GetJWT

This function creates a JSON Web Token (JWT) of a JSON formatted payload.

JWT, or JSON Web Token, is an open standard used to share security information between a client and a server. A JWT contains encoded JSON objects, including a set of claims (for example, JSON formatted key-value pairs). JWTs are signed using a cryptographic algorithm to ensure that the claims cannot be altered after the token is issued. Essentially, a JWT provides a method for validating that the data contained within it can be trusted.

A JWT consists of three parts:

A header (Base64 encoded)
A payload of claims (also Base64 encoded)
An encrypted HMAC signature

These three parts appear as a concatenated string, delimited by periods. The signature is built from all parts, so if the JWT is modified, then signature will change and it won’t match the original signature.

Arguments

GetJWT(1,2,3)

Ordinal	Type	Required	Description
1	String	True	Secret as string value
2	String	True	Hash algorithm used to encrypt the signature. Valid values are `HS256`, `HS384`, or `HS512`.
3	String	True	The payload string to encode (typically in JSON format)

NOTE: This function does not encrypt the payload.

NOTE: GetJWTByKeyName is the recommended function for creating JWTs, as GetJWT exposes the hard-coded secret in the server-side code (so it’s not a secret anymore), whereas GetJWTByKeyName retrieves the secret from Key Management, and access to this platform feature can be limited to individual users or roles.

Example

%%[
var @json, @secret, @jwt

set @json = '{
  "ContactKey": "00Q6F00001APnymUAD",
  "FirstName": "Samantha",
  "LastName": "Smith",
  "Email": "samantha@limedash.com"
}'
set @secret = 'x!A%C*F-JaNdRgUkXp2s5v8y/B?E(G+K'
set @jwt = GetJWT(@secret, 'HS256', @json)

]%%

JWT: %%=v(@jwt)=%%

Output

JWT: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.ew0KICAiQ29udGFjdEtleSI6ICIwMFE2RjAwMDAxQVBueW1VQUQiLA0KICAiRmlyc3ROYW1lIjogIlNhbWFudGhhIiwNCiAgIkxhc3ROYW1lIjogIlNtaXRoIiwNCiAgIkVtYWlsIjogInNhbWFudGhhQGxpbWVkYXNoLmNvbSINCn0.QJw_GNupl6kaVf_MjlIWaykIOA9Z4pu_wPx4dvZGXzk