***

title: Detect a session id cookie with TypeScript in Flows
updated: 2025-09-20T00:00:00.000Z
slug: docs/postman-flows/typescript/typescript-check-for-session-cookie
max-toc-depth: 2
----------------

This TypeScript example checks an API response for a `sails.sid` cookie. If a `sails.sid` cookie is present in the response, it could indicate that a session ID has been leaked. By using TypeScript to check for the `sails.sid` cookie in an **If** or **Condition** block, you can route the response to different blocks, depending on the result.

## Example JSON

The example uses JSON data from a GET request to `postman-echo.com` like this:

```json
{
  "body": {
    "args": {},
    "headers": {
      "host": "postman-echo.com",
      "x-request-start": "t1757972551.591",
      "connection": "close",
      "x-forwarded-proto": "https",
      "x-forwarded-port": "443",
      "x-amzn-trace-id": "Root=1-68c88847-aaaaaaaaaaaaaaaaaaaaaaaa",
      "user-agent": "PostmanRuntime/7.46.0",
      "accept": "*/*",
      "cache-control": "no-cache",
      "postman-token": "00000000-1111-2222-3333-444444444444",
      "accept-encoding": "gzip, deflate, br",
      "cookie": "sails.sid=s%3AdummySessionId1234567890.abcdef1234567890"
    },
    "url": "https://postman-echo.com/get"
  },
  "http": {
    "status": 200,
    "headers": {
      "Date": "Mon, 15 Sep 2025 21:42:31 GMT",
      "Content-Type": "application/json; charset=utf-8",
      "Content-Length": "621",
      "Connection": "keep-alive",
      "Server": "nginx",
      "ETag": "W/"26d-FAKEETAG1234567890"",
      "Set-Cookie": "sails.sid=s%3AdummySetCookieId0987654321.qwerty9876543210; Path=/; HttpOnly"
    }
  },
  "tests": [],
  "binary": false
}
```

## Check a response for sails.sid

The following TypeScript checks an API response in a variable named `response` for a `sails.sid` cookie:

```javascript
(response.body.headers["cookie"]?.includes("sails.sid"))
```

If the `sails.sid` cookie is present in the response, the TypeScript returns `true`. Otherwise, it returns `false`. You can use this example script in an **If** or **Condition** block to route the response data based on the result.

## Example

To see this TypeScript in an example flow, check out [TypeScript example 2: Check for session cookie](https://www.postman.com/postman/flows-snippets/flow/68c9822cd556a900131b528e).