keycloak/docs/building.md

Building from source

Ensure you have JDK 17 or JDK 21 and Git installed

java -version
git --version

Newer versions of the JDK are not supported. If you have multiple JDK versions installed, you can specify which one to use during the build by setting the JAVA_HOME environment variable (this should be the directory containing /bin/ or /jre/).

JAVA_HOME=/path/to/jdk-21/ ./mvnw clean install

Instead of using a locally installed Maven, call the Maven wrapper script mvnw in the main folder of the project. This will use the Maven version which is supported by this project.

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First clone the Keycloak repository:

git clone https://github.com/keycloak/keycloak.git
cd keycloak

To build Keycloak without running the tests:

./mvnw clean install -DskipTests

To build Keycloak and run the tests (note that this might take several hours):

./mvnw clean install

To build Keycloak with adapters run:

./mvnw clean install -DskipTests -Pdistribution

To build only the server run:

./mvnw -pl quarkus/deployment,quarkus/dist -am -DskipTests clean install

You can then find the ZIP distribution in quarkus/dist/target folder.

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NOTE

Classes from org.keycloak.testsuite.* packages aren't suitable to be used in production.

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This project contains opt-in support for incremental Maven builds using the Apache Maven Build Cache Extension which is disabled by default.

To enable it for a single Maven command execution, enable it as follows:

./mvnw -D -Dmaven.build.cache.enabled=true ...

To enable it by default, add it to the MAVEN_OPTS environment variable:

export MAVEN_OPTS="-Dmaven.build.cache.enabled=true"

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NOTE

To ensure that development in a branch does not break compatibility with existing releases, proto-schema-compatibility-maven-plugin checks may be run, which can cause builds to fail in proxy environments. To avoid this, you can skip this check by adding the following property:

-DskipProtoLock=true

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Starting Keycloak

Follow the quarkus module documentation for instructions how to run Keycloak in dev environment.

Working with the codebase

We don't currently enforce a code style in Keycloak, but a good reference is the code style used by WildFly. This can be retrieved from Wildfly ide-configs.To import formatting rules, see following instructions.

If your changes require updates to the database read Updating Database Schema.

If your changes require introducing new dependencies or updating dependency versions please discuss this first on the dev mailing list. We do not accept new dependencies to be added lightly, so try to use what is available.

Building project from the IDE

Some parts of the project rely on generated code using Maven plugins. These steps might be skipped when building using IDE resulting in compilation errors. To work around this make sure to build the project first using Maven. After the initial build with Maven you should be able to build the project using the IDE as it will use the classes previously generated by Maven plugins. Make sure you don't rebuild the whole project using the IDE as it would delete the generated classes. E.g. in IntelliJ IDEA use Build → Build Project instead of Build → Rebuild Project.

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NOTE

If you are building the Operator from your IDE, make sure to build the project with the operator profile enabled in Maven as it's excluded by default:

./mvnw clean install -Poperator -DskipTests

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