auth

A simple (but opinionated) Golang authentication library with a very simple interface (below). You can use this library to pull in core authentication functionality (minting tokens, validating tokens, & registering) to your application quickly and easily.

type Auth interface {
	Register(user User, password string) error
	GetToken(email string, password string, reqPermissions Permissions) (token string, err error)
	Validate(token string) (*Claims, error)
}

A gRPC microservice wrapping this interface is in progress and can be found at suyashkumar/auth-grpc.

You only need to provide a database connectionString and signingKey, and everything else is taken care of for you including:

table and database setup (including uniqueness constraints and useful indicies)
hashing passwords using bcrypt on register
comparing hashed passwords on login
validation of new user fields like "Email" (TBD)
encoding and extraction of key fields stored in the JSON Web Token (JWT)
ensuring that a token's requested permissions does not exceed the user's maximum permission level

A minimal example is below:

a, _ := auth.NewAuthenticator(db_string, signing_key)

u := auth.User{
	UUID:               uuid.NewV4(),
	Email:              "test@test.com",
	MaxPermissionLevel: auth.PERMISSIONS_USER,
}

// Register a new user
a.Register(u, "password")

// Login as user
token, err := a.GetToken(u.Email, "password", auth.PERMISSIONS_USER)
if err != nil {
	log.Fatal(err)
}
fmt.Printf("JWT Token: %s\n\n", token)

// Validate the user's token
claims, _ := a.Validate(token)
fmt.Printf("%+v", claims)