Unable to map post response Angular 7

Question

I am trying to setup a service on Angular version 7 but I'm having an issue on res.json() which throws the error Property 'json' does not exist on type 'Object'. This is my service's code:

import {Injectable} from '@angular/core';
import {HttpClient} from '@angular/common/http';
import {Observable} from "rxjs";
import 'rxjs/add/operator/map';
import { map } from 'rxjs/operators';

import {
    SVCParameters,
    SVCResult
} from "./types";

const SERVER_URL: string = 'api/';

@Injectable()
export class IrisService {

    constructor(private http: HttpClient) {
    }

    public trainModel(svcParameters: SVCParameters): Observable<SVCResult> {
        return this.http.post(`${SERVER_URL}train`, svcParameters).pipe(map(res => res.json()));

    }
}

The following is my types.ts code:

export class SVCParameters {
C: number = 2.0;
}

export class SVCResult{
accuracy: number;
}

Possible duplicate of [Property 'json' does not exist on type 'Object'](https://stackoverflow.com/questions/46005430/property-json-does-not-exist-on-type-object) — Jota.Toledo, Mar 06 '19 at 09:21
In the new HttpClient (Angular 4.3+), the response object is JSON by default, so you don't need to do response.json() anymore. Just use response directly — Jaykant, Mar 06 '19 at 09:27

score 0 · Accepted Answer · answered Mar 06 '19 at 09:19

0

Angular 7 HttpClientModule, by default returns response as JSON, there's no need to map the response as res.json() just remove your pipe operator. Everything will work fine.

import {Injectable} from '@angular/core';
import {HttpClient} from '@angular/common/http';
import {Observable} from "rxjs";
import 'rxjs/add/operator/map';
import { map } from 'rxjs/operators';

import {
    SVCParameters,
    SVCResult
} from "./types";

const SERVER_URL: string = 'api/';

@Injectable()
export class IrisService {

    constructor(private http: HttpClient) {
    }

    public trainModel(svcParameters: SVCParameters): Observable<SVCResult> {
        return this.http.post(`${SERVER_URL}train`, svcParameters);

    }
}

answered Mar 06 '19 at 09:19

Nithya Rajan

4,722
19
30

I get the following error instead: Type 'Observable – Christopher Kinyua Mar 06 '19 at 09:27
try `any`, if everything works fine, then try to figure out which type is suited and whether the response has all the properties of the type or not. – Nithya Rajan Mar 06 '19 at 09:30
1

I've replaced 'Observable' with 'any' and the error is gone. I really hope this is what I'm supposed to do because I'm just learning Angular. – Christopher Kinyua Mar 06 '19 at 09:41
@ChristopherKinyua its not – Jota.Toledo Mar 06 '19 at 11:02

Unable to map post response Angular 7

1 Answers1