From 809c7ee6e1d34654ae69a0cc02f72e7e61e8c7e5 Mon Sep 17 00:00:00 2001 From: Robert Bartel Date: Wed, 2 Oct 2024 14:54:20 -0400 Subject: [PATCH 1/3] Adding doc on release management. --- doc/RELEASE_MANAGEMENT.md | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 doc/RELEASE_MANAGEMENT.md diff --git a/doc/RELEASE_MANAGEMENT.md b/doc/RELEASE_MANAGEMENT.md new file mode 100644 index 0000000000..bab71035a8 --- /dev/null +++ b/doc/RELEASE_MANAGEMENT.md @@ -0,0 +1,39 @@ +# Release Management + +The page discusses the release process for official versions of _ngen_. This process is very much interrelated to the repo branching management model, as discussed in detail on the [GIT_USAGE](./GIT_USAGE.md) doc. + +# The Release Process + +## TL;DR + +The release process can be summarized fairly simply: +- A version name is finalized +- A release candidate branch is created +- Testing, QA, fixes are done on the release candidate branch +- Once release candidate is ready, changes are integrated into `production` and `master`, and the new version is tagged + +## Process Steps + + +[comment]: <> (TODO: Document release manual testing and QA procedures) +[//]: # (TODO: document testing and quality checks/process for release candidate prior to release) +[//]: # (TODO: document peer review and integration process for bug fixes, doc updates, etc., into release candidate branch prior to release (i.e, regular PR?) + +1. The next version number is decided/finalized + - Version numbering should follow [Semantic Versioning](https://semver.org/) and its typical `MAJOR.MINOR.PATCH` pattern +2. A release candidate branch, based on `master`, is created in the official OWP repo + - The name of this branch will be `release-X` for version `X` +3. All necessary testing and quality pre-release tasks are performed using this release candiate branch + - **TODO**: to be documented in more detail +4. (If necessary) Bug fixes, documentation updates, and other acceptable, non-feature changes are applied to the release branch + - Such changes should go through some peer review process before inclusion in the official OWP branch (e.g., PRs, out-of-band code reviews, etc.) + - **TODO**: process to be decided upon and documented +5. Steps 3. and 4. are repeated as needed until testing, quality checks, etc. in Step 3. do not require another iteration of Step 4. + - At this point, the branch is ready for official release +6. All changes in the release candidate branch are incorporated into `production` in the official OWP repo + - Note that **rebasing** should be used to reconcile changes ([see here](../CONTRIBUTING.md#a-rebase-strategy) for more info) +7. The subsequent `HEAD` commit of `production` is tagged with the new version in the official OWP repo +8. All changes in the release candidate branch are incorporated back into `master` in the official OWP repo + - This will include things like bug fixes committed to `release-X` after it was branched from `master` + - As with `production` in Step 6., this should be [done using rebasing](../CONTRIBUTING.md#a-rebase-strategy) +9. The release candidate branch is deleted from the OWP repo (and, ideally, other clones and forks) \ No newline at end of file From 3552160258f0c363ff5c0e1fa49354c8acce7581 Mon Sep 17 00:00:00 2001 From: Robert Bartel Date: Wed, 2 Oct 2024 14:54:43 -0400 Subject: [PATCH 2/3] Updating doc on Git usage to be more technical. --- doc/GIT_USAGE.md | 228 +++++++++++++++++++++++++++-------------------- 1 file changed, 132 insertions(+), 96 deletions(-) diff --git a/doc/GIT_USAGE.md b/doc/GIT_USAGE.md index 504ce0a113..d67b443fdc 100644 --- a/doc/GIT_USAGE.md +++ b/doc/GIT_USAGE.md @@ -1,107 +1,143 @@ # Git Strategy -- [Branching Design](#branching-design) -- [Contributing](#contributing) - - [TLDR;](#contributing-tldr) - - [Fork Consistency Requirements](#fork-consistency-requirements) - - [Fork Setup Suggestions](#fork-setup-suggestions) -- [Keeping Forks Up to Date](#keeping-forks-up-to-date) - - [Setting the upstream Remote](#setting-the-upstream-remote) - - [Getting Upstream Changes](#getting-upstream-changes) - - [Rebasing Development Branches](#rebasing-development-branches) - - [Fixing Diverging Development Branches](#fixing-diverging-development-branches) - -## Branching Design +Note that this document goes into detail on the Git strategy and branching model for the official OWP repository. It is here for openness and transparency, but most contributors and users will not need to be concerned with this level of detail. For information geared toward day-to-day development contributions and Git, see the [CONTRIBUTING](../CONTRIBUTING.md) doc. -- Main **upstream** repo has only the single long-term branch called **master**; i.e., `upstream/master` - - There may occasionally be other temporary branches for specific purposes -- Interaction with **upstream** repo is done exclusively via pull requests (PRs) to `upstream/master` +- [Branching Model](#branching-model) + - [Feature Branches from `master`](#feature-branches-from-master) + - [Relating `production`, `master`, and Release Branches](#relating-production-master-and-release-branches) +- [Contributing](#contributing) +- [Optional: Setting Up Hook Scripts](#optional-setting-up-hook-scripts) + +## Branching Model + +- This repo uses a branching model based on [Gitflow](https://nvie.com/posts/a-successful-git-branching-model/) that has two primary long-term branches: + - **master**: the main development and integration branch containing the latest completed development work intended for the next released version + - **production**: the branch representing the latest code verified as production-ready and pointing to the most recently release, official version +- Rebasing is used to integrate changes across branches, rather than merge commits + - This allows the repo to maintain a more robust and complete history +- Most interaction with the official OWP repo is done via pull requests (PRs) to the `master` branch + - Independent branches for features or bug fixes are created off `master` to contain development work that is in progress + - Once work in a feature/fix branch is complete (or at least thought complete), it is used to create a PR + - PRs and their linked branches are reviewed and, once approved, have their changes integrated back into `master` + - Typically feature/fix branches exist in personal clones and personal Github forks, but not in the official OWP repo +- Release branches (e.g., `release-X` for pending version `X`) will be created whenever it is time to officially release a new version + - These effectively are release candidates, with branches created from `master` + - The release branches are managed by the core OWP contributors team + - They do exist in the official OWP repo + - But they are short-lived and removed once the release becomes official + - See the [Release Management](RELEASE_MANAGEMENT.md) doc for more details on the release process + +### Feature Branches from `master` +This illustrates the relationship between feature branches and `master`. They should be created from `master` and independently contain commits from their feature. Once done, the changes will be reintegrated back into `master` via rebasing. + +```mermaid + %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': { 'showBranches': true, 'showCommitLabel':true, 'mainBranchName': 'master'}}}%% + gitGraph + commit id:"feature1.1" + commit id:"feature1.2" + branch feature-2 + branch feature-3 + checkout feature-2 + commit id:"feature2.1" + commit id:"feature2.2" + checkout master + merge feature-2 + checkout feature-3 + commit id:"feature3.1" + commit id:"feature3.2" + commit id:"feature3.3" + checkout master + merge feature-3 +``` + +The resulting state of `master` after rebasing the two new feature branches would be: + +```mermaid + %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': { 'showBranches': true, 'showCommitLabel':true, 'mainBranchName': 'master'}}}%% + gitGraph + commit id:"feature1.1" + commit id:"feature1.2" + commit id:"feature2.1" + commit id:"feature2.2" + commit id:"feature3.1" + commit id:"feature3.2" + commit id:"feature3.3" +``` + +### Relating `production`, `master`, and Release Branches + +This illustrates the relationship between `production`, `master`, and `release-v2`. Notice that `production` has already been tagged with version `v1` at the start. Commits for `feature1` and `feature2` at some point are integrated into `master`. When it is time to prepare to release version `v2`, `release-v2` is created. A few bug fix commits were needed in `release-v2`. After that, all the changes in `release-v2` are integrated into `production`, and `production` is tagged `v2`. All the changes are also integrated back into `master`. + + +```mermaid + %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': { 'showBranches': true, 'showCommitLabel':true, 'mainBranchName': 'master'}}}%% + gitGraph + commit id:"v1-commit" + branch production + checkout production + commit id:"v1-commit" tag: "v1" + checkout master + commit id:"feature1.1" + commit id:"feature1.2" + commit id:"feature2.1" + commit id:"feature2.2" + commit id:"feature2.3" + branch release-v2 + checkout release-v2 + commit id:"fix2.1" + commit id:"fix2.2" + checkout production + merge release-v2 