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
- Reporting an issue
- Checking an issue is fixed in main
- Before you contribute
- Setup
- Build
- Usage
- Extensions
- The small print
- Frequently Asked Questions
Table of contents generated with markdown-toc
All original contributions to Quarkus are licensed under the ASL - Apache License, 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). The DCO text is also included verbatim in the dco.txt file in the root directory of the repository.
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.
Sometimes a bug has been fixed in the main
branch of Quarkus and you want to confirm it is fixed for your own application.
Testing the main
branch is easy and you have two options:
- either use the snapshots we publish daily on https://oss.sonatype.org/content/repositories/snapshots/
- or build Quarkus all by yourself
This is a quick summary to get you to quickly test main. If you are interested in having more details, refer to the Build section and the Usage section.
Snapshots are published daily so you will have to wait for a snapshot containing the commits you are interested in.
Then just add https://oss.sonatype.org/content/repositories/snapshots/ as a Maven repository and a plugin repository.
You can check the last publication date here: https://oss.sonatype.org/content/repositories/snapshots/io/quarkus/ .
Just do the following:
git clone [email protected]:quarkusio/quarkus.git
cd quarkus
export MAVEN_OPTS="-Xmx1563m"
./mvnw -Dquickly
Wait for a bit and you're done.
Be careful, when using the main
branch, you need to use the quarkus-bom
instead of the quarkus-universe-bom
.
Update both the versions of the quarkus-bom
and the Quarkus Maven plugin to 999-SNAPSHOT
.
You can now test your application.
To contribute, use GitHub Pull Requests, from your own fork.
Also, make sure you have set up your Git authorship correctly:
git config --global user.name "Your Full Name"
git config --global user.email [email protected]
If you use different computers to contribute, please make sure the name is the same on all your computers.
We use this information to acknowledge your contributions in release announcements.
All submissions, including submissions by project members, need to be reviewed before being merged.
- We decided to disallow
@author
tags in the Javadoc: they are hard to maintain, especially in a very active project, and we use the Git history to track authorship. GitHub also has this nice page with your contributions. For each major Quarkus release, we also publish the list of contributors in the announcement post. - Commits should be atomic and semantic. Please properly squash your pull requests before submitting them. Fixup commits can be used temporarily during the review process but things should be squashed at the end to have meaningful commits. We use merge commits so the GitHub Merge button cannot do that for us. If you don't know how to do that, just ask in your pull request, we will be happy to help!
Because we are all humans, and to ensure Quarkus is stable for everyone, all changes must go through Quarkus continuous integration. Quarkus CI is based on GitHub Actions, which means that everyone has the ability to automatically execute CI in their forks as part of the process of making changes. We ask that all non-trivial changes go through this process, so that the contributor gets immediate feedback, while at the same time keeping our CI fast and healthy for everyone.
The process requires only one additional step to enable Actions on your fork (clicking the green button in the actions tab). See the full video walkthrough for more details on how to do this.
To keep the caching of non-Quarkus artifacts efficient (speeding up CI), you should occasionally sync the main
branch of your fork with main
of this repo (e.g. monthly).
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:
- Java mode
- Native mode
If you have not done so on this machine, you need to:
- Install Git and configure your GitHub access
- Install Java SDK 8 or 11+ (OpenJDK recommended)
- Install GraalVM
- 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
- On Fedora
- Make sure headers are available on your system (you'll hit 'Basic header file missing (<zlib.h>)' error if they aren't).
- macOS
xcode-select --install
- Linux
- 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, and the MacOS installation guide
- 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
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
.
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.
Quarkus is a large project and IDEA will have a hard time compiling the whole of it.
Before you start coding, make sure to build the project using Maven from the commandline
with ./mvnw -Dquickly
.
After creating an IDEA project, the first import will most likely fail with an OutOfMemoryError
.
To fix that, open the Preferences window (or Settings depending on your edition),
then navigate to Build, Execution, Deployment > Build Tools > Maven > Importing.
