jwt
jwt
https://jwt.io/
JSON Web Tokens are an open, industry standard RFC 7519 method for representing claims securely between two parties.
JWT.IO allows you to decode, verify and generate JWT.
introduction
https://jwt.io/introduction
When should you use JSON Web Tokens?
Here are some scenarios where JSON Web Tokens are useful:
Authorization: This is the most common scenario for using JWT. Once the user is logged in, each subsequent request will include the JWT, allowing the user to access routes, services, and resources that are permitted with that token. Single Sign On is a feature that widely uses JWT nowadays, because of its small overhead and its ability to be easily used across different domains.
Information Exchange: JSON Web Tokens are a good way of securely transmitting information between parties. Because JWTs can be signed—for example, using public/private key pairs—you can be sure the senders are who they say they are. Additionally, as the signature is calculated using the header and the payload, you can also verify that the content hasn't been tampered with.
Payload
The second part of the token is the payload, which contains the claims. Claims are statements about an entity (typically, the user) and additional data. There are three types of claims: registered, public, and private claims.
Registered claims: These are a set of predefined claims which are not mandatory but recommended, to provide a set of useful, interoperable claims. Some of them are: iss (issuer), exp (expiration time), sub (subject), aud (audience), and others.
Notice that the claim names are only three characters long as JWT is meant to be compact.
Public claims: These can be defined at will by those using JWTs. But to avoid collisions they should be defined in the IANA JSON Web Token Registry or be defined as a URI that contains a collision resistant namespace.
Private claims: These are the custom claims created to share information between parties that agree on using them and are neither registered or public claims.
https://www.iana.org/assignments/jwt/jwt.xhtml
library
https://jwt.io/libraries
pyjwt
https://pyjwt.readthedocs.io/en/latest/algorithms.html#asymmetric-public-key-algorithms
Specifying an Algorithm
You can specify which algorithm you would like to use to sign the JWT by using the algorithm parameter:
>>> encoded = jwt.encode({"some": "payload"}, "secret", algorithm="HS512") >>> print(encoded) eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJzb21lIjoicGF5bG9hZCJ9.WTzLzFO079PduJiFIyzrOah54YaM8qoxH9fLMQoQhKtw3_fMGjImIOokijDkXVbyfBqhMo2GCNu4w9v7UXvnpA
When decoding, you can also specify which algorithms you would like to permit when validating the JWT by using the algorithms parameter which takes a list of allowed algorithms:
>>> jwt.decode(encoded, "secret", algorithms=["HS512", "HS256"]) {'some': 'payload'}
https://pyjwt.readthedocs.io/en/latest/api.html#exceptions