Fixing the JSON Parse Error in a Webhook Response

• Ensure the Response is Valid JSON:
  • Double-check that every response from your webhook module is written with proper JSON syntax. The response must start with { or [ and must not include any extra characters outside the JSON structure.
  • For example, a valid JSON response is:
    {"status": "success", "data": {"value": 123}}
• Set the Correct Content-Type Header:
  • Within your HTTP response or whichever module sends back the webhook response, ensure that the HTTP header Content-Type: application/json is explicitly set. This guides Make to treat the response as JSON.
• Use the JSON Encode Function:
  • If you’re constructing the JSON response using a scripting or code module in Make, use the JSON encode function provided by the module. This helps avoid formatting mistakes. For example, in a JavaScript code module you can do:
  
  const responseData = {status: "success", data: {value: 123}}; const jsonResponse = JSON.stringify(responseData); // Send jsonResponse as your webhook response
  
  • This approach guarantees that your JSON is valid before being sent.
• Validate the Response in a Testing Environment:
  • Before enabling the webhook trigger, test your response using tools like Postman or cURL, ensuring that the JSON is valid and free of unexpected characters or formatting issues.
• Update the Make Scenario Settings:
  • If the outbound webhook is returning a text value rather than a parsed JSON, use the “Parse JSON” module inside your scenario. This module takes the raw response and guarantees that downstream modules get a proper JSON object.
  • Simply add the module after the webhook response, map the raw response field, and the module will attempt to parse it. Review any field mapping that might be misinterpreting the response.
• Remove Any Extra Whitespace or Characters:
  • Sometimes stray spaces, line breaks, or UTF-8 BOM characters before JSON start can cause parsing issues. Ensure that your code or service sending the response trims all extra characters. In a code example, it might be structured like this:
    // Prepare the clean JSON response without extra whitespace const responseData = {status: "success", data: {value: 123}}; const jsonResponse = JSON.stringify(responseData).trim(); // Return or output jsonResponse as the final response
• Review Scenario Mapping:
  • Within your Make scenario, inspect the field mapping for the webhook response. Ensure that it expects a JSON structure. If needed, explicitly parse or convert text fields into structured data using Make’s built-in functions.
• Re-run and Verify:
  • After applying these changes, run your scenario manually. Monitor the response by using the “History” panel to confirm that Make is now properly parsing the JSON without errors.