tag:"v2" + checkout master + merge release-v2 + +``` + +The resulting state of `production` is: + +```mermaid + %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': { 'showBranches': true, 'showCommitLabel':true, 'mainBranchName': 'production'}}}%% + gitGraph + commit id:"v1-commit" tag:"v1" + commit id:"feature1.1" + commit id:"feature1.2" + commit id:"feature2.1" + commit id:"feature2.2" + commit id:"feature2.3" + commit id:"fix2.1" + commit id:"fix2.2" tag:"v2" +``` + +The resulting state of `master` is essentially the same: + +```mermaid + %%{init: { 'logLevel': 'debug', 'theme': 'base', 'gitGraph': { 'showBranches': true, 'showCommitLabel':true, 'mainBranchName': 'master'}}}%% + gitGraph + commit id:"v1-commit" + commit id:"feature1.1" + commit id:"feature1.2" + commit id:"feature2.1" + commit id:"feature2.2" + commit id:"feature2.3" + commit id:"fix2.1" + commit id:"fix2.2" +``` ## Contributing -- [TLDR;](#contributing-tldr) -- [Fork Consistency Requirements](#fork-consistency-requirements) -- [Fork Setup Suggestions](#fork-setup-suggestions) - -### Contributing TLDR; - -To work with the repo and contribute changes, the basic process is as follows: - -- Create your own fork in Github of the main **upstream** repository -- Clone your fork on your local development machine -- Make sure to keep your fork and your local clone(s) up to date with the main upstream repo, keeping histories consistent via rebasing -- In the local repo, push the changes you make to your Github fork -- Submit pull requests to `upstream/master` when you have changes ready to be added - -### Fork Consistency Requirements - -Within your own local repo and personal fork, you are mostly free to do whatever branching strategy works for you. However, branches used for PRs must have all new commits based on the current `HEAD` commit of the `upstream/master` branch, to ensure the repo history remains consistent. I.e., you need to make sure you rebase the branch with your changes before making a PR. How you go about this is up to you, but the following suggested setup will make that relatively easy. - -### Fork Setup Suggestions - -After creating your fork in Github, clone your local repo from the fork. This should make your fork a remote for you local repo, typically named **origin**. Then, [add the **upstream** as a second remote](#setting-the-upstream-remote) in your local repo. - -Have your own `master` branch, on your local clone and within your personal fork, just as [a place to rebase changes from `upstream/master`](#getting-upstream-changes). Do not do any development work or add any of your own changes directly. Just keep it as a "clean," current copy of the `upstream/master` branch. - -Use separate branches for development work as you see fit. When preparing to make a PR, create a new branch just for that PR, making sure it is both up to date with **upstream** and has all the desired local changes. Wait to actually push it to your fork until that has been done and your are ready create the PR. - -A separate, "clean" local `master` should be easy to keep it in sync with `upstream/master`, which in turn will make it relatively easy to rebase local development branches whenever needed. This simplifies maintaining the base-commit consistency requirement for the branches you will use for pull requests. - -Clean up above mentioned PR branches regularly (i.e., once their changes get incorporated). You may also want to do this for the other development branches in your fork, or else you'll end up with branches having [diverged histories that need to be fixed](#fixing-diverging-development-branches). - -## Keeping Forks Up to Date - -- [Setting the upstream Remote](#setting-the-upstream-remote) -- [Getting Upstream Changes](#getting-upstream-changes) -- [Rebasing Development Branches](#rebasing-development-branches) -- [Fixing Diverging Development Branches](#fixing-diverging-development-branches) - -### Setting the **upstream** Remote - -To stay in sync with other separate changes added to **upstream**, you will typically need to add the main upstream repository as a Git **remote** on your local development machine. The standard convention, used here and elsewhere, is to name that remote **upstream**. Doing the addition will look something like: - - # Add the remote - git remote add upstream https://github.com/NOAA-OWP/ngen.git - - # Verify - git remote -v - -### Getting Upstream Changes - -When you want to check for or apply updates to your fork (and your local repo), locally check out your `master` branch and do fetch-and-rebase, which can be done with `pull` and the `--rebase` option: - - # Checkout local