In VM options for importer, raise the heap to at least 2 GB, e.g. -Xmx2g -Xms2g
.
You may get an error like this during the build:
Error:(46, 56) java: package sun.misc does not exist
To fix this go to Settings > Build, Execution, Deployment > Compiler > Java Compiler and disable Use '--release' option for cross compilation (java 9 and later).
Open the Preferences window (or Settings depending on your edition), navigate to Plugins and install the Eclipse Code Formatter Plugin 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.
Next, disable wildcard imports:
navigate to Editor -> Code Style -> Java -> Imports
and set Class count to use import with '*' to 999
.
Do the same with Names count to use static import with '*'.
- Clone the repository:
git clone https://github.com/quarkusio/quarkus.git
- Navigate to the directory:
cd quarkus
- Set Maven heap to 1.5GB
export MAVEN_OPTS="-Xmx1563m"
- Invoke
./mvnw -Dquickly
from the root directory
git clone https://github.com/quarkusio/quarkus.git
cd quarkus
export MAVEN_OPTS="-Xmx1563m"
./mvnw -Dquickly
# Wait... success!
This build skipped all the tests, native-image builds, documentation generation etc. and used the Maven goals clean install
by default.
For more details about -Dquickly
have a look at the quick-build
profile in quarkus-parent
(root pom.xml
).
Adding -DskipTests=false -DskipITs=false
enables the tests.
It will take much longer to build but will give you more guarantees on your code.
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
.
Due to Quarkus being a large repository, having to rebuild the entire project every time a change is made isn't very productive. The following Maven tips can vastly speed up development when working on a specific extension.
Let's say you want to make changes to the Jackson
extension. This extension contains the deployment
, runtime
and spi
modules
which can all be built by executing following command:
./mvnw install -f extensions/jackson/
This command uses the path of the extension on the filesystem to identify it. Moreover, Maven will automatically build all modules in that path recursively.
Let's say you want to make changes to the deployment
module of the Jackson extension. There are two ways to accomplish this task as shown by the following commands:
./mvnw install -f extensions/jackson/deployment
or
./mvnw install --projects 'io.quarkus:quarkus-jackson-deployment'
In this command we use the groupId and artifactId of the module to identify it.
Often you need to run a single test from some Maven module. Say for example you want to run the GreetingResourceTest
of the resteasy-jackson
Quarkus integration test (which can be found here).
One way to accomplish this is by executing the following command:
./mvnw test -f integration-tests/resteasy-jackson/ -Dtest=GreetingResourceTest
ℹ️ This feature is currently in testing mode. You're invited to give it a go and please reach out via Zulip or GitHub in case something doesn't work as expected or you have ideas to improve things.
Instead of manually specifying the modules to build as in the previous examples, you can tell gitflow-incremental-builder (GIB) to only build the modules that have been changed or depend on modules that have been changed (downstream). E.g.:
./mvnw install -Dincremental
This will build all modules (and their downstream modules) that have been changed compared to your local main
, including untracked and uncommitted changes.
If you just want to build the changes since the last commit on the current branch, you can switch off the branch comparison via -Dgib.disableBranchComparison
(or short: -Dgib.dbc
).
There are many more configuration options in GIB you can use to customize its behaviour: https://github.com/gitflow-incremental-builder/gitflow-incremental-builder#configuration
Parallel builds (-T...
) should work without problems but parallel test execution is not yet supported (in general, not a GIB limitation).
Without going too much into details (devtools/bom-descriptor-json/pom.xml
has more info), you should build this module without -Dincremental
if you changed any extension "metadata":
- Addition/renaming/removal of an extension
- Any other changes to any
quarkus-extension.yaml
The GitHub Actions based Quarkus CI is using GIB to reduce the average build time of pull request builds and builds of branches in your fork.
