Asynchronous Variables

Asynchronous Variables

Asynchronous Variables are a special type of client-side variable in JENTIS that gather information asynchronously, typically from third-party sources such as APIs or tracking pixels.

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Key Characteristics

• Execution is asynchronous and may take up to 2 seconds.

• The entire state execution is paused until all asynchronous variables either:

  • Return a value via callback, or

  • Hit the timeout limit.

• Client-Tags that rely on asynchronous variables are also paused until those variables are resolved.

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When to Use

Use asynchronous variables when you need to fetch data dynamically from external sources before continuing the tracking execution.

Potential Use Cases:

• Retrieve a third-party cookie value or identifier from a pixel.

• Wait for external data before sending it to the JENTIS Environment.

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How It Works

To define an asynchronous variable, your variable function must include a call to:

this.sendHTTPRequest(...)

When this function is detected, the variable is automatically treated as asynchronous.

To complete the variable evaluation, you must call:

args.callback(returnValue);

This returns the value and resumes state and tag execution.

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Function: sendHTTPRequest

Signature

this.sendHTTPRequest(config: {
  url: string;
  method: string;
  contentType?: string;
  withCredentials?: boolean;
  data?: string | object;
}, callback: (response: any) => void): void

Parameters

• url (string, required): The endpoint to which the HTTP request will be sent.

• method (string, required): The HTTP method (e.g., "GET", "POST").

• contentType (string, optional): MIME type of the request body (e.g., "application/json" or "text/plain").

• withCredentials (boolean, optional): Whether or not to send credentials like cookies.

• data (string | JSON, optional): Payload to be sent with the request (for POST, etc.).

Return Value

The callback function receives the parsed HTTP response as its parameter.

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Example: Asynchronous Variable Fetching a Third-Party ID

function(args) {
  this.sendHTTPRequest({
      url: "https://track.adform.net/Serving/Cookie/?adfaction=getjs;adfcookname=uid",
      method: "GET",
      contentType: "text/plain",
      withCredentials: true
    },
    function(res) {
      args.callback(res.adform_id); // Return the ID from Adform
    }
  );
}

In this example:

• The Adform pixel is queried for a user ID.

• Once the ID is retrieved, it’s returned via args.callback.

• The variable resolves, and JENTIS continues state and tag processing.

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Execution Flow

Website (with JENTIS) 
    ↓
Trigger fires state with async variable
    ↓
State execution pauses
    ↓
Asynchronous variable sends request via `sendHTTPRequest`
    ↓
Waits up to 2 seconds for response
    ↓
Callback received (or timeout)
    ↓
State and client-tags resume
    ↓
Data is sent to JENTIS Environment

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Notes

• Always ensure that args.callback(...) is called; otherwise, the variable will timeout.

• Avoid long-running operations to maintain performance.

• Only use asynchronous variables when absolutely necessary, as they delay the full data submission process.

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Asynchronous variables are powerful tools that let you enrich your tracking setup with dynamic, external data—while still ensuring proper execution flow and consent handling through the JENTIS system.