gin gonic with jwt from auth0 (and CORS enabled)

main.go

package main

import (
	"github.com/auth0/go-jwt-middleware"
	"github.com/dgrijalva/jwt-go"
	"gopkg.in/gin-gonic/gin.v1"
)

func main() {
	startServer()
}

var jwtMiddleware = jwtmiddleware.New(jwtmiddleware.Options{
	ValidationKeyGetter: func(token *jwt.Token) (interface{}, error) {
		return []byte("your auth0 client secret here"), nil
	},
	SigningMethod: jwt.SigningMethodHS256,
})

func checkJWT() gin.HandlerFunc {
	return func(c *gin.Context) {
		jwtMid := *jwtMiddleware
		if err := jwtMid.CheckJWT(c.Writer, c.Request); err != nil {
			c.AbortWithStatus(401)
		}
	}
}

func corsMiddleware() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Writer.Header().Set("Access-Control-Allow-Origin", "http://localhost:3000")
		c.Writer.Header().Set("Access-Control-Max-Age", "86400")
		c.Writer.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE, UPDATE")
		c.Writer.Header().Set("Access-Control-Allow-Headers", "Origin, Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization")
		c.Writer.Header().Set("Access-Control-Expose-Headers", "Content-Length")
		c.Writer.Header().Set("Access-Control-Allow-Credentials", "true")

		if c.Request.Method == "OPTIONS" {
			c.AbortWithStatus(200)
		} else {
			c.Next()
		}
	}
}

func startServer() {
	r := gin.Default()
	r.Use(corsMiddleware())

	r.GET("/ping", func(g *gin.Context) {
		g.JSON(200, gin.H{"text": "Hello from public"})
	})

	r.GET("/secured/ping", checkJWT(), func(g *gin.Context) {
		g.JSON(200, gin.H{"text": "Hello from private"})
	})

	r.Run(":3002")
}

Awesome, you helped me out alot. None of the popular CORS frameworks was working for me, but this did!