Quick Start - Java

This guide gets you started with SymphonyQL with a simple working example on Java.

Assuming we want to develop an application for the GraphQL Schema below:

schema {
  query: Queries
}

enum Origin {
  EARTH
  MARS
  BELT
}

type CharacterOutput {
  name: String!
  origin: Origin!
}

type Queries {
  characters(origin: Origin): [CharacterOutput!]
}

SymphonyQL uses APT (Annotation Processing Tool) to automatically generate schema during compilation. Therefore, you only need to write record class to define the schema:

Defining Resolver

Resolver Object defined using @ObjectSchema:

@ObjectSchema
record Queries(Function<FilterArgs, Source<CharacterOutput, NotUsed>> characters) {
}

FilterArgs is the input and Source<CharacterOutput, NotUsed>> is the output. Source indicates that it is a Query/Subscription that returns pekko streams. For more types, please refer to the Schema Specification.

Defining Object

Object defined using @ObjectSchema:

@ObjectSchema
record CharacterOutput(String name, Origin origin) {
}

Defining Input

Input defined using @InputSchema and @ArgExtractor:

@InputSchema
@ArgExtractor
record FilterArgs(Optional<Origin> origin, Optional<NestedArg> nestedArg) {
}

Defining Enum

Enum defined using @EnumSchema, if the enumeration is input, you also need @ArgExtractor:

@EnumSchema
@ArgExtractor
enum Origin {
  EARTH,
  MARS,
  BELT
}

After writing the record class, we don't need to write graphql schemas to start developing the application.

Let's start developing the application now:

var graphql = SymphonyQL
        .newSymphonyQL()
        .addQuery(
                new Queries(
                        args1 -> Source.single(new CharacterOutput("hello-" + args1.origin().map(Enum::toString).get(), args1.origin().get()))
                ),
                QueriesSchema.schema
        )
        .build();

var characters = """
          {
          characters(origin: "BELT") {
            name
            origin
          }
        }""";

final var actorSystem = ActorSystem.create("symphonyActorSystem");

var getRes = graphql.run(
        SymphonyQLRequest.newRequest().query(Optional.of(characters)).build(),
        actorSystem
);

QueriesSchema.schema is a static method automatically generated by APT.

Fast integration into pekko-http applications

Also see Scala