JavaScript code examples in Zaps

Each of the four examples below expects a name in the "Input Data" field.

A synchronous example might be something as trivial as:

return {id: 1234, hello: 'world!', name: inputData.name};

You can also bind the result to output—the code above has exactly the same behavior as the code below:

output = {id: 1234, hello: 'world!', name: inputData.name};

A synchronous example with an early empty return might be something like:

if (inputData.name === 'Larry') {
    return []; // we don't work for Larry!
}
return {id: 1234, hello: 'world!', name: inputData.name};

An asynchronous example might be something like:

callback(null, {id: 1234, hello: 'world!', name: inputData.name});

As of June 2018, Node.js version 8 is available in Code steps. That release made async // await available for general use, greatly simplifying asynchronous javascript code. You can read more about awaithere.

A more complex asynchronous example (no "Input Data" needed) is:

const res = await fetch('http://example.com/');
const body = await res.text();
return {id: 1234, rawHTML: body};
// or
// output = {id: 1234, rawHTML: body}

For older Code steps, you can do the same with promises:

fetch('http://example.com/')
  .then(function(res) {
    return res.text();
  })
  .then(function(body) {
   var output = {id: 1234, rawHTML: body};
    callback(null, output);
  })
  .catch(callback);

This example expects a name in the "Input Data" field:

if (inputData.name) {
  console.log('got name!', inputData.name);
}
return {id: 1234, hello: 'world!', name: inputData.name};

This example expects a rawNumber in the "Input Data" field:

return {
  calculatedNumber: Number(inputData.rawNumber) / 2
};

This example expects a rawText in the "Input Data" field:

return {
  firstEmail: (inputData.rawText.match(/([\w._-]+@[\w._-]+\.[\w._-]+)/gi) || [])[0]
};

This example expects a rawText in the "Input Data" field:

var emails = inputData.rawText.match(/([\w._-]+@[\w._-]+\.[\w._-]+)/gi) || [];
return emails.map(function(email) {
  return {email: email};
});

Because this returns an array like [] instead of a single object like {} this will activate follow up actions multiple times, one for each email found! If no emails are found, nothing happens.

This example expects a zipCode in the "Input Data" field:

const res = await fetch('http://api.openweathermap.org/data/2.5/weather?zip=' + inputData.zipCode + ',us');
const json = await res.json();
return json;

For older Code steps, you can do the same with promises:

fetch('http://api.openweathermap.org/data/2.5/weather?zip=' + inputData.zipCode + ',us')
  .then(function(res) {
    return res.json();
  })
  .then(function(json) {
    callback(null, json);
  })
  .catch(callback);

It isn't uncommon to want to stash some data away for the next run, and our StoreClient can do exactly that. For example, this is a counter that keeps track of how many times it is run:

const store = StoreClient('your secret here');
const count = await store.get('some counter')
const newCount = (count || 0) + 1;
await store.set('some counter', count);
return {count: newCount}

For older Code steps, you can do the same with promises:

var store = StoreClient('your secret here');
var outCount;
store
 .get('some counter')
  .then(function(count) {
    count = (count || 0) + 1;
    outCount = count;
    return store.set('some counter', count);
  })
  .then(function() {
    callback(null, {'the count': outCount});
  })
  .catch(callback);

Learn more about StoreClient.