graphql:generateServerCode

Full name:

com.graphql-java-generator:graphql-maven-plugin:2.5:generateServerCode

Description:

The generateServerCode Maven goal (and Gradle task) generates the java code for an almost ready to start GraphQL server. The developer has only to develop request to the data.

The java code is generated from one or more GraphQL schemas. It allows to work in Java with graphQL, in a schema first approach. These items are generated:

  • the main method (in a jar project) or the main servlet (in a war project)
  • All the GraphQL wiring, based on graphql-java-spring, itself being build on top of graphql-java
  • All the POJOs, that contain the incoming request contents. The request response is written by the user code into these POJO, and the plugin take care of mapping them into the server response.
  • An option allows to annotate the POJOs with the standard JPA annotations, to make it easy to link with a database. Please note that a
  • All the interfaces for the com.graphql_java_generator.plugin.language.DataFetchersDelegate (named providers in the graphql.org presentation) that the server needs to implement

The specific code that needs to be implemented is the access to the Data: your database, other APIs or web services, or any kind of storage you may have. This is done by implementing the interfaces for the com.graphql_java_generator.plugin.language.DataFetchersDelegate into a Spring component, that is:

  • Create a class for each generated com.graphql_java_generator.plugin.language.DataFetchersDelegate interface
  • Make it implement the relevant com.graphql_java_generator.plugin.language.DataFetchersDelegate interface
  • Mark it with the org.springframework.stereotype.Component annotation

And you're done! :)

You'll find more info in the tutorials: take a look at the Maven server tutorial or the Gradle server tutorial

Attributes:

  • Requires a Maven project to be executed.
  • The goal is not marked as thread-safe and thus does not support parallel builds.
  • Binds by default to the lifecycle phase: generate-sources.

Optional Parameters

Name Type Since Description
<addRelayConnections> boolean -

True if the plugin is configured to add the Relay connection capabilities to the field marked by the @RelayConnection directive.

If so, the plugin reads the provided GraphQL schema file(s), and enriches them with the interfaces and types needed to respect the Relay Connection specification. The entry point for that is the @RelayConnection directive.

You'll find all the information on the plugin web site. Please check the server Relay capability page.


Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.addRelayConnections.
<copyRuntimeSources> boolean -

Flag to enable (or not) the copy of the sources from the graphql-java-runtime library to target source code directory. That is: it allows to control whether the runtime code is embedded in the generated code or not.

Caution: the default value changed since the 2.0 version. In 1.x version, the default value is true. Since 2.0 version, the default value is false.

  • If copyRuntimeSources=true: the runtime is copied along with the generated code. The project configuration (pom.xml or build.gradle) must contain the com.graphql-java-generator:graphql-java-dependencies dependency, with the same version as the GraphQL plugin
  • If copyRuntimeSources=false: the runtime is NOT copied along with the generated code. The project configuration (pom.xml or build.gradle) must contain the com.graphql-java-generator:graphql-java-runtime dependency, with the same version as the GraphQL plugin

Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.copyRuntimeSources.
<customScalars> List<CustomScalarDefinition> -

This parameter contains the list of custom scalars implementations. One such implementation must be provided for each custom scalar defined in the GraphQL implemented by the project for its GraphQL schema. It's a list, where the key is the scalar name, as defined in the GraphQL schema, and the value is the full class name of the implementation of graphql.schema.GraphQLScalarType.

This parameter is a list of customScalars. For each one, you must define the name, the javaType and exactly one of these fields: graphQLScalarTypeClass, graphQLScalarTypeStaticField or graphQLScalarTypeGetter.

Here is the detail:

  • graphQLTypeName: The type name, as defined in the GraphQL schema, for instance Date
  • javaType: The full class name for the java type that contains the data for this type, once in the Java code, for instance java.util.Date
  • graphQLScalarTypeClass: The full class name for the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. This class must be a subtype of graphql.schema.GraphQLScalarType. Bu the constructor of graphql.schema.GraphQLScalarType has been deprecated, so you'll find no sample for that in this project
  • graphQLScalarTypeStaticField: The full class name followed by the static field name that contains the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. For instance, the graphql-java package provides several custom scalars like graphql.Scalars.GraphQLLong. You can also use the graphql-java-extended-scalars project, that provides other custom scalars like graphql.scalars.ExtendedScalars.NonNegativeInt.
  • graphQLScalarTypeGetter: The full class name followed by the static method name that returns the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. For instance: org.mycompany.MyScalars.getGraphQLLong() or com.graphql_java_generator.customscalars.GraphQLScalarTypeDate. This call may contain parameters, provided that this a valid java command.

