Introduction

This page explains how to add a custom script for payload transformations. You will create a new script, add your code using IntelliSense, and then save changes ready for testing. Adding a new custom script can be broken down into three distinct stages:

1. Create a new script

2. Add script code

3. Test script code

This page walks through creating and testing a new script. We'll be adding a Javascript (node 18) script to change email addresses in a given payload to [email protected]. If you'd like to try this yourself, our script and test payload are available below.

module.exports = async function (data) {
    const payload = JSON. parse (data.payload);

   if (payload.customers) {
     payload.customers.forEach(customer => {
         customer.email = '[email protected]';
      })
    }

    return { "payload": JSON.stringify(payload) };
};

[
    {
        "id": 1000000001,
        "first_name": "Britney",
        "last_name": "Spears",
        "email": "[email protected]"
    },
    {
        "id": 1000000002,
        "first_name": "Madonna",
        "last_name": "Ciccone",
        "email": "[email protected]"
    },
    {
        "id": 1000000003,
        "first_name": "Elvis",
        "last_name": "Presley",
        "email": "[email protected]"
    }
]

Need to know

• The maximum memory size for a custom script is 512MB

• The maximum size of a custom script is 4GB

Creating a new script

Follow the steps below:

Step 1 Log into the Patchworks dashboard and select scripts from the left-hand navigation bar.

Step 2 Select the create script button from the scripts page:

Step 3 Add a unique name and a description for your script, then choose your preferred coding language:

Step 4 Click the create button. The new script is saved and you're now in edit mode, ready to add and test your code:

Adding your code

Follow the steps below:

Step 1 Move down to the code panel.

Step 2 Add your script code (remember that you can use IntelliSense for easy code entry) - for example:

Step 3 When you're ready to test the script, click the save and deploy button:

This saves the code and deploys it to Patchworks, ready for testing/use.

Testing your script

Follow the steps below:

Step 1 Move across to the test panel.

Step 2 Add/paste a payload that can be used to test your script - for example:

Step 3 If your script references variables or flow variables, you can also add variables for testing:

Step 4 Click the run button:

...the script runs against your test payload and results are displayed at the end - for example:

Step 5 Keep testing the script until you're satisfied that it's working as required.

Once these tests are complete, you can:

• Apply a payload-level script to process flows via the script shape

• Apply a field-level custom script to field transformations via the map shape

Introduction

When testing and debugging scripts, it can be useful to write specific information to logs after the script has finished processing.

You can do this by adding a logs array key to a script, with required output added as strings - for example:

function handle($data)
{
    $data['logs'] = ["Log message 1", "Log message 2"];
    return $data;
}

...is output as:

Need to know

• Log messages must be strings.

• A maximum of 500 characters (in total) is allowed.

• Use with care (especially in loops) as logs are output every time the script runs.