JWT token creation using DataWeave

Photo by Shubham Dhage on Unsplash.

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In this post:

• Sample JWT token

• How to create JWT using Java

• How to create JWT using DataWeave

• Summary

• References

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Security implementations have been revolutionary through OAuth 2.0, OpenID Connect, SAML, etc. OAuth 2.0 and OpenID connect mostly use JWT as a token format. JWT is a very familiar term for the API fraternity.

There are instances where we need to create a JWT token to authorize our APIs to a service or authorize any client if we are using any custom solutions for authentication/authorization.

Let’s take a deeper look at JWT tokens.

Sample JWT token

ewogICJhbGciOiAiSFMyNTYiLAogICJ0eXAiOiAiSldUIiwKICAia2lkIjogIjEwMSIKfQ.ewogICJpc3MiOiAiR1RBIiwKICAiaWF0IjogMTY1NjQyMTQ0NiwKICAicmVxdWVzdGVkU2NvcGUiOiBbCiAgICAieG90cCIKICBdCn0.l2slJ86T7J3at9UG5esKMi5B9h02WjcpIuMZm_5mxzM

Let's see the basic structure of this token. (Visit https://jwt.io/#debugger-io)

As you can see in the image, the token is decoded into three parts,

1. Header

ewogICJhbGciOiAiSFMyNTYiLAogICJ0eXAiOiAiSldUIiwKICAia2lkIjogIjEwMSIKfQ

2. Payload

ewogICJpc3MiOiAiR1RBIiwKICAiaWF0IjogMTY1NjQyMTQ0NiwKICAicmVxdWVzdGVkU2NvcGUiOiBbCiAgICAieG90cCIKICBdCn0

3. Signature

l2slJ86T7J3at9UG5esKMi5B9h02WjcpIuMZm_5mxzM

We will see in the following topic how to create this token.

How to create JWT using Java

There are multiple libraries to do this in JAVA: I always try to use the simplest code.

The token generated:

eyJraWQiOiIxMDEiLCJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJHVEEiLCJyZXF1ZXN0ZWRTY29wZSI6WyJ4b3RwIl0sImlhdCI6MTY1NjQyMjk3Nn0.3kM0_DUuJCIig2OlyqxqnjODUxRvTA93d9Tgu-ZhOgw

Let’s decode this token.

How to create JWT using DataWeave

JAVA seems to be very technical. Let’s switch to our magical language.

The token generated:

ewogICJhbGciOiAiSFMyNTYiLAogICJ0eXAiOiAiSldUIiwKICAia2lkIjogIjEwMSIKfQ.ewogICJpc3MiOiAiR1RBIiwKICAiaWF0IjogMTY1NjQyMjk3NiwKICAicmVxdWVz