• Generator development setup

JHipster is a Yeoman Generator, so you must follow the Yeoman authoring documentation in order to be able to run and test your changes.

Here are the most important steps.

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.

Please read the GitHub forking documentation for more information

Since v8 generator-jhipster is written in TypeScript. To run it you need to compile to JavaScript or use a just-in-time compilation.

The executable is located at bin/jhipster.cjs. You can alias it to jhipster command:

alias jhipster="GLOBAL_PATH/generator-jhipster/bin/jhipster.cjs"

In your cloned generator-jhipster project, run npm ci and then run npm link.

npm ci will do a clean installation of all the project dependencies and compile sources. npm run build can be used to compile sources after each change.

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.

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 jhipster --no-skip-jhipster-dependencies.

To put it in a nutshell, you need to:

1. Run npm link on the generator-jhipster project (link globally) or configure jit executable
2. Run jhipster --skip-jhipster-dependencies on the generated application folder

You can execute jhipster --install-path to check where JHipster is being executed from.

You can test your setup by making a small change in your cloned generator, and running again on an existing JHipster project:

For projects with JHipster third-party libraries (i.e. react-jhipster, etc.), you need to run npm link on the library project as well, then npm link the original framework (i.e. react) from the generated project to the library project cd react-jhipster && npm link <path-to-generated-project>/node_modules/react.

jhipster

Depending on which parts of the generator you have changed, do not forget to run the jhipster command with the proper arguments e.g. when updating the entity template run:

jhipster --with-entities

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; #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"

As modifying the JHipster generator includes modifying Java and JavaScript templates, most IDE will not work correctly. We recommend you use a text editor like VSCode or IntelliJ IDEA to code your changes. The ESLint and EditorConfig extensions are recommended to help with respecting code conventions.

It is possible to debug JHipster's code using a Node.js debugger. To achieve this setup your debugger to launch cli/jhipster.js.

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/Cmd Shift D). This will start the generator in debug mode and generate files in the test-integration/samples/app-sample-dev folder.

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 .vscode/launch.json file.

Run every test with lint/prettier npm test

Run every test without lint/prettier npx esmocha

Update every test snapshot npm run update-snapshots

Run specific tests npx esmocha <path>

Run specific tests in series (improved error reporting) npx esmocha <path> --no-parallel

Update specific test snapshot npm run update-snapshot -- <path> or npx esmocha <path> --no-parallel --update-snapshot

Fixing lint and prettier errors npm run lint-fix

Sample generating is provided by generator-jhipster local blueprint which we will refer as dev blueprint. The dev blueprint is enabled by running jhipster in JIT mode (executing ./bin/jhipster.cjs file relative to this file).

jhipster generate-sample ng-default will generate the ng-default sample at current folder.

Daily builds samples are prefixed with daily-.

A common samples folder will be used if --global option is used like jhipster generate-sample ng-default --global. At first execution a prompt will ask for the samples folder, the chosen value will be reused at next executions. At samples folder, a jhipster-samples.code-workspace is generated. It provides a single vscode workspace for generator-jhipster and samples generated at the samples folder. It's very used for quick looks.

CI tests use the following commands:

npm ci:backend:test
npm ci:frontend:test
npm run ci:e2e:package # Builds the application
npm run ci:e2e:prepare # Starts the application using docker
npm run ci:e2e:run # Runs e2e tests

generator-jhipster add a series of vscode configurations for a better developer experience.

A container is built using Java, Node, and npm as recommended by generator-jhipster. Once up, you should have the stack maintainers recommends.

Shortcuts are provided to easily generate integration tests samples.

• go to Execute and Debug.
• select the sample's GitHub workflow.
• run the shortcut.
• select the sample.
• sample is generated at ../jhipster-samples/ folder relative the generator-jhipster folder.

Some daily builds samples are available too.

At test tab you can run and debug individual test.

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('../common/field_validators', {field, reactive}); -%>

This statement means that PersistClass.java.jhi.jakarta_validation.ejs template includes field_validators.ejs sub template.

Sub templates can be unit tested.