Please have a look at the allGraphQLCases (both client and server) samples for more information. The allGraphQLCases client pom is a good sample.


User property is: com.graphql_java_generator.mavenplugin.customScalars.
<enumPrefix> String - An optional prefix to add to the classnames of the generated java classes for GraphQL enums. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.enumPrefix.
<enumSuffix> String - An optional suffix to add to the classnames of the generated java classes for GraphQL enums. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.enumSuffix.
<generateBatchLoaderEnvironment> boolean -

(only for server mode) Indicates if the plugin should generate add the org.dataloader.BatchLoaderEnvironment parameter to the batchLoader methods, in DataFetchersDelegate. This parameter allows to get the context of the Batch Loader, including the context associated to the id, when using the id has been added by the org.dataloader.DataLoader.load(java.lang.Object,java.lang.Object) method.

For instance, if you have the method below, for a field named oneWithIdSubType in a DataFetcherDelegate:

@Override
public CompletableFuture<AllFieldCasesWithIdSubtype> oneWithIdSubType(
		DataFetchingEnvironment dataFetchingEnvironment, DataLoader<UUID, AllFieldCasesWithIdSubtype> dataLoader,
		AllFieldCases source, Boolean uppercase) {
	return dataLoader.load(UUID.randomUUID());
}

then, in the AllFieldCasesWithIdSubtype DataFetcherDelegate, you can retrieve the uppercase this way:

@Override
public List<AllFieldCasesWithIdSubtype> batchLoader(List<UUID> keys, BatchLoaderEnvironment environment) {
	List<AllFieldCasesWithIdSubtype> list = new ArrayList<>(keys.size());
	for (UUID id : keys) {
		// Let's manage the uppercase parameter, that was associated with this key
		Boolean uppercase = (Boolean) environment.getKeyContexts().get(id);
		if (uppercase != null && uppercase) {
			item.setName(item.getName().toUpperCase());
		}

		// Do something with the id and the uppercase value
	}
	return list;
}

For more complex cases, you can store a java.util.Map with all the needed values, instead of just the parameter value.

The default value changed since 2.0 version: it is false in 1.x version, and true since the 2.0 version


Default value is: true.
User property is: com.graphql_java_generator.mavenplugin.generateBatchLoaderEnvironment.
<generateDataFetcherForEveryFieldsWithArguments> boolean -

(only for server mode, since 2.5) Defines if a data fetcher is needed for every GraphQL field that has input argument, and add them in the generated POJOs. This allows a better compatibility with spring-graphql, and an easy access to the field's parameters.

With this argument to false, the data fetchers are generated only for field which type is a type (not a scalar or an enum), and for the query, mutation and subscription types.

With this argument to true, the data fetchers are generated for all GraphQL fields which type is a type (not a scalar or an enum) or that has one or arguments

This parameter is available since version 2.5. Its default value is false in 2.x versions for backward compatibility with existing implementations based on the plugin. But the recommended value is true.


Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.generateDataFetcherForEveryFieldsWithArguments.
<generateDataLoaderForLists> boolean -

(only for server mode) Defines how the methods in the data fetchers delegates are generated. The detailed information is available in the Wiki server page

When generateDataLoaderForLists is false (default mode), the data loaders are used only for fields that don't return a list. In other words, for fields which type is a sub-object with an id, two methods are generated: one which returns a java.util.concurrent.CompletableFuture, and one which returns a none java.util.concurrent.CompletableFuture result (that is used by the generated code only if no data loader is available).

When generateDataLoaderForLists is true, the above behavior is extended to fields that are a list.

Note: if set to true, this plugin parameter make the use of data loader mandatory for every field which type is a list of GraphQL objects, which have an id. This may not be suitable, for instance when your data is stored in a relational database, where you would need a first query to retrieve the ids and push them into the data loader, then another one to retrieve the associated values. If you want to use data loader for only some of particular fields, you should consider using the generateDataLoaderForLists. You'll find more information on the Wiki server page.

This parameter is available since version 1.18.4


Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.generateDataLoaderForLists.
<generateJPAAnnotation> boolean -

(only for server mode) Indicates whether the plugin should generate the JPA annotations, for generated objects.

