Debugging Airtable script: JSON parsing error help needed

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1

Hey folks, I’m stuck with a weird error in my Airtable script block. It’s a simple script that sends updates to my app through an API. When I run it, I get this error:

ERROR
SyntaxError: Unexpected token C in JSON at position 0

at Unexpected token C in JSON at position 0

I’m scratching my head trying to figure out what’s wrong. The script fetches a record, processes some data, and sends a POST request. Here’s a simplified version of what I’m working with:

let myData = await fetchRecord();
let apiUrl = chooseEnvironment();

let payload = {
  items: [
    { ID: '9876', name: 'Ms Johnson' }
  ]
};

let jsonPayload = JSON.stringify(payload);

let response = await sendRequest(apiUrl, jsonPayload);
console.log(response);

function sendRequest(url, data) {
  // API call setup and execution
}

Any ideas what might be causing this JSON error? I’ve double-checked my data structures, but I’m probably missing something obvious. Thanks for any help!

2

I’ve encountered similar issues before. The error suggests you’re trying to parse non-JSON data as JSON. This often happens when the API returns an error message or HTML instead of the expected JSON response. To troubleshoot:\n\n1. Log the raw response before parsing.\n2. Verify the API endpoint is correct and accessible.\n3. Check if your authentication is valid.\n4. Ensure the API is expecting the data format you’re sending.\n\nIf you’re using ‘await’ correctly, the issue might be in the sendRequest function. Make sure it’s properly handling the response and returning the raw data, not an already parsed object. Without seeing that function, it’s hard to pinpoint the exact cause.

3

hey there, sounds like a tricky one! have u tried logging the response before parsing it? sometimes APIs return error messages as plain text instead of JSON. might be worth checking if the response starts with ‘Cannot’ or something similar. also, double-check ur API endpoint - could be hitting the wrong URL. good luck!

4

I’ve dealt with this exact issue in my Airtable scripts before. The problem is likely in your sendRequest function. If it’s automatically parsing the response as JSON, you’ll get this error when the server returns non-JSON data (like an error message).

Here’s what worked for me:

In your sendRequest function, make sure you’re returning the raw response text first. Then, in your main code, wrap the JSON parsing in a try-catch block. Something like this:

async function sendRequest(url, data) {
  const response = await fetch(url, {
    method: 'POST',
    body: data,
    headers: { "Content-Type": "application/json" }
  });
  return await response.text(); // Return raw text
}

// In your main code
try {
  let responseText = await sendRequest(apiUrl, jsonPayload);
  let responseJson = JSON.parse(responseText);
  console.log(responseJson);
} catch (error) {
  console.error('Error parsing response:', responseText);
}

This way, you can see exactly what the server is sending back, even if it’s not valid JSON. It’s saved me countless hours of debugging!