Consuming GraphQL API in Spring Boot controller

Question

I need to consume graphQL API provided by third party inside my Spring Boot controller, I tried as mentioned here but getting 400 error. Below is the code:

@SuppressWarnings("unchecked")
@RequestMapping(value = "/graphQLTest")
public ResponseEntity<?> testGraphQL() throws JsonProcessingException {

    CloseableHttpClient client= null;
    CloseableHttpResponse response= null;

    client= HttpClients.createDefault();
    HttpPost httpPost= new HttpPost("http://172.30.66.149:3000/graphql");

    httpPost.addHeader("Accept","application/json");

    try {
        StringEntity entity= new StringEntity("{\"query\":\"{hello}\"}");

        httpPost.setEntity(entity);
        response= client.execute(httpPost);
        System.out.println("response: "+response);
    }

    catch(UnsupportedEncodingException e){
        e.printStackTrace();
    }
    catch(ClientProtocolException e){
        e.printStackTrace();
    }
    catch(IOException e){
        e.printStackTrace();
    }

    return null;
}

When I tried to call same URL in Postman I get the response, below is the screenshot:

But when I try it in my controller, I get below error, Can anyone help me out how can I consume someone's GraphQL API .

Error: HttpResponseProxy{HTTP/1.1 400 Bad Request [X-Powered-By: Express, Content-Type: application/json; charset=utf-8, Content-Length: 53, ETag: W/"35-1vperDe+r7EpHry/i+J3wg", Date: Tue, 24 Apr 2018 12:32:52 GMT, Connection: keep-alive] ResponseEntityProxy{[Content-Type: application/json; charset=utf-8,Content-Length: 53,Chunked: false]}}

Answer 1

I just tried to call my graphQL API through jersey api as below and I was able to get the response.

@SuppressWarnings("unchecked")
@RequestMapping(value = "/graphQLTest")
public ResponseEntity<?> testGraphQL() throws JsonProcessingException {

    JSONObject jsonObj = new JSONObject();     
    jsonObj.put("query", "{\n" + 
        "  hello\n" + 
        "}");

    Client client = Client.create();
    String URL = "http://172.30.66.149:3000";
    WebResource webResource = client.resource(URL);

    ClientResponse response = webResource.type("application/json").accept("application/json").post(ClientResponse.class, jsonObj.toString());
    String output = response.getEntity(String.class);
    System.out.println(output);

    return null;
}

Is there any alternate way to make this call, or specifically graphQL way?