quarkus/CONTRIBUTING.md

# Contributing guide

**Want to contribute? Great!** 
We try to make it easy, and all contributions, even the smaller ones, are more than welcome.
This includes bug reports, fixes, documentation, examples... 
But first, read this page (including the small print at the end).

## Legal

All original contributions to Quarkus are licensed under the
[ASL - Apache License](https://www.apache.org/licenses/LICENSE-2.0),
version 2.0 or later, or, if another license is specified as governing the file or directory being
modified, such other license.

All contributions are subject to the [Developer Certificate of Origin (DCO)](https://developercertificate.org/).
The DCO text is also included verbatim in the [dco.txt](dco.txt) file in the root directory of the repository.

## Reporting an issue

This project uses GitHub issues to manage the issues. Open an issue directly in GitHub.

If you believe you found a bug, and it's likely possible, please indicate a way to reproduce it, what you are seeing and what you would expect to see.
Don't forget to indicate your Quarkus, Java, Maven/Gradle and GraalVM version. 

## Before you contribute

To contribute, use GitHub Pull Requests, from your **own** fork.

### Code reviews

All submissions, including submissions by project members, need to be reviewed before being merged.

### Continuous Integration

Because we are all humans, the project uses a continuous integration approach and each pull request triggers a full build.
Please make sure to monitor the output of the build and act accordingly.

### Tests and documentation are not optional

Don't forget to include tests in your pull requests. 
Also don't forget the documentation (reference documentation, javadoc...).

Be sure to test your pull request in:

1. Java mode
2. Native mode

## Setup

If you have not done so on this machine, you need to:
 
* Install Git and configure your GitHub access
* Install Java SDK (OpenJDK recommended)
* Install [GraalVM](https://quarkus.io/guides/building-native-image)
* Install platform C developer tools:
    * Linux
        * Make sure headers are available on your system (you'll hit 'Basic header file missing (<zlib.h>)' error if they aren't).
            * On Fedora `sudo dnf install zlib-devel`
            * Otherwise `sudo apt-get install libz-dev`
    * macOS
        * `xcode-select --install` 
* Set `GRAALVM_HOME` to your GraalVM Home directory e.g. `/opt/graalvm` on Linux or `$location/JDK/GraalVM/Contents/Home` on macOS

Docker is not strictly necessary: it is used to run the MariaDB and PostgreSQL tests which are not enabled by default. However it is a recommended install if you plan to work on Quarkus JPA support:

* Check [the installation guide](https://docs.docker.com/install/), and [the MacOS installation guide](https://docs.docker.com/docker-for-mac/install/)
* If you just install docker, be sure that your current user can run a container (no root required). 
On Linux, check [the post-installation guide](https://docs.docker.com/install/linux/linux-postinstall/)

### IDE Config and Code Style

Quarkus has a strictly enforced code style. Code formatting is done by the Eclipse code formatter, using the config files
found in the `independent-projects/ide-config` directory. By default when you run `./mvnw install` the code will be formatted automatically.
When submitting a pull request the CI build will fail if running the formatter results in any code changes, so it is
recommended that you always run a full Maven build before submitting a pull request.

If you want to run the formatting without doing a full build, you can run `./mvnw process-sources`.

#### Eclipse Setup

Open the *Preferences* window, and then navigate to _Java_ -> _Code Style_ -> _Formatter_. Click _Import_ and then
select the `eclipse-format.xml` file in the `independent-projects/ide-config` directory.

Next navigate to _Java_ -> _Code Style_ -> _Organize Imports_. Click _Import_ and select the `eclipse.importorder` file.

#### IDEA Setup

Open the _Preferences_ window (or _Settings_ depending on your edition) , navigate to _Plugins_ and install the [Eclipse Code Formatter Plugin](https://plugins.jetbrains.com/plugin/6546-eclipse-code-formatter) from the Marketplace.

Restart your IDE, open the *Preferences* (or *Settings*) window again and navigate to _Other Settings_ -> _Eclipse Code Formatter_.

