title: Angular Service subscribe not allowed in component
body: <p>I have a service that's returning some code:</p>
  
  <p>Here is the code for the service and for the component:</p>
  
  <p>Code in service:</p>
  
  <pre><code>async readdir() {
      try {
        const ret = await Filesystem.readdir({
          path: '',
          directory: FilesystemDirectory.Documents
        });
        return ret;
      } catch (e) {
        console.error('Unable to read dir', e);
      }
    }
  </code></pre>
  
  <p>Code in Component</p>
  
  <pre><code>getdirdata() {
      this.filesystemService.readdir().subscribe(data =&gt; {
        console.log(data);
      });
    }
  </code></pre>
  
  <p>My issue is that it doesn't like subscribe...</p>
  
  <p>I get: </p>
  
  <pre><code>Property 'subscribe' does not exist on type 'Promise&lt;ReaddirResult[]&gt;'.
  </code></pre>
  
  <p>How can I fix this?</p>