Using JavaScript in Zapier Code to format incoming data as required JSON

Other Questions Zapier
1

I’m trying to handle an API that returns its data in a format that Zapier doesn’t accept. The API gives multiple JSON objects that need to be included in an array.

API Output:

{"city":"Warren Township","country":"United States"}
{"city":"New York","country":"United States"}
{"city":"Stamford","country":"United States"}

Zapier’s Requirement:

[{"city":"Warren Township","country":"United States"},
{"city":"New York","country":"United States"},
{"city":"Stamford","country":"United States"}]

I attempted to fix this issue with a Code by Zapier step using the following JavaScript:

let url = 'https://api.iterable.com/api/export/data.json?dataTypeName=emailOpen&range=Today&onlyFields=email&onlyFields=createdAt&onlyFields=templateId&onlyFields=messageId&onlyFields=campaigniD&onlyFields=contentID'
let iterableData = 'undefined'

let response = await fetch(url, {
    method: "GET",
    headers: {
    'Api-Key': '----------redacted----------------',
    },
});

iterableData = await response.text()

iterableData = iterableData.replace(/\}/g, ",")
iterableData = "[" + iterableData.slice(0, -2) + "]"
let iterableJSON = JSON.parse(iterableData)

output = {iterableJSON}

This method effectively modifies the API response into a correctly formatted JSON array for Zapier. The main steps involve replacing the endings of objects and enclosing the whole response in brackets, followed by parsing it.

2

Your approach works, but string replacement can break on edge cases. Better to split the response by newlines and parse each JSON object separately:

let response = await fetch(url, {
    method: "GET",
    headers: {
        'Api-Key': 'your-key-here'
    }
});

let data = await response.text();
let lines = data.trim().split('\n');
let jsonArray = lines.map(line => JSON.parse(line));

output = {data: jsonArray};

This treats each line as a separate JSON object (JSONL format) instead of doing string manipulation. You won’t get parsing errors if your data has commas or brackets in string values.

3

you’re working with jsonl format - that’s standard for streaming apis. skip the regex and try this instead: let jsonObjs = response.text().split('\n').filter(l => l.trim()).map(JSON.parse); output = {results: jsonObjs}; much cleaner than string manipulation and it handles empty lines for ya.

4

I’ve hit this JSONL parsing issue before. Your string replacement method will break if any JSON values contain closing braces. Here’s what works better: javascript let response = await fetch(url, { method: "GET", headers: { 'Api-Key': 'your-api-key' } }); let rawData = await response.text(); let validObjects = []; rawData.split('\n').forEach(line => { if (line.trim()) { try { validObjects.push(JSON.parse(line)); } catch (e) { console.log('Skipped invalid JSON:', line); } } }); output = {data: validObjects}; This handles blank lines and malformed responses without killing your entire Zap. The try-catch saves you from losing everything over one bad line.