Contributing to JHipster
Are you ready to contribute to JHipster? We'd love to have you on board, and we will help you as much as we can. Here are the guidelines we'd like you to follow so that we can be of more help:
- Questions and help
- Issues and Bugs
- Bug bounties
- Feature Requests
- Submission Guidelines
- Generator development setup
- Coding Rules
- Git Commit Guidelines
And don't forget we also accept financial contributions to the project using OpenCollective.
If you find a bug in the source code or a mistake in the documentation, you can help us by submitting a ticket to our GitHub issues. Even better, you can submit a Pull Request to our JHipster generator project or to our Documentation project.
Please see the Submission Guidelines below.
If you submitted a Pull Request that fixes a ticket with the "$100" tag, then you are eligible to our bug bounty program! Go to our bug bounties documentation for more information, and claim your money.
You can request a new feature by submitting a ticket to our GitHub issues. If you would like to implement a new feature then consider what kind of change it is:
- Major Changes that you wish to contribute to the project should be discussed first. Please open a ticket which clearly states that it is a feature request in the title and explain clearly what you want to achieve in the description, and the JHipster team will discuss with you what should be done in that ticket. You can then start working on a Pull Request. In order to communicate major changes proposals and receive reviews from the core team, you can also submit an RFC.
- Small Changes can be proposed without any discussion. Open up a ticket which clearly states that it is a feature request in the title. Explain your change in the description, and you can propose a Pull Request straight away.
Sometimes, major feature requests are "complex" or "substantial". In this case, GitHub Issues might not be the best tool to to present them because we will need a lot of going back and forth to reach a consensus.
So we ask that these feature request be put through a formal design process and have their specifications described in an "RFC" (request for comments) that will be validated by the team through a Pull Request Review.
The RFC process is intended to provide a consistent and controlled path for major features and directions of the project.
To submit an RFC follow those steps:
- Discuss the RFC proposal with the core team through GitHub issues or other channels
- Create the initial GitHub issue for the Feature Request if it doesn't already exist
- Copy the
- Fill in the RFC, make sure to complete every required section
- Submit the RFC as a Pull Request with the summary of the proposal in the PR description
- Build consensus and integrate feedback from the reviewers
- The Pull Request is either accepted (merged), rejected (closed) or postponed (given an "on hold" status)
Note: The JHipster RFC process is inspired by Rust RFCs.
Before you submit your issue search the archive, maybe your question was already answered.
If your issue appears to be a bug, and has not been reported, open a new issue. Help us to maximize the effort we can spend fixing issues and adding new features, by not reporting duplicate issues. Providing the following information will increase the chances of your issue being dealt with quickly:
- Overview of the issue - if an error is being thrown a stack trace helps
- Motivation for or Use Case - explain why this is a bug for you
- Related issues - has a similar issue been reported before?
- Suggest a Fix - if you can't fix the bug yourself, perhaps you can point to what might be causing the problem (line of code or commit)
- JHipster Version(s) - is it a regression?
- JHipster configuration, a
.yo-rc.jsonfile generated in the root folder - this will help us to replicate the scenario, you can remove the rememberMe key.
- Entity configuration(s)
entityName.jsonfiles generated in the
.jhipsterdirectory - if the error is during an entity creation or associated with a specific entity
- Browsers and Operating System - is this a problem with all browsers or only IE8?
You can use
jhipster info to provide us the information we need.
You can run
jhipster info in your project folder to get most of the above required info.
Issues opened without any of these info will be closed without any explanation.
Before you submit your pull request consider the following guidelines:
Search GitHub for an open or closed Pull Request that relates to your submission.
If you want to modify the JHipster generator, read our Generator development setup
Make your changes in a new git branch
git checkout -b my-fix-branch main
Create your patch, including appropriate test cases.
Follow our Coding Rules.
