fetch() unexpected end of input

Question

I am using fetch() to grab data from api server. My error looks like this:

Uncaught (in promise) SyntaxError: Unexpected end of input at 
  fetch.then.blob.
         


        

Answer 1

You met with the CORS origin policy problem. To tackle this you need rights to access the server side API. In particular, you need to add a line in the header of php or another server endpoint:

message);

...
// End php
?>

Also, make sure NOT to have in the header of your server endpoint:

header("Access-Control-Allow-Credentials" : true);

Model of working fetch code with POST request is:

const data = {
        optPost: 'myAPI',
        message: 'We make a research of fetch'
    };
const endpoint = 'http://example.com/php/phpGetPost.php';

fetch(endpoint, {
    method: 'POST',
    body: JSON.stringify(data)
})
.then((resp) => resp.json())
.then(function(response) {
    console.info('fetch()', response);
    return response;
});