JHipster spring controller with microservices - spring-boot

Question

I have a JHipster gateway+microservice application. I have added a spring service with jhipster spring-controller and then edited the code like this:
#RestController
#RequestMapping("/api/data")
public class DataResource {
/**
* GET vin
*/
#GetMapping("/vin")
public ResponseEntity<Object> vin(#Valid #RequestBody String address) {
Chart3DataDTO[] data=new Chart3DataDTO[15];
for (int i=0;i<15;i++){
data[i]=new Chart3DataDTO(System.currentTimeMillis()+i, 200+i, 201+i, 202+i);
}
return ResponseEntity.ok(data);
}
For completeness, this is the DTO
public class Chart3DataDTO {
private Long xAxis;
private Integer[] yAxis=new Integer[3];
public Chart3DataDTO(Long xAxis, Integer yAxis1, Integer yAxis2, Integer yAxis3) {
this.xAxis = xAxis;
this.yAxis = new Integer[]{yAxis1, yAxis2, yAxis3};
}
public Long getxAxis() {
return xAxis;
}
public Integer[] getyAxis() {
return yAxis;
}
}
Then I have dockerized gateway and microservice, jhipster docker-compose and started all. Everything works but when the Angular frontent asks for /api/data/vin I get:
if not logged in: 401 (which is fine)
if logged in: the JHipster page 'an error has occurred', instead of returning the JSON of the DTO
What did I miss?
Also, it doesn't appear listed on the Jhipster registry API
2ND EDIT: Added client angular code
import { Injectable } from '#angular/core';
import { Observable, of, throwError } from 'rxjs';
import { HttpClient, HttpHeaders, HttpErrorResponse } from '#angular/common/http';
import { catchError, tap, map } from 'rxjs/operators';
const httpOptions = {
headers: new HttpHeaders({ 'Content-Type': 'application/json',
'Access-Control-Allow-Origin':'*'
})
};
//const apiUrl = 'api/vin';
const apiUrl = '/api/data/vin';
#Injectable({
providedIn: 'root'
})
export class ApiService {
constructor(private http: HttpClient) {}
/*
private handleError<T> (operation = 'operation', result?: T) {
return (error: any): Observable<T> => {
// TODO: send the error to remote logging infrastructure
console.error(error); // log to console instead
// Let the app keep running by returning an empty result.
return of(result as T);
};
}
*/
getInputVoltage(address: String): Observable<[]> {
return this.http.get<[]>(`${apiUrl}` + '?address=' + address,httpOptions);
}
}
And
import { Component, OnInit } from '#angular/core';
import * as Highcharts from 'highcharts';
import { ApiService } from '../api.service';
#Component({
selector: 'jhi-device-graph',
templateUrl: './device-graph.component.html',
styleUrls: ['./device-graph.component.scss']
})
export class DeviceGraphComponent implements OnInit {
Highcharts: typeof Highcharts = Highcharts;
chartOptions: Highcharts.Options = {
xAxis: {
type: 'datetime'
},
yAxis: {
title: {
text: 'Voltage'
}
},
title: {
text: 'Input voltage'
},
series: [
{
data: [
[Date.UTC(2010, 0, 1), 29.9],
[Date.UTC(2010, 2, 1), 71.5],
[Date.UTC(2010, 3, 1), 106.4]
],
type: 'line',
name: 'Vin1'
},
{
data: [
[Date.UTC(2010, 0, 1), 39.9],
[Date.UTC(2010, 2, 1), 91.5],
[Date.UTC(2010, 3, 1), 96.4]
],
type: 'line',
name: 'Vin2'
}
]
};
data: String[] = [];
isLoadingResults = true;
constructor(private api: ApiService) {}
ngOnInit(): void {
this.api.getInputVoltage('10.1.30.1').subscribe(
(res: any) => {
this.data = res;
//console.log(this.data);
this.isLoadingResults = false;
},
err => {
//console.log(err);
this.isLoadingResults = false;
}
);
}
}

Answer 1

Your angular client sends a GET request on /api/data/vin with query parameters while your REST controller expects a request body, this can't work.
Your controller must expect a #RequestParam
Also, as the request goes through a gateway, it must be prefixed by /services and your service name, so in your case the URL is /services/graph/api/data/vin.
Also using #Valid on a String does not do anything unless you add some other validation annotations like #NotBlank or #Size(max=30)
#GetMapping("/vin")
public ResponseEntity<Object> vin(#Valid #RequestParam String address) {
#RequestBody must be used only for POST or PUT.

Answer 2

Assuming you are sending a parameter when you make the get call (seeing that #RequestBody address) and without seeing the logs, you can try changing the ResponseEntity<Object> to ResponseEntity<Chart3DataDTO[]>