Generate a new JHipster project, and ensure that all tests pass
mvnw verify -Pprod
Test that the new project runs correctly:
You can generate our Continuous Integration (with GitHub Actions and Azure Pipelines) by following this
Commit your changes using a descriptive commit message that follows our commit message conventions.
git commit -a
Note: the optional commit
-acommand line option will automatically "add" and "rm" edited files.
Push your branch to GitHub:
git push origin my-fix-branch
In GitHub, send a pull request to
If we suggest changes then
Make the required updates.
Re-run the JHipster tests on your sample generated project to ensure tests are still passing.
Rebase your branch and force push to your GitHub repository (this will update your Pull Request):
git rebase main -i git push -f
That's it! Thank you for your contribution!
Resolving merge conflicts ("This branch has conflicts that must be resolved")
Sometimes your PR will have merge conflicts with the upstream repository's main branch. There are several ways to solve this but if not done correctly this can end up as a true nightmare. So here is one method that works quite well.
First, fetch the latest information from the main
git fetch upstream
Rebase your branch against the upstream/main
git rebase upstream/main
Git will stop rebasing at the first merge conflict and indicate which file is in conflict. Edit the file, resolve the conflict then
git add <the file that was in conflict> git rebase --continue
The rebase will continue up to the next conflict. Repeat the previous step until all files are merged and the rebase ends successfully.
Re-run the JHipster tests on your sample generated project to ensure tests are still passing.
Force push to your GitHub repository (this will update your Pull Request)
git push -f
After your pull request is merged
After your pull request is merged, you can safely delete your branch and pull the changes from the main (upstream) repository:
Delete the remote branch on GitHub either through the GitHub web UI or your local shell as follows:
git push origin --delete my-fix-branch
Check out the main branch:
git checkout main -f
Delete the local branch:
git branch -D my-fix-branch
Update your main with the latest upstream version:
git pull --ff upstream main
Here are the most important steps.
Fork the generator-jhipster project
Go to the generator-jhipster project and click on the "fork" button. You can then clone your own fork of the project, and start working on it.
Set NPM to use the cloned project
In your cloned
generator-jhipster project, run
npm link and then run
npm link will make a symbolic link from the global
node_modules version to point to this folder, so when we run
jhipster, you will now use the development version of JHipster.
npm ci will do a clean install of all of the project dependencies.
For testing, you will want to generate an application, and there is a specific issue here: for each application, JHipster installs a local version of itself. This is made to enable several applications to each use a specific JHipster version (application A uses JHipster 3.1.0, and application B uses JHipster 3.2.0).
To overcome this you need to run
npm link generator-jhipster on the generated project folder as well, so that the local version has a symbolic link to the development version of JHipster.
Also add the option
--skip-jhipster-dependencies to generate the application ignoring the JHipster dependencies (otherwise a released version will be installed each time npm install/ci is called). You can later on re-add the dependency with the command
To put it in a nutshell, you need to:
npm linkon the
generator-jhipsterproject (link globally)
jhipster --skip-jhipster-dependencieson the generated application folder
You can execute
jhipster --install-path to check where jhipster is been executed from.
You can test your setup by making a small change in your cloned generator, and running again on an existing JHipster project:
Depending on which parts of the generator you have changed, do not forget to run jhipster command with the proper arguments e.g. when updating the entity template run:
You should see your changes reflected in the generated project.
Note: The generated project might not build properly in case the generator is using a snapshot version of jhipster/jhipster-bom. This issue is mentioned in; https://github.com/jhipster/generator-jhipster/issues/9571. In this case clone the jhipster/jhipster-bom project and build it using:
./mvnw clean install -Dgpg.skip=true
or on Windows:
.\mvnw.cmd clean install -D"gpg.skip=true"
Use a text editor
Use a debugger
It is possible to debug JHipster's code using a Node.js debugger. To achieve this, setup your debugger to launch
Debugging with VSCode
To start debugging JHipster with VSCode, open the generator code in your workspace and simply press F5 (or click the green arrow in the Debug menu reachable with Ctrl+Shift+D). This will start the generator in debug mode and generate files in the
It is also possible to debug sub generators by selecting one of the other debug options (for example
jhipster entity). Those debug configurations are specified in the
Generator tests and snapshots.