Select _Use the Eclipse Code Formatter_, then change the _Eclipse Java Formatter Config File_ to point to the
`eclipse-format.xml` file in the `independent-projects/ide-config` directory. Make sure the _Optimize Imports_ box is ticked, and
select the `eclipse.importorder` file as the import order config file.


## Build

* Clone the repository: `git clone https://github.com/quarkusio/quarkus.git`
* Navigate to the directory: `cd quarkus`
* Invoke `./mvnw clean install` from the root directory

```bash
git clone https://github.com/quarkusio/quarkus.git
cd quarkus
./mvnw clean install
# Wait... success!
```

The default build does not create native images, which is quite time consuming.

Note that the full build with all tests is quite slow, you will usually want to build with `-DskipTests`. This will also
skip creation of the integration-test runner jars. If you want to skip tests but still create the runners you can set
`-DskipTests -Dquarkus.build.skip=false`

You can build and test native images in the integration tests supporting it by using `./mvnw install -Dnative`.

By default the build will use the native image server. This speeds up the build, but can cause problems due to the cache
not being invalidated correctly in some cases. To run a build with a new instance of the server you can use
`./mvnw install -Dnative-image.new-server=true`.

### MicroProfile TCK's

Quarkus has a TCK module in `tcks` where all the MicroProfile TCK's are set up for you to run if you wish. These 
include tests to areas like Config, JWT Authentication, Fault Tolerance, Health Checks, Metrics, OpenAPI, OpenTracing, 
REST Client, Reactive Messaging and Context Propagation.

The TCK module is not part of the main Maven reactor build, but you can enable it and run the TCK tests by activating 
the Maven Profile `-Ptcks`. If your work is related to any of these areas, running the TCK's is highly recommended to 
make sure you are not breaking the project. The TCK's will also run on any Pull Request.

You can either run all of the TCK's or just a subset by executing `mvn verify` in the `tcks` module root or each of 
the submodules. If you wish to run a particular test, you can use Maven `-Dtest=` property with the fully qualified 
name of the test class and optionally the method name by using 
`mvn verify -Dtest=fully.qualified.test.class.name#methodName`.

### Test Coverage

Quarkus uses Jacoco to generate test coverage. If you would like to generate the report run `mvn install -Ptest-coverage`,
then change into the `coverage-report` directory and run `mvn package`. The code coverage report will be generated in
`target/site/jacoco/`.

This currently does not work on Windows as it uses a shell script to copy all the classes and files into the code coverage
module.

## The small print

This project is an open source project, please act responsibly, be nice, polite and enjoy!

## Frequently Asked Questions

* IntelliJ fails to import Quarkus Maven project with `java.lang.OutOfMemoryError: GC overhead limit exceeded` 

In IntelliJ IDEA (version older than `2019.2`) if you see problems in the Maven view claiming `java.lang.OutOfMemoryError: GC overhead limit exceeded` that means the project import failed.
  
To fix the issue, you need to update the Maven importing settings:  
`Build, Execution, Deployment` > `Build Tools`> `Maven` > `Importing` > `VM options for importer`
To import Quarkus you need to define the JVM Max Heap Size (E.g. `-Xmx1g`)

**Note** As for now, we can't provide a unique Max Heap Size value. We have been reported to require from 768M to more than 3G to import Quarkus properly.

* Build hangs with DevMojoIT running infinitely 
```
./mvnw clean install
# Wait...
[INFO] Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 6.192 s - in io.quarkus.maven.it.GenerateConfigIT
[INFO] Running io.quarkus.maven.it.DevMojoIT

```
DevMojoIT require a few minutes to run but anything more than that is not expected. Make sure that nothing is running on 8080.

* The native integration test for my extension didn't run in the CI

In the interest of speeding up CI, the native build stage `run_native_tests_stage` have been split into multiple steps. 
This means that each new extension needs to be configured explicitly in `azure-pipelines.yml` to have it's integration tests run in native mode