A quick and dirty JWT/JWKS endpoint validator

main.go

package main

import (
	"log"
	"time"
    // remember go get these libs
	"github.com/dgrijalva/jwt-go"
	"github.com/MicahParks/keyfunc"
)

func main() {

	// Get the JWKS URL.
	jwksURL := "https://sblpf.test.com/ext/oauth/jwks"

	// 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 := "eyJhbGciOiJSUzI1NiIsImtpZCI6ImsxIiwicGkuYXRtIjoiNTdpdiJ9.eyJzY29wZSI6W10sImNsaWVudF9pZF9uYW1lIjoic3BvcmtfYmZmX3NhbmRib3giLCJpc3MiOiJwcm9kdWN0Y29yZSIsImZvbyI6ImJhciIsImV4cCI6MTYyNDQ2NzEyMn0.TFa1x1PGZGRbo9ZAH4iGCQIX1e5QRAj-h503Kvm4WHYfEt2HG7hfmIoLzTieKOocO-Oo9QDQPOxfhtDdcHo6Wruk9XOZeAYxH70_V4u4kkG5SWKy-Mz_G3o1HMp_YPFgeZV8nRx8UCQmZD-CSWg4_Bzo5Xrbc82K4m8lKHwxkvYDYkusudfz1Pwz-iT6rAmfJ5-6qJMuP5QyeDaA3ShAuFXKG9vEHcMgkLZXL_oUYNU6qZ9G1wVeO2c51ObP350dir-V1cuAngUR4jWJGPvJKjB9NQZ4xEEycvTOmwHj_mFgeY2w4HXVuzg62o2xPlP8a-Olxg-1S0YXjinoZJzW3w"

	// 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.")
}