validation

jwt.KeyFunckidgithub.com/dgrijalva/jwt-gojwt.KeyFunchttps://keycloak.example.com/auth/realms/example/protocol/openid-connect/certs

package main

import (
    "encoding/json"
    "log"

    "github.com/dgrijalva/jwt-go"

    "github.com/MicahParks/keyfunc"
)

func main() {

    // Get the JWKS as JSON.
    var jwksJSON json.RawMessage = []byte(`{"keys":[{"kty":"RSA","e":"AQAB","use":"sig","kid":"MjhhMDk2N2M2NGEwMzgzYjk2OTI3YzdmMGVhOGYxNjI2OTc5Y2Y2MQ","alg":"RS256","n":"zZU9xSgK77PbtkjJgD2Vmmv6_QNe8B54eyOV0k5K2UwuSnhv9RyRA3aL7gDN-qkANemHw3H_4Tc5SKIMltVIYdWlOMW_2m3gDBOODjc1bE-WXEWX6nQkLAOkoFrGW3bgW8TFxfuwgZVTlb6cYkSyiwc5ueFV2xNqo96Qf7nm5E7KZ2QDTkSlNMdW-jIVHMKjuEsy_gtYMaEYrwk5N7VoiYwePaF3I0_g4G2tIrKTLb8DvHApsN1h-s7jMCQFBrY4vCf3RBlYULr4Nz7u8G2NL_L9vURSCU2V2A8rYRkoZoZwk3a3AyJiqeC4T_1rmb8XdrgeFHB5bzXZ7EI0TObhlw"}]}`)

    // Create the JWKS from the resource at the given URL.
    jwks, err := keyfunc.New(jwksJSON)
    if err != nil {
        log.Fatalf("Failed to create JWKS from resource at the given URL.\nError: %s", err.Error())
    }

    // Get a JWT to parse.
    jwtB64 := "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6ImI2TnozUDJwMHg1QWpfWENsUmhrVDFzNlNIQSJ9.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.K1iPtdXiuicuDPaLC6Exw/7UpJVW6Uy1tPpJlfZ29Vqs9M1zR00JpKxvymQMAzbD0GHlXPPsZmhDxOn0WMAPfr1Xi8tiruTLXNbwUPJ/SOovt+zK4JGtrydhc4iv2EROhMUk2uwJUb4DFjqKZRhBvtCW7fRtdtI9yJL4W4OK8Ld90yOb97usPjEPz8S4E4uNrb5lE2rLzIp+EaPwA232lDkhS8gGPIKdlLG1IdEfQ4cFU1VIplvWoHzprF9mGR0ahT2QGgmGE3AcBfkURk8VzIKDG/UcBA9eHu3XGg28j3OvIXWwJhd7Hi+jTqvggi0hplao8ElvjNBw/wNy2UO9WA=="

    // Parse the JWT.
    token, err := jwt.Parse(jwtB64, jwks.KeyFunc)
    if err != nil {
        log.Fatalf("Failed to parse the JWT.\nError: %s", err.Error())
    }

    // Check if the token is valid.
    if !token.Valid {
        log.Fatalf("The token is not valid.")
    }

    log.Println("The token is valid.")
}

package main

import (
    "log"
    "time"

    "github.com/dgrijalva/jwt-go"

    "github.com/MicahParks/keyfunc"
)

func main() {

    // Get the JWKS URL.
    jwksURL := "https://keycloak.example.com/auth/realms/example/protocol/openid-connect/certs"

    // Create the keyfunc options. Refresh the JWKS every hour and log errors.
    refreshInterval := time.Hour
    options := keyfunc.Options{
        RefreshInterval: &refreshInterval,
        RefreshErrorHandler: func(err error) {
            log.Printf("There was an error with the jwt.KeyFunc\nError: %s", err.Error())
        },
    }

    // Create the JWKS from the resource at the given URL.
    jwks, err := keyfunc.Get(jwksURL, options)
    if err != nil {
        log.Fatalf("Failed to create JWKS from resource at the given URL.\nError: %s", err.Error())
    }

    // Get a JWT to parse.
    jwtB64 := "eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6ImI2TnozUDJwMHg1QWpfWENsUmhrVDFzNlNIQSJ9.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.K1iPtdXiuicuDPaLC6Exw/7UpJVW6Uy1tPpJlfZ29Vqs9M1zR00JpKxvymQMAzbD0GHlXPPsZmhDxOn0WMAPfr1Xi8tiruTLXNbwUPJ/SOovt+zK4JGtrydhc4iv2EROhMUk2uwJUb4DFjqKZRhBvtCW7fRtdtI9yJL4W4OK8Ld90yOb97usPjEPz8S4E4uNrb5lE2rLzIp+EaPwA232lDkhS8gGPIKdlLG1IdEfQ4cFU1VIplvWoHzprF9mGR0ahT2QGgmGE3AcBfkURk8VzIKDG/UcBA9eHu3XGg28j3OvIXWwJhd7Hi+jTqvggi0hplao8ElvjNBw/wNy2UO9WA=="

    // Parse the JWT.
    token, err := jwt.Parse(jwtB64, jwks.KeyFunc)
    if err != nil {
        log.Fatalf("Failed to parse the JWT.\nError: %s", err.Error())
    }

    // Check if the token is valid.
    if !token.Valid {
        log.Fatalf("The token is not valid.")
    }

    log.Println("The token is valid.")
}