How-to build the project

Project organization

This a muti-module projects. The modules are (in build order)

  • graphql-maven-plugin-project: The root pom. It contains the pages for the site, and its pom contains the declaration for every dependency and plugin version.
  • graphql-java-client-dependencies: This project is just a pom, that contains the dependencies for the client mode.
  • graphql-java-server-dependencies: This project is just a pom, that contains the dependencies for the server mode.
  • graphql-java-runtime: This project contains the code that is necessary at runtime. Its source is copied along with the generated source, so that no dependency from graphql-java-generator is necessary at runtime. And this insures that the runtime is of the good version, as expected by the generated code.
  • graphql-maven-plugin-logic: The heart of the plugin. This project contains the code that parses the GraphQL schema, then generates the code. It's reused for the Maven plugin and the Gradle plugin.
  • graphql-maven-plugin: This project embeds the graphql-maven-plugin-logic into a Maven plugin.
  • graphql-maven-plugin-samples: Just a container for all the samples for this project. All these projects are both samples and integration tests. For each sample, there is a server and a client. The client project depends on the server one: the integration tests are in the client project. The client project starts the server, then execute integration tests against it.
  • graphql-maven-plugin-samples-allGraphQLCases-server. This project is more used as integration test than a real sample, as there is no real functionality. It contains various combinations that allow to validate the generated code, especially the AllGraphQLCases type. It also contains some Custom Scalars. The server is package as a Spring Boot application, and is executed on a http URL.
  • graphql-maven-plugin-samples-allGraphQLCases-client. This project allows to test complex behaviors on client side, especially the AllGraphQLCases type. It contains integration testing that starts the associated server, then connect to it.
  • graphql-maven-plugin-samples-Forum-server. This project is a GraphQL API to manage a simple forum. It embeds an in memory database, that is filled at startup time with simulated data. This data is also used in the integration tests in the client, see below. It contains a sample for Custom Scalar and for Schema personalization (you can change the generated objects through a personalization file). The server is package as a Spring Boot application, and is executed on a http URL.
  • graphql-maven-plugin-samples-Forum-client. Demonstration for Custom Scalar
  • graphql-maven-plugin-samples-StarWars-server. The server is package as a WAR application, and is executed on a https URL.
  • graphql-maven-plugin-samples-StarWars-client. For integration tests, the WAR server is started into a tomcat, and exposed as an https URL.

HowTo compile


Lombok is an excellent tool that generated getters, setters, construtors (and mode) from one annotation.

The plugin uses it a lot, to make the code lighter and easier to read.

You need to install lombok, for your favorite IDE:

Note: The generated code doesn't use Lombok.

Compile the samples

The project should have been imported into your IDE.

If not, check why your IDE didn't properly import a multi-module Maven project.

If you properly configured Lombok (see here above), everything should compile, out of the samples.

To compile the samples (at least with eclipse), you need to add the generated code in the build path, as the project code uses it.

  • Start with a full build (mvn clean install), to be sure all modules are Ok, then:
  • For eclipse:
    • Open the Project explorer view,
    • Navigate to the target folder of the sample you want to compile,
    • right click on the target/generated-sources/graphql-maven-plugin folder,
    • Choose Build Path / USe to Source Folder.
    • Alternatively, you can open the project properties, and update directly the Build Path there.
    • Note: if you compile the project from a terminal window (outside eclipse), and eclipse is configure to refresh the project "with native hooks", it can happen that eclipse interferes with the build. This generates strange bugs when building the plugin-logic module. You'll then have to deactivate the automatic build (menu Project / Build Automaticaly) during the external build
  • For other IDE: please fork the project on github, and provide a Pull Request with the relevant doc.

Help for debugging

View server output

To avoid polluting the maven output, the default log configuration file sent all the output into the log file. You can check that in the /src/main/resources/logback.xml file.

Another file is available, that shows more information, and output it on the console: /src/main/resources/logback-local.xml

To have all the output in the console (very useful when testing), you can start the GraphQLServerMain with this JVM parameter:

GraphQLServerMain -Dlogging.config=classpath:logback-local.xml