Fetch API yields "TypeError: failed to fetch"

Question

I am on Chrome, and I see this bizarre error:

TypeError: failed to fetch

(yes, that is the whole error message).

Here is the code that generated the error:

fetch(logoUrl, {
    method: 'put',
    headers: {
      'Content-Type': 'image/jpeg',
      //encode credentials as base64
      'Authorization': 'Basic ' + btoa('cdt-deployer:xyz'),
    },
    body: imgFile // the file

  }).catch(function(err){
       // the error appears here
  })

what am I supposed to do? I have no idea what's wrong. I am simply trying to send a binary image file to another server (I cannot see the server logs).

Answer 1

From the Fetch API documentation:

A fetch() promise rejects with a TypeError when a network error is encountered, although this usually means a permissions issue or similar.

One of these may be possible causes of "network error":

• DNS problems
• the server at logoUrl is unavailable / erroneous
• Erroneous HTTP Headers causing server to ignore the request
• Browser aborted -- most likely due to navigation to another page before the fetch completes