Polymer iron-ajax POST method not working

Question

I'm learning Polymer. I'm unable to figure the code to "post" using <iron-ajax>. I'm using an online testing API (https://reqres.in/), and I should receive this response back with status code 200:

{"token": "QpwL5tke4Pnpja7X"}".

I couldn't find a tutorial to show a POST example. I have been searching online for the past 24 hours, but everything is about GET and not POST.

If anyone familiar with <iron-ajax> could review my code and help me get it to work or figure out how to write the correct code, it would be very helpful for a beginner like me.

1. Is my code correct with the body property?

2. Is the response the 200 status code or the token?

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   <link rel="import" href="../bower_components/polymer/polymer-element.html">
   <link rel="import" href="shared-styles.html">
   <link rel="import" href="../bower_components/polymer/polymer.html">
   <link rel="import" href="../bower_components/iron-ajax/iron-ajax.html">
   
   <dom-module id="my-view2">
     <!--test using this data: {
         "email": "peter@klaven",
         "password": "cityslicka"
     }-->
     <template>
       <iron-ajax>
           auto 
           method="post"
           url="https://reqres.in/api/login"
           handle-as="json"
           content-type="application/json"
           body =[{"email": "peter@klaven", "password": "cityslicka"}]
           on-response={{handleResponse}}
   
       </iron-ajax>
   
       <!--Handle response-->
       <p> response handling code goes here, how to show the response from the server here?</p>
       <p> It should show: {"token": "QpwL5tke4Pnpja7X"} </p>
       <div>
       <p> {{handleResponse}} </p>
       </div>
     </template>
   
     <script>
       class MyView2 extends Polymer.Element {
         static get is() { return 'my-view2'}; 
   
         static get proporties() {
           return {
             handleResponse: {
               type: Object,
               notify: true,
               readOnly: true 
             }
           };
         }
       }
   
       window.customElements.define(MyView2.is, MyView2);
     </script>
   </dom-module>
   

Answer 1

• Your HTML is malformed (perhaps a copy-paste typo?). The iron-ajax's attributes should be inside the opening tag like this:

  <iron-ajax
    auto
    method="post"
    ...
  >
  </iron-ajax>
  

• You probably meant to bind the handleResponse property to <iron-ajax>.lastResponse, which contains the response to the AJAX request.

  <iron-ajax last-response={{handleResponse}} ...>
  

  Note that the binding of <p>{{handleResponse}}</p> would render the response object as [object Object]. If you want to see the response contents, you'll have to use a computed binding that returns a string (e.g., with JSON.stringify()) like this:

  // <template>
  <p>json(handleResponse)</p>
  
  // <script>
  class XFoo extends Polymer.Element {
    ...
    json(obj) {
      return JSON.stringify(obj);
    }
  }
  

• The attribute value of <iron-ajax>.body should be single-quoted like this:

  <iron-ajax body='[{"foo": "bar"}]'>
  

The full example should look something like this:

<dom-module id="x-foo">
  <template>
    <iron-ajax
              auto
              method="post"
              url="//httpbin.org/post"
              body='[{"foo": "{{foo}}"}]'
              handle-as="json"
              content-type="application/json"
              last-response="{{lastResponse}}"
              >
    </iron-ajax>
    <pre>[[json(lastResponse)]]</pre>
  </template>
  <script>
    class XFoo extends Polymer.Element {
      static get is() { return 'x-foo'; }

      static get properties() {
        return {
          foo: {
            type: String,
            value: 'bar'
          }
        }
      }

      json(obj) {
        return JSON.stringify(obj, null, 2);
      }
    }
    customElements.define(XFoo.is, XFoo);
  </script>
</dom-module>

demo