How to get response header in react native android?

Question

Hello i want to get response header after fetch POST request. I tried to debug to see what inside response with console.log(response). I can get response bodies from responseData but i have no idea how to get the header. I want to get both header and the body. Please help. thanks:)

Here's the example what i've done:

   fetch(URL_REGISTER, {
      method: 'POST',
      body: formData
    })
      .then((response) => response.json())
      .then((responseData) => {
        if(responseData.success == 1){
          this.setState({
            message1: responseData.msg,
          });
        }
        else{
          this.setState({
            message1: responseData.msg,
          });
        }
      })
      .done();
    }, 

Solution 1

you can do like this

  fetchData() {
  var URL_REGISTER = 'https://www.example.com';
  fetch(URL_REGISTER, {method: 'POST',body: formData})
      .then(
          function(response) {
              console.log(response.headers.get('Content-Type'));
              console.log(response.headers.get('Date'));

              console.log(response.status);
              console.log(response.statusText);
              console.log(response.type);
              console.log(response.url);
              if (response.status !== 200) {
                  console.log('Status Code: ' + response.status);
                  return;
              }

              // Examine the text in the response
              response.json().then(function(data) {
                  console.log(data);
              });
          }
      )
      .catch(function(err) {
          console.log('Fetch Error', err);
      });
}

Read More about fetch: Introduction to fetch()

Solution 2

You can take the headers from response.headers

fetch(URL_REGISTER, {
  method: 'POST',
  body: formData
})
  .then((response) => {
    console.log(response.headers); //Returns Headers{} object
}

Solution 3

You should return response.json() like
return response.json();

Comments

[Admin]

i tried to edit like this .then((response) => {console.log(response.headers); response.json()}) , but when i run it, it show me the error because it not read response.json() . Any ideas?

[Admin]

Thanks, that's help me a lot :)

[Dévan Coetzee]

@sptra, .json() returns a promise, so to get the response as JSON you need to handle the promise: .then(function (response) { console.log(response.headers); return response.json(); }).then(function (json) { console.log(json); }).catch...

[Dévan Coetzee]

It is also important to note that due to W3 Standards only Cache-Control, Content-Language, Content-Type, Expires, Last-Modified and Pragma are accessible when making requests outside the domain.