master branch - git checkout master - - # Fetch and rebase changes - git pull --rebase upstream master - -Then, make sure these get pushed to your fork. Assuming a typical setup where you have cloned from your fork, and you still have `master` checked out, that is just: - - # Note the assumptions mentioned above that required for this syntax - git push - -Depending on your individual setup, you may want to do this immediately (e.g., if your `master` branch is "clean", as [discussed in the forking suggestions](#fork-setup-suggestions)), or wait until your local `master` is in a state ready to push to your fork. - -### Rebasing Development Branches - -When the steps in [Getting Upstream Changes](#getting-upstream-changes) do bring in new commits that update `master`, you should rebase your other local branches. E.g., +More details on the practical processes and requirements for contributing code changes can be found in the [CONTRIBUTING](../CONTRIBUTING.md) doc. In summary: - # If using a development branch named 'dev' - git checkout dev - git rebase master - -Alternatively, you can do an interactive rebase. This will open up a text editor allowing you to rearrange, squash, omit, etc. your commits when you rebase your development branch onto the new state of `master`. +- Github Pull Requests (PRs) are required to incorporate changes into the official OWP repo + - Contributors should generally not be pushing changes directly to branches in the OWP repo +- PRs should be submitted using a feature/fix branch contained in a personal Github fork +- Rebasing is used, rather than merge commits, to integrate changes across branches and keep branches from different repos in sync +- PRs should be configured to pull changes into the `master` branch +- Feature/fix branches should be created from `master` +- Personal forks and local clone(s) should be kept up to date with the official OWP repo regularly to minimize the introduction of merge conflict in PRs - git rebase -i master - -### Fixing Diverging Development Branches -If you have already pushed a local development branch to your fork, and then later need to rebase the branch, doing so will cause the history to diverge. If you are the only one using your fork, this is easy to fix by simply force-pushing your rebased local branch. +## Optional: Setting Up Hook Scripts - # To force-push to fix a divergent branch - git push -f origin dev - -However, you will need to be careful with this if you are not the only one using you fork (e.g., you are collaborating with someone else on a large set of changes for some new feature). The particular considerations and best ways to go about things in such cases are outside the scope of this document. Consult Git's documentation and Google, or contact another contributor for advice. +_Git_ supports the capability to automatically run various scripts when certain events happen. These are referred to as [_Git_ hooks](https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks). See Git's documentation for full details on what can be done with hooks and how they are configured. - \ No newline at end of file +Use of client-side hooks is optional but can be very useful for things like automating some kind of quality check before committing a change. However, client-side hooks are not copied as part of cloning a repository. They must be set up locally for each clone. This can be done manually or using available helper tools: e.g., [_pre-commit_](https://pre-commit.com/). Once again, see Git's docs for available options and setup details. \ No newline at end of file From 7654cf46d8e0e843c10a53cd349fbdf81119f95c Mon Sep 17 00:00:00 2001 From: Robert Bartel Date: Wed, 2 Oct 2024 14:55:06 -0400 Subject: [PATCH 3/3] Move practical, day-to-day Git info to CONTRIBUTING.md. --- CONTRIBUTING.md | 218 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 211 insertions(+), 7 deletions(-) diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index 859f86116e..e5d9f38f2e 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -1,4 +1,4 @@ -# Guidance on how to contribute +# Guidance on How to Contribute > All contributions to this project will be released to the public domain. > By submitting a pull request or filing a bug, issue, or @@ -7,11 +7,11 @@ There are two primary ways to help: - - Using the issue tracker, and - - Changing the code-base. +- Using the issue tracker, and +- Changing the code-base. -## Using the issue tracker +# Using the Issue Tracker Use the issue tracker to suggest feature requests, report bugs, and ask questions. This is also a great way to connect with the developers of the project as well @@ -22,8 +22,212 @@ the issue that you will take on that effort, then follow the _Changing the code- guidance below. -## Changing the code-base +# Changing the Code-Base -See the [Git Usage](doc/GIT_USAGE.md) document for more information about the process of working with the Git repository. +* [Summary](#summary) +* [Getting Started](#getting-started) +* [Developing Changes](#developing-changes) +* [Keeping Forks Up to Date](#keeping-forks-up-to-date) -All new code should have associated unit tests that validate implemented features and the presence or lack of defects. Additionally, the code should follow any stylistic and architectural guidelines prescribed by the project. In the absence of such guidelines, mimic the styles and patterns in the existing code-base. +Note that this document only discusses aspects of Git usage that should be needed for day-to-day development and contributions. For a more detailed overview of ngen's use of Git, see the [GIT_USAGE](doc/GIT_USAGE.md) doc. + +## Summary + +To work with the repo and contribute changes, the basic process is as follows: + +- Create your own fork in Github +- Clone the repo locally (conventionally from your fork) and [setup your repo on your local development machine](#getting-started) +- Make sure to [keep your fork and your local clone(s) up to date](#keeping-forks-up-to-date) with the official OWP ngen repo, ensuring histories remain consistent by performing [rebasing](#rebasing-development-branches) +- Create feature/fix branches from `master` when you want to contribute +- Write changes you want to contribute, commit to your local feature/fix branch, and push these commits to a branch in your personal Github fork +- Submit pull requests to the official OWP repo's `master` branch from a feature/fix branch your fork when the latter branch has a collection of changes ready to be incorporated + +## Getting Started + +In order to be able to contribute code changes, you will first need to [create a Github fork](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/fork-a-repo) of the official OWP repo. + +Next, set up your authentication mechanism with Github for your command line (or IDE). You can either [create an SSH key pair](https://docs.github.com/en/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent) and [add the public key](https://docs.github.com/en/authentication/connecting-to-github-with-ssh/adding-a-new-ssh-key-to-your-github-account) to your Github account, or you can set up a [Personal Access Token](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/managing-your-personal-access-tokens#using-a-personal-access-token-on-the-command-line) if you plan to clone the repo locally via HTTPS. + +After that, [clone a local development repo](https://docs.github.com/en/repositories/creating-and-managing-repositories/cloning-a-repository) from your fork, using a command similar to one of the following: + + # SSH-based clone command. Change URL to match your fork as appropriate + git clone git@github.com:your_user/ngen.git + + # HTTPS-based clone command. Change URL to match your fork as appropriate + git clone https://github.com/your_user/ngen.git + +You can now change directories into the local repo, which will have the _default_ branch - `master` for this repository - checked out. + + # Move into the repo directory "ngen" + cd ngen + + # You can verify the branch by examining the output of ... + git status + +> [!IMPORTANT] +> Git will add a [Git remote](https://git-scm.com/book/en/v2/Git-Basics-Working-with-Remotes) named `origin` to the clone's Git configuration that points to the cloned-from repo. Because of this, the recommended convention is to clone your local repo(s) from your personal fork, thus making `origin` point to your fork. This is assumed to be the case in other parts of the documentation. + +Next, add the OWP ngen repo as a second [Git remote](https://git-scm.com/book/en/v2/Git-Basics-Working-with-Remotes) for the local clone. Doing the addition will look something like: + + # Add the remote, here using the HTTPS URL (the SSH URL would be fine also) + git remote add upstream https://github.com/NOAA-OWP/ngen.git + + # Verify + git remote -v + +> [!IMPORTANT] +> The standard convention used in this doc and elsewhere is to name the Git remote for the official Github OWP repository `upstream`. In regular text, that Git remote will always be denoted like this. +> +> Git also has the more general concept of an "upstream branch" associated with "tracking branches", as discussed on the [Git Remote Branches](https://git-scm.com/book/en/v2/Git-Branching-Remote-Branches) documentation. We will use "upstream