Note: if the generated code must be used with Spring 3, you must set the useJakartaEE9 plugin parameter to true.

Default value is false


Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.generateJPAAnnotation.
<inputPrefix> String - An optional prefix to add to the classnames of the generated java classes for GraphQL input objects. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.inputPrefix.
<inputSuffix> String - An optional suffix to add to the classnames of the generated java classes for GraphQL input objects. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.javaClassSuffix.
<interfacePrefix> String - An optional prefix to add to the classnames of the generated java classes for GraphQL interfaces. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.interfacePrefix.
<interfaceSuffix> String - An optional suffix to add to the classnames of the generated java classes for GraphQL interfaces. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.interfaceSuffix.
<javaTypeForIDType> String -

The javaTypeForIDType is the java class that is used in the generated code for GraphQL fields that are of the GraphQL ID type. The default value is java.util.UUID. Valid values are: java.lang.String, java.lang.Long and java.util.UUID.

This parameter is only valid for the server mode. When generating the client code, the ID is always generated as a String type, as recommended in the GraphQL doc.

In other words: when in server mode and javaTypeForIDType is not set, all GraphQL ID fields are UUID attributes in java. When in server mode and javaTypeForIDType is set to the X type, all GraphQL ID fields are X attributes in java.

Note: you can override this, by using the schema personalization capability. For more information, please have a look at the Schema Personalization doc page.


Default value is: java.util.UUID.
User property is: com.graphql_java_generator.mavenplugin.javaTypeForIDType.
<maxTokens> Integer - (Useless, since 1.18.7)Defines the options that maximum number of tokens that the GraphQL schema parser may read. The default value is Integer.MAX_VALUE (=2147483647). If the schema contains more than maxTokens, the build will fail with an error.
Default value is: 2147483647.
User property is: com.graphql_java_generator.mavenplugin.maxTokens.
<packageName> String - The package name that will contain the generated classes
Default value is: com.generated.graphql.
User property is: com.graphql_java_generator.mavenplugin.packageName.
<queryMutationExecutionProtocol> QueryMutationExecutionProtocol - (since 2.0RC1) The com.graphql_java_generator.plugin.conf.QueryMutationExecutionProtocol to use for GraphQL queries and mutations (not subscriptions). The allowed values are: http and webSocket.
The default value is http.
Default value is: http.
User property is: com.graphql_java_generator.mavenplugin.queryMutationExecutionProtocol.
<scanBasePackages> String -

(only for server mode) A comma separated list of package names, without double quotes, that will also be parsed by Spring, to discover Spring beans, Spring repositories and JPA entities when the server starts. You should use this parameter only for packages that are not subpackage of the package defined in the _packageName_ parameter and not subpackage of com.graphql_java_generator

This allows for instance, to set packageName to your.app.package.graphql, and to define your Spring beans, like the DataFetcherDelegates or your Spring data repositories in any other folder, by setting for instance scanBasePackages to your.app.package.impl, your.app.package.graphql, or just your.app.package


Default value is: null.
User property is: com.graphql_java_generator.mavenplugin.scanBasePackages.
<schemaFileFolder> File - The folder where the graphql schema file(s) will be searched. The default schema is the main resource folder.
Default value is: src/main/resources.
User property is: com.graphql_java_generator.mavenplugin.schemaFileFolder.
<schemaFilePattern> String -

The pattern to find the graphql schema file(s). The default value is "/*.graphqls" meaning that the maven plugin will search all graphqls files in the "/src/main/resources" folder (please check also the schemaFileFolder plugin parameter).

You can put the star (*) joker in the filename, to retrieve several files at ones, for instance /myschema*.graphqls will retrieve the /src/main/resources/myschema.graphqls and /src/main/resources/myschema_extend.graphqls files.


Default value is: *.graphqls.
User property is: com.graphql_java_generator.mavenplugin.schemaFilePattern.
<schemaPersonalizationFile> String -

schemaPersonalizationFile is the file name where the GraphQL maven plugin will find personalization that it must apply before generating the code. Since the 2.2 release, it is available for both client and server. Before, it applies to the server mode only.

This allows to:

  • Add or modify fields
  • Add interface and annotation to classes (GraphQL types, input types, interfaces, unions and enums) or fields.

See the doc on the project's wiki for more details.


