title: Can't add user for role/editor user via api in Google Cloud Platform
body: <p>I have been trying to use the api to add user of project editor in Google Cloud Platform.</p>
  
  <p>API I use is <code>Resource Manager API setIampolicy</code>.</p>
  
  <p>To Add user is using Google Apps Script.</p>
  
  <p><strong>PROCEDURE</strong></p>
  
  <ol>
  <li>get current all policy on Google Cloud Platform by using [Resource Manager API getIampolicy].</li>
  <li>add user and fix 1.response json.</li>
  <li>post 2.json using [Resource Manager API setIampolicy].</li>
  </ol>
  
  <p><a href="https://cloud.google.com/resource-manager/reference/rest/v1/projects/getIamPolicy" rel="nofollow noreferrer">https://cloud.google.com/resource-manager/reference/rest/v1/projects/getIamPolicy</a></p>
  
  <p><a href="https://cloud.google.com/resource-manager/reference/rest/v1/projects/setIamPolicy" rel="nofollow noreferrer">https://cloud.google.com/resource-manager/reference/rest/v1/projects/setIamPolicy</a></p>
  
  <p>but, I can't add user.
  With the below Error/Exception:</p>
  
  <pre><code>{
    "error": {
      "code": 400,
      "message": "Request contains an invalid argument.",
      "status": "INVALID_ARGUMENT",
      "details": [
        {
          "@type": "type.googleapis.com/google.cloudresourcemanager.v1.ProjectIamPolicyError",
          "type": "SOLO_REQUIRE_TOS_ACCEPTOR",
          "role": "roles/owner"
        }
      ]
    }
  }
  </code></pre>
  
  <p>Other information 
  I can do by [Try it!] of documents, but can't do by Google Apps Script.</p>
  
  <p>I use OAuth Library of Google Apps Script and OAuth Authentication.</p>
  
  <p>Why?</p>