title: Angular - HttpClient: Map Get method object result to array property
body: <p>I am calling an API that returns a JSON Object.  I need just the value of the array to map to a Observable .  If I call api that just returns the array my service call works.</p>
  
  <p>Below is my sample code  ..   </p>
  
  <pre><code>// my service call ..
  import { Injectable } from '@angular/core';
  import {Observable} from 'rxjs/Observable';
  import {Show} from '../models/show';
  import {HttpClient} from '@angular/common/http';
  
  @Injectable()
  export class MyService {
  
    constructor(private http: HttpClient ) { }
  
  
    findAllShows(): Observable&lt;Show[]&gt; {
      return this.http
        .get&lt;Show[]&gt;(`${someURL}/shows`)
    }
  }
  </code></pre>
  
  <p>If the return is a JSON Object such as below this fails.. </p>
  
  <pre><code>// Service API that FAILS ...
  {
    "shows": [
      {
        "id": "123f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-13 15:54:47",
        "name": "Main Show1"
      },
      {
        "id": "456f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-14 15:54:47",
        "name": "Main Show2"
      },
      {
        "id": "789f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-17 15:54:47",
        "name": "Main Show3"
      }
    ]
  }
  </code></pre>
  
  <p>Now this one works if I just return the Array </p>
  
  <pre><code>// Service API that Works ...
  [
      {
        "id": "123f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-13 15:54:47",
        "name": "Main Show1"
      },
      {
        "id": "456f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-14 15:54:47",
        "name": "Main Show2"
      },
      {
       "id": "789f9165-80a2-41d8-997a-aecc0bfb2e22",
        "modified": "2017-08-17 15:54:47",
        "name": "Main Show3"
      }
    ]
  </code></pre>
  
  <p>How do I map the JSON object Observable into an Array Observable???</p>