JSON.parse(JSON.stringify(userData))
Unexpected token W in JSON at position 0
It's because a simple string (plain text) is returned as the response. The text is not a valid JSON. So when you try to do res.json(), it calls JSON.parse(data). Try and do it with the string you provided, and you will get the same error.
use res.text() instead of res.json()Unexpected token W in JSON at position 0
It's because a simple string (plain text) is returned as the response. The text is not a valid JSON. So when you try to do res.json(), it calls JSON.parse(data). Try and do it with the string you provided, and you will get the same error.
use res.text() instead of res.json()Unexpected token W in JSON at position 0
It's because a simple string (plain text) is returned as the response. The text is not a valid JSON. So when you try to do res.json(), it calls JSON.parse(data). Try and do it with the string you provided, and you will get the same error.
use res.text() instead of res.json()Check out JSON syntax. https://jsonlint.com/The wording of the error message corresponds to what you get from Google Chrome when you run JSON.parse('<...'). I know you said the server is setting Content-Type:application/json, but I am led to believe the response body is actually HTML.
Feed.js:94 undefined "parsererror" "SyntaxError: Unexpected token < in JSON at position 0"
with the line console.error(this.props.url, status, err.toString()) underlined.
The err was actually thrown within jQuery, and passed to you as a variable err. The reason that line is underlined is simply because that is where you are logging it.
I would suggest that you add to your logging. Looking at the actual xhr (XMLHttpRequest) properties to learn more about the response. Try adding console.warn(xhr.responseText) and you will most likely see the HTML that is being received.