branch" when discussing these. + +Now set up the user and email in the local repo's configuration. + + git config user.name "John Doe" + git config user.email "john@doe.org" + +Alternatively, one could also set these in the machine's global Git config (or rely upon the global settings if already configured). + + git config --global user.name "John Doe" + git config --global user.email "john@doe.org" + +### Optional: Git Hooks + +While optional, Git hooks are a useful feature for helping maintain code quality in your local development repo. See the repo's [_Git Usage_](doc/GIT_USAGE.md#optional-setting-up-hook-scripts) document for more discussion on these. + +[//]: # (TODO: add section/document on code style) + + +## Developing Changes + +* [Work in a Dedicated Branch](#work-in-a-dedicated-branch) +* [Pushing Incremental Commits](#pushing-incremental-commits) +* [Submitting Pull Requests](#submitting-pull-requests) + * [Guidelines for Pull Requests](#guidelines-for-pull-requests) + +### Work in a Dedicated Branch + +When you want to contribute a fix or new feature, start by creating and checking out a local branch (e.g., `new_branch`) to contain your work. This should be based on `master` (you may need to [sync remote changes](#getting-remote-changes) first): + + # Create the new branch "new_branch" based on "master" + git branch new_branch master + + # Check out "new_branch" locally to work in it + git checkout new_branch + +Go ahead and push this new branch to your fork so it exists there as well. Use `-u` so that the local branch adds a tracking reference to the branch in your fork: + + # Assuming the convention of your fork's remote being `origin` + git push -u origin new_branch + +> [!IMPORTANT] +> While `-u` isn't strictly required, including it causes `origin/new_branch` to be set as the "upstream branch" for the local `new_branch` (with the latter being referred to as a "tracking branch"). Tracking branch relationships are described in the _Tracking Branches_ section of [Git's Remote Branches doc](https://git-scm.com/book/en/v2/Git-Branching-Remote-Branches). +> +> While it is totally optional, parts our documentation - especially example commands - may assume this tracking branch relationship has been set. + +From there begin writing and committing your changes to the branch. While up to you, it is suggested that development work be committed frequently when changes are complete and meaningful. If work requires modifying more than one file in the source, it is recommended to commit the changes independently to help avoid too large of conflicts if/when they occur. + +### Pushing Incremental Commits + +Especially if making more frequent, smaller commits as suggested above, it is a good practice to regularly push these smaller commits to your fork. If the `-u` option was used when initially pushing the branch, it is simple to check if there are local, unpushed commits. + + # The fetch is probably unnecesssary unless you work from multiple local repos + git fetch + + # Assuming your branch of interest is still checked out: + git status + + # And if there are some newer, local changes that haven't been push yet: + git push + +### Submitting Pull Requests + +Once a code contribution is finished, make sure all changes have been pushed to the branch in your fork. Then you can navigate to the OWP repo via Github's web interface and [submit a PR](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request) to pull this branch into the OWP `master` branch. Verify that `master` is selected as the recipient branch. You will also need to make sure you are comparing across forks, choosing your appropriate fork and branch to pull from. Complete details on the process can be found in Github's documentation. + +[//]: # (TODO: consider moving this to its own doc and expanding on details for PRs there some) + +#### Guidelines for Pull Requests + +The following guidelines are recommended for pull requests. Following these increases the likelihood of a PR being reviewed quickly and minimizes the amount of changes likely to be needed before approval: + +* Make sure the PR has an informative and human-readable title +* Limit the scope of changes within a PR to a single goal (no scope creep) +* Ensure the resulting code can be automatically rebased into `master` without conflicts +* Make sure project coding standards, if/when defined, are followed +* Ensure resulting code passes all existing automated tests +* Ensure any changes or additions to functionality are tested +* Document new functions with a description, list of inputs, and expected output +* Flag any placeholder code is flagged and note