style The coding style suggested by the Golang community is used in TiDB. See the [style doc](https://github.com/golang/go/wiki/CodeReviewComments) for details. ## Commit message style Please follow this style to make TiDB easy to review, maintain and develop. ``` :