Default value is: null.
User property is: com.graphql_java_generator.mavenplugin.schemaPersonalizationFile.
<separateUtilityClasses> boolean -

Indicates whether the utility classes (that is: the classes that are not match an item in the GraphQL schema) are generated in the same package than the classes that matches the GraphQL schema.

The classes that map the GraphQL schema (type, input type, interfaces, unions...) are generated in the package defined in the packageName plugin parameter, then:

  • If false (default for versions 1.x), the utility classes are generated in the the same package
  • If true (default for version 2.0 and after), the utility classes are generated in the util subpackage of this package

Default value is: true.
User property is: com.graphql_java_generator.mavenplugin.separateUtilityClasses.
<skipGenerationIfSchemaHasNotChanged> boolean -

This parameter is now deprecated: it's value used in the plugin is always true, that is: if the generated sources or resources are older than the GraphQL schema file(s), then there is no source or resource generation. In clear, the source and resource generation is executed only if the provided input (GraphQL schema...) has been updated since the last plugin execution.


Default value is: true.
User property is: com.graphql_java_generator.mavenplugin.skipGenerationIfSchemaHasNotChanged.
<sourceEncoding> String - The encoding charset for the generated source files
Default value is: UTF-8.
User property is: com.graphql_java_generator.mavenplugin.sourceEncoding.
<springBeanSuffix> String - Retrieves the suffix that will be applied to the name of the Spring Beans that are generated for this schema. It's mandatory if you' using a Spring app and have more than one GraphQL schemas. The default value is an empty String.
User property is: com.graphql_java_generator.mavenplugin.springBeanSuffix.
<targetResourceFolder> File - The folder where resources will be generated
Default value is: ./target/generated-resources/graphql-maven-plugin.
User property is: com.graphql_java_generator.mavenplugin.targetResourceFolder.
<targetSourceFolder> File - The folder where source code for the generated classes will be generated
Default value is: ./target/generated-sources/graphql-maven-plugin.
User property is: com.graphql_java_generator.mavenplugin.targetSourceFolder.
<templates> Map<String,String> -

Map of the code templates to be used: this allows to override the default templates, and control exactly what code is generated by the plugin.

You can override any of the Velocity templates of the project. The list of templates is defined in the enum CodeTemplate, that you can check here.

You can find a sample in the CustomTemplates client sample.

Important notice: Please note that the default templates may change in the future. And some of these modifications would need to be reported into the custom templates. We'll try to better expose a stable public API in the future.


User property is: com.graphql_java_generator.mavenplugin.templates.
<typePrefix> String - An optional prefix to add to the classnames of the generated java classes for GraphQL types. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.typePrefix.
<typeSuffix> String - An optional suffix to add to the classnames of the generated java classes for GraphQL types. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.typeSuffix.
<unionPrefix> String - An optional prefix to add to the classnames of the generated java classes for GraphQL unions. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.unionPrefix.
<unionSuffix> String - An optional suffix to add to the classnames of the generated java classes for GraphQL unions. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
User property is: com.graphql_java_generator.mavenplugin.unionSuffix.
<useJakartaEE9> boolean - (since 2.0RC1) If false, it uses jakarta EE8 imports (that begins by javax.). If true, it uses jakarta EE8 imports (that begins by jakarta.).
Default value is: false.
User property is: com.graphql_java_generator.mavenplugin.useJakartaEE9.

Parameter Details

<addRelayConnections>

True if the plugin is configured to add the Relay connection capabilities to the field marked by the @RelayConnection directive.

If so, the plugin reads the provided GraphQL schema file(s), and enriches them with the interfaces and types needed to respect the Relay Connection specification. The entry point for that is the @RelayConnection directive.

You'll find all the information on the plugin web site. Please check the server Relay capability page.

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.addRelayConnections
  • Default: false

<copyRuntimeSources>

Flag to enable (or not) the copy of the sources from the graphql-java-runtime library to target source code directory. That is: it allows to control whether the runtime code is embedded in the generated code or not.

Caution: the default value changed since the 2.0 version. In 1.x version, the default value is true. Since 2.0 version, the default value is false.