future TODO items in comments +* Update repo-level documentation appropriately +* Select one or more appropriate reviewers when creating the PR + +#### PR Review and Requested Revisions + +Once the PR is submitted, it will be reviewed by one or more other repo contributors. Often conversations will be had within the Github PR if reviewers have questions or request revisions be made to the proposed changes. If revisions are requested, you will need to make those in your locally copy of the feature/fix branch, and then re-push that branch (and the updates) to your personal fork. Then, use the PR page in Github to re-request review. + +## Keeping Forks Up to Date + +- [A Rebase Strategy](#a-rebase-strategy) +- [Getting Remote Changes](#getting-Remote-changes) +- [Rebasing Development Branches](#rebasing-development-branches) +- [Fixing Diverging Development Branches](#fixing-diverging-development-branches) + +### A Rebase Strategy + +Development for this repo uses a *rebase* strategy for integrating code changes, rather than a *merge* strategy. More information on rebasing is [available here](https://git-scm.com/book/en/v2/Git-Branching-Rebasing), but the main takeaway is that it is important all changes are integrated into branches using this approach. Deviation from this will likely cause a bit of mess with branch commit histories, which could force rejection of otherwise-good PRs. + +### Getting Remote Changes + +When it is time to check for or apply updates from the official OWP repo to a personal fork and/or a local repo, check out the `master` branch locally and do fetch-and-rebase, which can be done with `pull` and the `--rebase` option: + + # Checkout local master branch + git checkout master + + # Fetch and rebase changes + git pull --rebase upstream master + +Then, make sure these get pushed to your personal fork. Assuming [the above-described setup](#getting-started-with-your-fork) where the local repo was cloned from the fork, and assuming the local `master` branch is currently checked out, the command for that is just: + + # Note the assumptions mentioned above that are required for this syntax + git push + +Alternatively, you can use the more explicit form: + +`git push :` + +The previous example command is effectively equivalent to running: + + # Cloning a repo from a fork created a remote for the fork named "origin"; see above assumptions + git push origin master:master + +You also can omit `:` (including the colon) and supply just the remote branch name if the appropriate local branch is still checked out. + +#### For `production` Too + +Note that the above steps to get remote changes from the official OWP repo can be applied to the `production` branch also (just swap `production` in place of `master`). `production` should not be used as the basis for feature/fix branches, but there are other reasons why one might want the latest `production` locally or in a personal fork. + +### Rebasing Development Branches + +When the steps in [Getting Remote Changes](#getting-remote-changes) do bring in new commits that update `master`, it is usually a good idea (and often necessary) to rebase any local feature/fix branches were previously created. E.g., + + # If using a development branch named 'faster_dataset_writes' + git checkout faster_dataset_writes + git rebase master + +See documentation on [the "git rebase" command](https://git-scm.com/docs/git-rebase) for more details. + +#### Interactive Rebasing + +It is possible to have more control over rebasing by doing an interactive rebase. E.g.: + + git rebase -i master + +This will open up a text editor allowing for reordering, squashing, dropping, etc., development branch commits prior to rebasing them onto the new base commit from `master`. See the [**Interactive Mode**](https://git-scm.com/docs/git-rebase#_interactive_mode) section on the rebase command for more details. + +### Fixing Diverging Development Branches + +If a local feature/fix branch is already pushed to a remote fork, and then later rebasing the local branch is necessary, doing so will cause the histories to diverge. For simple cases, the fix is to just force-push the rebased local branch. + + # To force-push to fix a divergent branch + git push -f origin feature_branch + +However, extra care is needed if multiple developers may be using the branch in the fork (e.g., a developer is collaborating with someone else on a large set of changes for some new feature). The particular considerations and best ways to go about things in such cases are outside the scope of this document. Consult Git's documentation and Google, or contact another contributor for advice.