Run every test with lint/prettier
Run every test without lint/prettier
Update every test snapshot
npm run update-snapshots
Run specific tests
npx mocha <path>
Run specific tests in series (improved error reporting)
npx mocha <path> --no-parallel
Update specific test snapshot
npm run update-snapshot -- <path> or
npx mocha <path> --no-parallel --updateSnapshot
Fixing lint and prettier errors
npm run lint-fix
Running integration tests locally
You can run the builds locally by following below commands
Go into the
test-integration folder with
cd test-integration from the generator source code root folder
./generate-sample.sh <command_name> [folder] [sample_name:optional] [type of entity]
This will create a folder with configuration and entities. Then, you can generate manually a JHipster project and test it.
Command name can be as below
`list`: List all sample names `generate`: Generate the sample
To ensure consistency throughout the source code, keep these rules in mind as you are working:
- All features or bug fixes must be tested by one or more tests.
- All files must follow the .editorconfig file located at the root of the JHipster generator project. Please note that generated projects use the same
.editorconfigfile, so that both the generator and the generated projects share the same configuration.
- Java files must be formatted using Intellij IDEA default code style.
- Any client side feature/change should be done for both Angular and react clients
- Angular Typescript files must follow the Official Angular style guide.
- React/Redux Typescript files may follow the React/Redux Typescript guide.
Please ensure to run
npm run lint and
npm test on the project root before submitting a pull request. You can also run
npm run lint-fix to fix some of the lint issues automatically.
The template engine used by yeoman is EJS, its syntax is fairly simple. For simple code (few lines), logic can be embedded in the main file but if logic becomes more complex it's better to externalise the JS fragment to a sub template included by the first one and located in same folder.
Sub templates should be named with the
ejs extension because it's the default one, it enables editors to apply correct syntax highlighting and it enables us to use a very concise syntax:
<%- include('field_validators'); -%>
Sub templates can be unit tested.
We have rules over how our git commit messages must be formatted. Please ensure to squash unnecessary commits so that your commit history is clean.
If the commit only involves documentation changes you can skip the continuous integration pipelines using
[ci skip] or
[skip ci] in your commit message header.
Each commit message consists of a header, a body and a footer.
<header> <BLANK LINE> <body> <BLANK LINE> <footer>
Any line of the commit message cannot be longer 100 characters! This allows the message to be easier to read on GitHub as well as in various git tools.
The Header contains a succinct description of the change:
- use the imperative, present tense: "change" not "changed" nor "changes"
- don't capitalize first letter
- no dot (.) at the end
If your change is simple, the Body is optional.
Just as in the Header, use the imperative, present tense: "change" not "changed" nor "changes". The Body should include the motivation for the change and contrast this with previous behavior.
The footer is the place to reference GitHub issues that this commit Closes.
You must use the GitHub keywords for automatically closing the issues referenced in your commit.
For example, here is a good commit message:
upgrade to Spring Boot 1.1.7 upgrade the Maven and Gradle builds to use the new Spring Boot 1.1.7, see http://spring.io/blog/2014/09/26/spring-boot-1-1-7-released Fix #1234
Regular Contributor Guidelines
These are some of the guidelines that we would like to emphasize if you are a regular contributor to the project or joined the JHipster team.
- We recommend not committing directly to main, but always submit changes through PRs.
- Before merging, try to get at least one review on the PR.
- Add appropriate labels to issues and PRs that you create (if you have permission to do so).
- Follow the project's policies.
- Follow the project's Code of Conduct and be polite and helpful to users when answering questions/bug reports and when reviewing PRs.
- We work on our free time so we have no obligation nor commitment. Work/life balance is important, so don't feel tempted to put in all your free time fixing something.