  • If copyRuntimeSources=true: the runtime is copied along with the generated code. The project configuration (pom.xml or build.gradle) must contain the com.graphql-java-generator:graphql-java-dependencies dependency, with the same version as the GraphQL plugin
  • If copyRuntimeSources=false: the runtime is NOT copied along with the generated code. The project configuration (pom.xml or build.gradle) must contain the com.graphql-java-generator:graphql-java-runtime dependency, with the same version as the GraphQL plugin
  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.copyRuntimeSources
  • Default: false

<customScalars>

This parameter contains the list of custom scalars implementations. One such implementation must be provided for each custom scalar defined in the GraphQL implemented by the project for its GraphQL schema. It's a list, where the key is the scalar name, as defined in the GraphQL schema, and the value is the full class name of the implementation of graphql.schema.GraphQLScalarType.

This parameter is a list of customScalars. For each one, you must define the name, the javaType and exactly one of these fields: graphQLScalarTypeClass, graphQLScalarTypeStaticField or graphQLScalarTypeGetter.

Here is the detail:

  • graphQLTypeName: The type name, as defined in the GraphQL schema, for instance Date
  • javaType: The full class name for the java type that contains the data for this type, once in the Java code, for instance java.util.Date
  • graphQLScalarTypeClass: The full class name for the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. This class must be a subtype of graphql.schema.GraphQLScalarType. Bu the constructor of graphql.schema.GraphQLScalarType has been deprecated, so you'll find no sample for that in this project
  • graphQLScalarTypeStaticField: The full class name followed by the static field name that contains the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. For instance, the graphql-java package provides several custom scalars like graphql.Scalars.GraphQLLong. You can also use the graphql-java-extended-scalars project, that provides other custom scalars like graphql.scalars.ExtendedScalars.NonNegativeInt.
  • graphQLScalarTypeGetter: The full class name followed by the static method name that returns the graphql.schema.GraphQLScalarType that will manage this Custom Scalar. For instance: org.mycompany.MyScalars.getGraphQLLong() or com.graphql_java_generator.customscalars.GraphQLScalarTypeDate. This call may contain parameters, provided that this a valid java command.

Please have a look at the allGraphQLCases (both client and server) samples for more information. The allGraphQLCases client pom is a good sample.

  • Type: java.util.List<com.graphql_java_generator.plugin.conf.CustomScalarDefinition>
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.customScalars

<enumPrefix>

An optional prefix to add to the classnames of the generated java classes for GraphQL enums. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.enumPrefix

<enumSuffix>

An optional suffix to add to the classnames of the generated java classes for GraphQL enums. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.enumSuffix

<generateBatchLoaderEnvironment>

(only for server mode) Indicates if the plugin should generate add the org.dataloader.BatchLoaderEnvironment parameter to the batchLoader methods, in DataFetchersDelegate. This parameter allows to get the context of the Batch Loader, including the context associated to the id, when using the id has been added by the org.dataloader.DataLoader.load(java.lang.Object,java.lang.Object) method.

For instance, if you have the method below, for a field named oneWithIdSubType in a DataFetcherDelegate:

@Override
public CompletableFuture<AllFieldCasesWithIdSubtype> oneWithIdSubType(
		DataFetchingEnvironment dataFetchingEnvironment, DataLoader<UUID, AllFieldCasesWithIdSubtype> dataLoader,
		AllFieldCases source, Boolean uppercase) {
	return dataLoader.load(UUID.randomUUID());
}

then, in the AllFieldCasesWithIdSubtype DataFetcherDelegate, you can retrieve the uppercase this way:

@Override
public List<AllFieldCasesWithIdSubtype> batchLoader(List<UUID> keys, BatchLoaderEnvironment environment) {
	List<AllFieldCasesWithIdSubtype> list = new ArrayList<>(keys.size());
	for (UUID id : keys) {
		// Let's manage the uppercase parameter, that was associated with this key
		Boolean uppercase = (Boolean) environment.getKeyContexts().get(id);
		if (uppercase != null && uppercase) {
			item.setName(item.getName().toUpperCase());
		}

		// Do something with the id and the uppercase value
	}
	return list;
}

For more complex cases, you can store a java.util.Map with all the needed values, instead of just the parameter value.

The default value changed since 2.0 version: it is false in 1.x version, and true since the 2.0 version

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.generateBatchLoaderEnvironment
  • Default: true

<generateDataFetcherForEveryFieldsWithArguments>

(only for server mode, since 2.5) Defines if a data fetcher is needed for every GraphQL field that has input argument, and add them in the generated POJOs. This allows a better compatibility with spring-graphql, and an easy access to the field's parameters.

