Can't catch error from server

Webix JS
1

Hello webix,
I use
webix.ajax().response(“blob”).post(api/lover).then(r=>{//code})
it’s ok when server execute successful, but if server
throw new Error().
The Error only show on server, in browser console log
500 (Internal Server Error)

I dont know how to catch it on the client side and show it by webix.message

Love,

2

try to use catch method

webix.ajax().response("blob")
    .post('api/lover')
    .then(r=>{/*code*/})
    .catch(err => {
        console.log(err);
    });
3

it’s only show on the console that:

app.js:63 Uncaught DOMException: Failed to read the ‘responseText’ property from ‘XMLHttpRequest’: The value is only accessible if the object’s ‘responseType’ is ‘’ or ‘text’ (was ‘blob’).

4

Hello @duynq2197 ,
Unfortunately, I can’t repeat the described issue. Could you please provide more details?
As an alternative to the catch() method, you could try using the onAjaxError event:

webix.attachEvent("onAjaxError", function(xhr){
  console.log(xhr);
  if(xhr.status===500){
    webix.message({type: 'error', text:"Please try again"});
  }
});
5

hi.
onAjaxError can catch this error. And “Uncaught DOMException: Failed to read the ‘responseText’ property from ‘XMLHttpRequest’” notice came from that thing.

The case is :
In client
webix.ajax().response(“blob”).post(api/lover).then(r=>{//code})
In server:
i use ‘docxtemplater’ lib to create word file and res.end(out, ‘binary’)

thanks

6

Because blob is returned in the response (responseType = blob). Additionally, you need to process this blob (so it still contains an error message).
To do this, you can use the built-in browser object of type FileReader (it can read data from Blob (and from File, too)) and its API:

webix.attachEvent("onAjaxError", function(xhr){
  const reader = new FileReader();
  let response;
  reader.onloadend = (e) => {
    response = JSON.parse(reader.result);
    console.log(response);
  }
  reader.readAsText(xhr.response);  //read the data as a text string with the given encoding (utf-8 by default)

  if(xhr.status===500){
    webix.message({type: 'error', text:"Please try again"});
  }
});
7

ok it’s really ok. I wish webix will improve to handle this . Thanks