Unexpected token in JSON.parse

Question

I'm using node and request js to get a json object from a 3rd party api. When I try to parse the data i get an error:

SyntaxError: Unexpected token

I then tried to parse the data in my front-end application which resulted in the following error (see the whitespace after token):

SyntaxError: Unexpected token in JSON at position 294512

So i tried to run it through Postman and see what was wrong. The returned JSON seems valid, and I also ran i through a JSON validator without problems.

After investigating the result a bit more i found that one attribute (Document Type) always had a white space inside double qoutes:

{
"F24434": {
    "Posting Date": "29-10-12",
    "Open": "No",
    "On Hold": "",
    "Document Type": " ",
    "External Document No.": "",
    "Due Date": "29-10-12",
    "Description": "xxxx",
    "Order No.": "",
    "Currency Code": "DKK",
    "Remaining Amount": "0",
    "Original Amount": "0",
    "Amount": "0",
    "User ID": "xxx",
    "Systemdato": "29-10-12",
    "Entry No.": "607121",
    "Vessel No.": "",
    "Port No.": ""
  }
}

I'm not sure if that causes the problem or could it be something else?

Unfortunately I don't have direct access to the API, so I cannot alter the way the data i structured.

Solution It turned out that it was the whitespace inside the double quotes. The solution was to remove all whitespaces before parsing:

.replace(/\s/g, '');

Answer 1

I just had the same problem and in my case it turned out that the string had many null chars appended at the end. Solved it with myString.split(String.fromCharCode(0)).join("").

A whitespace inside double quotes seems to me like a perfectly valid string. I don't think that was the issue in your case.