With this argument to false, the data fetchers are generated only for field which type is a type (not a scalar or an enum), and for the query, mutation and subscription types.

With this argument to true, the data fetchers are generated for all GraphQL fields which type is a type (not a scalar or an enum) or that has one or arguments

This parameter is available since version 2.5. Its default value is false in 2.x versions for backward compatibility with existing implementations based on the plugin. But the recommended value is true.

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.generateDataFetcherForEveryFieldsWithArguments
  • Default: false

<generateDataLoaderForLists>

(only for server mode) Defines how the methods in the data fetchers delegates are generated. The detailed information is available in the Wiki server page

When generateDataLoaderForLists is false (default mode), the data loaders are used only for fields that don't return a list. In other words, for fields which type is a sub-object with an id, two methods are generated: one which returns a java.util.concurrent.CompletableFuture, and one which returns a none java.util.concurrent.CompletableFuture result (that is used by the generated code only if no data loader is available).

When generateDataLoaderForLists is true, the above behavior is extended to fields that are a list.

Note: if set to true, this plugin parameter make the use of data loader mandatory for every field which type is a list of GraphQL objects, which have an id. This may not be suitable, for instance when your data is stored in a relational database, where you would need a first query to retrieve the ids and push them into the data loader, then another one to retrieve the associated values. If you want to use data loader for only some of particular fields, you should consider using the generateDataLoaderForLists. You'll find more information on the Wiki server page.

This parameter is available since version 1.18.4

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.generateDataLoaderForLists
  • Default: false

<generateJPAAnnotation>

(only for server mode) Indicates whether the plugin should generate the JPA annotations, for generated objects.

Note: if the generated code must be used with Spring 3, you must set the useJakartaEE9 plugin parameter to true.

Default value is false

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.generateJPAAnnotation
  • Default: false

<inputPrefix>

An optional prefix to add to the classnames of the generated java classes for GraphQL input objects. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.inputPrefix

<inputSuffix>

An optional suffix to add to the classnames of the generated java classes for GraphQL input objects. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.javaClassSuffix

<interfacePrefix>

An optional prefix to add to the classnames of the generated java classes for GraphQL interfaces. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.interfacePrefix

<interfaceSuffix>

An optional suffix to add to the classnames of the generated java classes for GraphQL interfaces. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.interfaceSuffix

<javaTypeForIDType>

The javaTypeForIDType is the java class that is used in the generated code for GraphQL fields that are of the GraphQL ID type. The default value is java.util.UUID. Valid values are: java.lang.String, java.lang.Long and java.util.UUID.

This parameter is only valid for the server mode. When generating the client code, the ID is always generated as a String type, as recommended in the GraphQL doc.

In other words: when in server mode and javaTypeForIDType is not set, all GraphQL ID fields are UUID attributes in java. When in server mode and javaTypeForIDType is set to the X type, all GraphQL ID fields are X attributes in java.

Note: you can override this, by using the schema personalization capability. For more information, please have a look at the Schema Personalization doc page.

  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.javaTypeForIDType
  • Default: java.util.UUID

<maxTokens>

(Useless, since 1.18.7)Defines the options that maximum number of tokens that the GraphQL schema parser may read. The default value is Integer.MAX_VALUE (=2147483647). If the schema contains more than maxTokens, the build will fail with an error.
  • Type: java.lang.Integer
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.maxTokens
  • Default: 2147483647

<packageName>

The package name that will contain the generated classes
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.packageName
  • Default: com.generated.graphql

<queryMutationExecutionProtocol>

(since 2.0RC1) The com.graphql_java_generator.plugin.conf.QueryMutationExecutionProtocol to use for GraphQL queries and mutations (not subscriptions). The allowed values are: http and webSocket.
The default value is http.
  • Type: com.graphql_java_generator.plugin.conf.QueryMutationExecutionProtocol
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.queryMutationExecutionProtocol
  • Default: http

<scanBasePackages>

(only for server mode) A comma separated list of package names, without double quotes, that will also be parsed by Spring, to discover Spring beans, Spring repositories and JPA entities when the server starts. You should use this parameter only for packages that are not subpackage of the package defined in the _packageName_ parameter and not subpackage of com.graphql_java_generator

This allows for instance, to set packageName to your.app.package.graphql, and to define your Spring beans, like the DataFetcherDelegates or your Spring data repositories in any other folder, by setting for instance scanBasePackages to your.app.package.impl, your.app.package.graphql, or just your.app.package

  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.scanBasePackages
  • Default: null

<schemaFileFolder>

The folder where the graphql schema file(s) will be searched. The default schema is the main resource folder.
  • Type: java.io.File
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.schemaFileFolder
  • Default: src/main/resources

<schemaFilePattern>

The pattern to find the graphql schema file(s). The default value is "/*.graphqls" meaning that the maven plugin will search all graphqls files in the "/src/main/resources" folder (please check also the schemaFileFolder plugin parameter).

