静态数据获取程序返回null(GraphQL / Java)

时间:2019-06-20 07:26:44

标签: java graphql-java

我有以下简单的模式/查询示例,其中包含使用Java创建程序化模式的信息。在这里,我正在尝试创建以下架构:

query{
  board {
   name: string
 }
}

代码:

GraphQLObjectType queryType = GraphQLObjectType.newObject()
                .name("BoardQuery")
                .field(GraphQLFieldDefinition.newFieldDefinition()
                        .name("board")
                        .type(GraphQLObjectType.newObject().name("boardType")
                        .field(GraphQLFieldDefinition.newFieldDefinition()
                                .name("name")
                                .type(GraphQLString).build()))

                        .build())

                .build();

        GraphQLCodeRegistry graphQLCodeRegistry = GraphQLCodeRegistry.newCodeRegistry()
                .dataFetcher(FieldCoordinates.coordinates("boardType","name"),
                        new StaticDataFetcher("hello")).build();
        GraphQLSchema graphQLSchema = GraphQLSchema.newSchema()
                .query(queryType)
                .codeRegistry(graphQLCodeRegistry)
                .build();
        GraphQL graphQl = GraphQL.newGraphQL(graphQLSchema).build();
        ExecutionResult executionResult = graphQl.execute("query { board { name } }");
        System.out.println(executionResult.getData().toString());

预期输出:

{name:hello}

实际输出:

{name:null}

我在这里想念东西吗?

1 个答案:

答案 0 :(得分:1)

我本人并不陌生,但是我会给它一个机会。

    //The dataFetcher used to fetch a board object.
    DataFetcher boardDataFetcher() {
        return environment -> {
            Object board = new Object() {
                String name = "board Name";
            };
            return board;
        };
    }
    //Your deffinition of what a board type contains/what of the board type you want to expose
    public GraphQLObjectType boardType = newObject()
            .name("boardType")
            .field(newFieldDefinition()
                    .name("name")
                    .type(GraphQLString)
            )
            .build();
    // Define your query types 
    public GraphQLObjectType queryType = newObject()
            .name("Query")
            .field(newFieldDefinition()
                    .name("board")
                    .type(boardType)
            )
            .build();

    // wire the query, board and datafetcher together
    public GraphQLCodeRegistry codeRegistry = newCodeRegistry()
            .dataFetcher(
                    coordinates("Query", "board"), boardDataFetcher()
            )
            .build();
    //create the schema
    GraphQLSchema graphQLSchema = GraphQLSchema.newSchema()
            .query(queryType)
            .codeRegistry(codeRegistry)
            .build();

这适用于

之类的查询
board{name}

应该给您答复:

"board": {
      "name": "board Name"
    }