JSON-Web-Tokens-JWT #

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JSON Web Token (JWT) Is a JSON object and it is considered one of the safest ways to transfer information between two participants. To create it, you need to define a header with general information on the token, payload data, such as the user id, his role, etc. First, the user logs on to the authentication server using an authentication key (it can be a username / password pair , or a Facebook key, or a Google key, or a key from another account). The JWT header contains information on how the JWT signature should be calculated . A header is also a JSON object that looks like this: header = { “alg”: “HS256”, “typ”: “JWT”}

It will be used when creating the signature. In the example the authentication server creates a JWT with information about the userId

payload = { “userId”: “b08f86af-35da-48f2–8fab-cef3904660bd” }

There is a list of standard applications for JWT payload — here are some of them:

• iss (issuer) — defines the application from which the token is sent.

// header eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9// payload eyJ1c2VySWQiOiJiMDhmODZhZi0zNWRhLTQ4ZjItOGZhYi1jZWYzOTA0NjYwYmQifQ// signature -xN_h82PHVTCMA9vdoHrcZxH-x5mb11y1537t3rGzcM

Now that we have all three components, we can create our JWT const token = encodeBase64Url(header) + ‘.’ + encodeBase64Url(payload) + ‘.’ + encodeBase64Url(signature) // JWT Token //eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJ1c2VySWQiOiJiMDhmODZhZi0zNWRhLTQ4ZjItOGZhYi1jZWYzOTA0NjYwYmQifQ.-xN_h82PHVTCMA9vdoHrcZxH-x5mb11y1537t3rGzcM **You can try to create your own JWT Online jwt.io .