You can put the star (*) joker in the filename, to retrieve several files at ones, for instance /myschema*.graphqls will retrieve the /src/main/resources/myschema.graphqls and /src/main/resources/myschema_extend.graphqls files.

  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.schemaFilePattern
  • Default: *.graphqls

<schemaPersonalizationFile>

schemaPersonalizationFile is the file name where the GraphQL maven plugin will find personalization that it must apply before generating the code. Since the 2.2 release, it is available for both client and server. Before, it applies to the server mode only.

This allows to:

  • Add or modify fields
  • Add interface and annotation to classes (GraphQL types, input types, interfaces, unions and enums) or fields.

See the doc on the project's wiki for more details.

  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.schemaPersonalizationFile
  • Default: null

<separateUtilityClasses>

Indicates whether the utility classes (that is: the classes that are not match an item in the GraphQL schema) are generated in the same package than the classes that matches the GraphQL schema.

The classes that map the GraphQL schema (type, input type, interfaces, unions...) are generated in the package defined in the packageName plugin parameter, then:

  • If false (default for versions 1.x), the utility classes are generated in the the same package
  • If true (default for version 2.0 and after), the utility classes are generated in the util subpackage of this package
  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.separateUtilityClasses
  • Default: true

<skipGenerationIfSchemaHasNotChanged>

This parameter is now deprecated: it's value used in the plugin is always true, that is: if the generated sources or resources are older than the GraphQL schema file(s), then there is no source or resource generation. In clear, the source and resource generation is executed only if the provided input (GraphQL schema...) has been updated since the last plugin execution.

  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.skipGenerationIfSchemaHasNotChanged
  • Default: true

<sourceEncoding>

The encoding charset for the generated source files
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.sourceEncoding
  • Default: UTF-8

<springBeanSuffix>

Retrieves the suffix that will be applied to the name of the Spring Beans that are generated for this schema. It's mandatory if you' using a Spring app and have more than one GraphQL schemas. The default value is an empty String.
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.springBeanSuffix

<targetResourceFolder>

The folder where resources will be generated
  • Type: java.io.File
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.targetResourceFolder
  • Default: ./target/generated-resources/graphql-maven-plugin

<targetSourceFolder>

The folder where source code for the generated classes will be generated
  • Type: java.io.File
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.targetSourceFolder
  • Default: ./target/generated-sources/graphql-maven-plugin

<templates>

Map of the code templates to be used: this allows to override the default templates, and control exactly what code is generated by the plugin.

You can override any of the Velocity templates of the project. The list of templates is defined in the enum CodeTemplate, that you can check here.

You can find a sample in the CustomTemplates client sample.

Important notice: Please note that the default templates may change in the future. And some of these modifications would need to be reported into the custom templates. We'll try to better expose a stable public API in the future.

  • Type: java.util.Map<java.lang.String, java.lang.String>
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.templates

<typePrefix>

An optional prefix to add to the classnames of the generated java classes for GraphQL types. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.typePrefix

<typeSuffix>

An optional suffix to add to the classnames of the generated java classes for GraphQL types. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.typeSuffix

<unionPrefix>

An optional prefix to add to the classnames of the generated java classes for GraphQL unions. The prefix is added at the beginning of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.unionPrefix

<unionSuffix>

An optional suffix to add to the classnames of the generated java classes for GraphQL unions. The suffix is added at the end of the java classname, and must be compatible with java naming rules (no space, dot, comma, etc.)
  • Type: java.lang.String
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.unionSuffix

<useJakartaEE9>

(since 2.0RC1) If false, it uses jakarta EE8 imports (that begins by javax.). If true, it uses jakarta EE8 imports (that begins by jakarta.).
  • Type: boolean
  • Required: No
  • User Property: com.graphql_java_generator.mavenplugin.useJakartaEE9
  • Default: false