SSJS HTTP POST IN SFMC

On Cloud Pages or in emails (using AMPscript) you may want to trigger a journey entry from a landing page, or script activity using Marketing Cloud REST API. Here is an example to request the authentification token that you will need to be authorized to perfom APIs calls.

Generating Client Id and Secret

In marketing Cloud :

Go to setup > Apps > Installed Packages
Click on new to create a new package. Name it and enter a description
Once created click on Add component
Le’ts create an API Integration, pick Server-to-Server for instance
Select the scope of your integration

In addition of the Client Id and Client Secret, you will find under the REST Base URI section, your custom URL that you’ll use to for posting data.

SSJS Request Token

DEFINITION

Ordinal	Type		Description
1	string	Required	Destination URL for the HTTP POST request
2	string	Required	Value to pass for the Content-Type header
3	string	Required	POST request content
4	string	Required	Array of header names included in the request

For the given call var result = HTTP.Post(url, contentType, payload, headerNames, headerValues);:

URL : Request Token URL
ContentType : is application/json type
Payload : will contain your client id and secret

EXAMPLE REQUEST TOKEN

<script runat="server">
    Platform.Load("Core", "1.1.1");
    try {
        var url = 'https://{YourCustomURI}.auth.marketingcloudapis.com/v1/requestToken';
        var contentType = 'application/json';
        var payload = '{"clientId": "{cliendIdHere}","clientSecret": "ClientSecretHere"}';
        var result = HTTP.Post(url, contentType, payload); // HTTP POST call with parameters
        var resultCode = (result.StatusCode); // Returns the execution code, check here for more info https://developer.salesforce.com/docs/atlas.en-us.mc-apis.meta/mc-apis/error-handling.htm
        var obj = Platform.Function.ParseJSON(result.Response + ''); // Parsing the JSON Response to get the token
        var val = obj.accessToken;
        var BearerT = 'Bearer ' + val;
        // Debug info below
        Write(resultCode + '<br>');
        Write(BearerT + '<br>');
        if (resultCode === 200) {
            // Another API call here or something else     
        } else {
            // block of code to be executed if the condition1 is false
        }
    } catch (ex) {
        Write("error message: " + ex);
    }
</script>

If you want to pass this token through another POST (withing the if 200 area for instance) you’ll be able to put it into your 2nd post header. Example:
var jbHeaderNames = ["Authorization"];
var jbHeaderValues = [BearerT];
var jbResult = HTTP.Post(jbUrl, jbContentType, jbPayload, jbHeaderNames, jbHeaderValues);

SSJS Journey Builder API Entry Event

JOURNEY API ENTRY SOURCE

You will need to create first an API entry event. To do so :

Go in Journey Builder and click on Entry Sources
Click on New Event
Give it a name and a description them copy the EVENT DEFINITION KEY (you will need it into the API call later on)
Select the journey entry sendable data extension
You can add a filter and then save.

EXAMPLE FIRE EVENT HTTP POST

In this example we will retrieve the token that we requested in the query above. Our API call will use the interaction/v1/events REST API.

if (resultCode === 200) {
  var jbUrl = 'https://{YourCustomUri}.rest.marketingcloudapis.com/interaction/v1/events';
  var jbContentType = 'application/json';
  // Below we'll detail the subscriber key, the API event and in data we will detail the DE info to populate.
  var jbPayloadPart = {
    "ContactKey": ssjsVarSubscriberkey,
    "EventDefinitionKey": "{YourJbEntrySourceApiEventHere}",
    "EstablishContactKey": true,
    "Data": {
      "YourDeSubscriberkeyField": ssjsVarSubscriberkey,
      "YourDeEmailAddressField": ssjsVarEmailAddress,
      "YourDeFirstNameField": ssjsVarFirstName
    }
  };
  var jbPayload = Stringify(jbPayloadPart); // Creating a API readable JSON payload
  var jbHeaderNames = ["Authorization"];
  var jbHeaderValues = [BearerT]; // Token we retrieved previously
  var jbResult = HTTP.Post(jbUrl, jbContentType, jbPayload, jbHeaderNames, jbHeaderValues);
  var jbResultCode = (jbResult.StatusCode);
  var jbStry = (jbResult.Response + '');
  Write(jbResultCode + '<br>');
} else {
  // block of code to be executed if the condition1 is false
}

You can retrieve the information to pass by retrieveing a URL parameter value, or form submission, or simply by using lookup functions for example. You can also do it with AMPscript as it uses the same functions.