CI is using a slighty different GIB config than locally:
- Special handling of "Explicitly selected projects" is deactivated
- Untracked/uncommitted changes are not considered
- Branch comparison is more complex due to distributed GitHub forks
- Certain "critical" branches like
main
are not built incrementally
For more details see the Get GIB arguments
step in .github/workflows/ci-actions-incremental.yml
.
After the build was successful, the artifacts are available in your local Maven repository.
To include them into your project a few things have to be changed.
pom.xml
<properties>
<quarkus-plugin.version>999-SNAPSHOT</quarkus-plugin.version>
<quarkus.platform.artifact-id>quarkus-bom</quarkus.platform.artifact-id>
<quarkus.platform.group-id>io.quarkus</quarkus.platform.group-id>
<quarkus.platform.version>999-SNAPSHOT</quarkus.platform.version>
.
.
.
</properties>
gradle.properties
quarkusPlatformArtifactId=quarkus-bom
quarkusPluginVersion=999-SNAPSHOT
quarkusPlatformVersion=999-SNAPSHOT
quarkusPlatformGroupId=io.quarkus
settings.gradle
pluginManagement {
repositories {
mavenLocal() // add mavenLocal() to first position
mavenCentral()
gradlePluginPortal()
}
.
.
.
}
build.gradle
repositories {
mavenLocal() // add mavenLocal() to first position
mavenCentral()
}
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
.
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.
If you just need a report for a single module, run mvn install jacoco:report -Ptest-coverage
in that module (or with -f ...
).
Extensions descriptions (in the runtime/pom.xml
description or in the YAML quarkus-extension.yaml
)
are used to describe the extension and are visible in https://code.quarkus.io.
Try and pay attention to it.
Here are a few recommendation guidelines:
- keep it relatively short so that no hover is required to read it
- describe the function over the technology
- use an action / verb to start the sentence
- do no conjugate the action verb (
Connect foo
, notConnects foo
norConnecting foo
) - connectors (JDBC / reactive) etc tend to start with Connect
- do not mention
Quarkus
- do not mention
extension
- avoid repeating the extension name
Bad examples and the corresponding good example:
- "AWS Lambda" (use "Write AWS Lambda functions")
- "Extension for building container images with Docker" (use "Build container images with Docker")
- "PostgreSQL database connector" (use "Connect to the PostgreSQL database via JDBC")
- "Asynchronous messaging for Reactive Streams" (use "Produce and consume messages and implement event driven and data streaming applications")
When adding a new extension you should run update-extension-dependencies.sh
so that special modules like devtools/bom-descriptor-json
that are consuming this extension are built after the respective extension. Simply add to your commit the files that were changed by the script.
When removing an extension make sure to also remove all dependencies to it from all pom.xml
.
It's easy to miss this as long as the extension artifact is still present in your local Maven repository.
This project is an open source project, please act responsibly, be nice, polite and enjoy!
-
The Maven build fails with
OutOfMemoryException
Set Maven options to use 1.5GB of heap:
export MAVEN_OPTS="-Xmx1563m"
. -
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 claimingjava.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 job
native-tests
have been split into multiple categories which are run in parallel. This means that each new extension needs to be configured explicitly innative-tests.json
to have its integration tests run in native mode. -
Build aborts complaining about missing (or superfluous)
minimal *-deployment dependencies
orillegal runtime dependencies
To ensure a consistent build order, even when building in parallel (
./mvnw -T...
) or building incrementally/partially (./mvnw -pl...
), the build enforces the presence of certain dependencies. If those dependencies are not present, your local build will most likely use possibly outdated artifacts from you local repo and CI build might even fail not finding certain artifacts.Just do what the failing enforcer rule is telling you and you should be fine.
-
Build fails with multiple
This project has been banned from the build due to previous failures
messagesJust scroll up, there should be an error or warning somewhere. Failing enforcer rules are known to cause such effects and in this case there'll be something like:
[WARNING] Rule 0: ... failed with message: ...