2.2.7. Registering Protobuf schemas with Data Grid Server

Prerequisites

• Generate Protobuf schema with the ProtoStream processor.

  You can find generated Protobuf schema in the target/<schemaFilePath>/ directory.

• Have a user with CREATE permissions.

  참고

  Security authorization requires CREATE permissions to add schemas. With the default settings, you need the deployer role at minimum.

• Open the Data Grid Console in any browser, select the Schema tab and then Add Protobuf schema.

• Use the schema command with the --upload= argument from the Data Grid command line interface (CLI).

  schema --upload=person.proto person

• Include the Protobuf schema in the payload of a POST request with the REST API.

  POST/rest/v2/schemas/<schema_name>

• Use the generated SerializationContextInitializer implementation with a Hot Rod client to register the Protobuf schema, as in the following example:

  /**
   * Register generated Protobuf schema with Data Grid Server.
   * This requires the RemoteCacheManager to be initialized.
   *
   * @param schema The schema to be registered. Can be a {@link GeneratedSchema } or a programmatic one.
   * See {@link SerializationContextInitialiser}
   */
  private void registerSchemas(Schema schema) {
    RemoteSchemasAdmin schemas = remoteCacheManager.administration().schemas();
    schemas.create(schema);
  
    // Ensure the registered Protobuf schemas do not contain errors.
    // Throw an exception if errors exist.
    Optional<String> error = schemas.retrieveError(schema.getName())
    if (error.isPresent()) {
      throw new IllegalStateException("The schema contains an error: " + error.get() + "\nSchema :\n" + schema.getName());
    }
  }

• Add a JAR file with the SerializationContextInitializer implementation and custom classes to the $RHDG_HOME/server/lib directory.

  When you do this, Data Grid Server registers your Protobuf schema at startup. However, you must add the archive to each server installation because the schema are not saved in the ___protobuf_metadata cache or automatically distributed across the cluster.

  참고

  You must do this if you require Data Grid Server to perform any application/x-protostream to application/x-java-object conversions, in which case you must also add any JAR files for your POJOs.