The Session Decoder is a client-side javascript that extracts the userId from the FTSession_s cookie, without making a remote API call to the Session API. This utility method is useful in scenarios where you are interested in obtaining the userId from a session cookie without knowing if the session is still valid.
https://sessionapi.memb.ft.com/static/js/session-decoder-bundle.min.js
Include the session decoder javascript in your page:
To extract the userId from the FTSession_s cookie:
var sessionDecoder = new SessionDecoder(‘publicKey’);
var userId = sessionDecoder.extractUuidFromSession();
Where:
publicKey - used to verify the session token signature derived from the FTSession_s cookie. Please email: FT Membership Platform Team to obtain the public key.
Extracted FT userId will be returned.
| Error Message | Reason |
| Missing public key | No public key supplied when instantiating SessionDecoder |
| Missing FTSession_s cookie | No FTSession_s cookie found, thus the user hasn’t logged in. |
| Invalid session - incorrect format | The format of the FTSession_s cookie value is invalid. |
| Signature Verification failed | Either incorrect public key provided or the session token from FTSession_s is invalid |