Execution Contexts

GET vs POST, ExecutionContextType, ExecutionContextName, and how to detect the execution environment.

SSJS exposes information about how the current page was invoked through the Platform.Request namespace. Understanding the execution context lets you write a single page that handles both GET and POST scenarios.

ExecutionContextType

Platform.Request.Method returns the HTTP verb: "GET" or "POST". Use it to distinguish form submissions from initial page loads:

<script runat="server">
Platform.Load("core", "1.1.5");

var method = Platform.Request.Method;

if (method === "POST") {
    // Handle form submission
    var email = Platform.Request.GetFormField("email");
    // ... process the form ...
    Write("<p>Thanks! We received: " + email + "</p>");
} else {
    // Render the form
    Write('<form method="post">');
    Write('<input name="email" type="email" placeholder="Your email">');
    Write('<button type="submit">Submit</button>');
    Write('</form>');
}
</script>

ExecutionContextName

Platform.Request.GetQueryStringParameter("_pageId") returns the CloudPages page ID. The system variable ExecutionContextName (when available) contains the name of the Automation or context that triggered execution.

In CloudPages, these built-in names are available:

Variable	Description
Platform.Request.Method	"GET" or "POST"
Platform.Request.GetQueryStringParameter(name)	Value from URL query string
Platform.Request.GetFormField(name)	Value from POST body (application/x-www-form-urlencoded)
Platform.Request.GetPostData()	Entire raw POST body (call only once)
Platform.Request.GetCookieValue(name)	Cookie value
Platform.Request.GetRequestHeader(name)	HTTP request header

Detecting the Environment

You can use feature detection to write code that degrades gracefully across contexts:

<script runat="server">
// Detect if we're in a web context (CloudPage vs email/automation)
var isWebContext = (Platform.Request.Method !== null &&
                   Platform.Request.Method !== "");

if (isWebContext) {
    var qs = Platform.Request.GetQueryStringParameter("debug");
    if (qs === "1") {
        // Show debug output
    }
}
</script>

GET Parameters

Read individual query string parameters with Platform.Request.GetQueryStringParameter():

<script runat="server">
var subscriberKey = Platform.Request.GetQueryStringParameter("sk");
var campaignId    = Platform.Request.GetQueryStringParameter("cid");

// Parameters not present in the URL return an empty string ""
if (!subscriberKey) {
    Platform.Response.Redirect("/error?code=no_sk", false);
}
</script>

Encrypted parameters: Use AMPscript’s CloudPagesURL() to generate URLs with encrypted parameters. Decrypt with AMPscript’s DecryptSymmetric() or rely on SFMC’s built-in decryption for CloudPagesURL-generated links.

POST Body

The POST body is available via two methods:

// Get a specific form field (application/x-www-form-urlencoded)
var email = Platform.Request.GetFormField("email");

// Get the entire raw POST body
var rawBody = Platform.Request.GetPostData();
// ⚠️ GetPostData() can only be called ONCE per request

JSON POST body pattern:

<script runat="server">
Platform.Load("core", "1.1.5");

if (Platform.Request.Method === "POST") {
    var rawBody = Platform.Request.GetPostData();
    // ParseJSON returns null if rawBody is null/undefined
    var payload = Platform.Function.ParseJSON(rawBody + "");

    if (payload && payload.email) {
        // Process...
    }
}
</script>

The + "" coercion prevents ParseJSON from throwing a 500 error on null/undefined input.

Cookies

// Read a cookie
var token = Platform.Request.GetCookieValue("session_token");

// Set a cookie
function dateAdd(timestamp,intervalToAdd,intervalType) {
    Platform.Variable.SetValue("@dateAdd_ts",timestamp);
    Platform.Variable.SetValue("@dateAdd_add",intervalToAdd);
    Platform.Variable.SetValue("@dateAdd_type",intervalType);
    return Platform.Function.TreatAsContent("%%=DateAdd(@dateAdd_ts, @dateAdd_add, @dateAdd_type)=%%");
}
function formatDate(dateString,dateFormat,timeFormat,isoLocale) {
    Platform.Variable.SetValue("@formatDate_string",dateString);
    Platform.Variable.SetValue("@formatDate_date",dateFormat);
    Platform.Variable.SetValue("@formatDate_time",timeFormat);
    Platform.Variable.SetValue("@formatDate_iso",isoLocale);
    return Platform.Function.TreatAsContent("%%=FormatDate(@formatDate_string, @formatDate_date, @formatDate_time, @formatDate_iso)=%%");
}

var expiry = dateAdd(Now(), 30, "D");
var expiryStr = formatDate(expiry, "M/D/YYYY","H:MM:SS");
Platform.Response.SetCookie("session_token", tokenValue, expiryStr, true);
// Parameters: name, value, expiration-string, https-only

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