middleware.go

package main

import (
	"github.com/paulbellamy/ratecounter"
	"net/http"
	"time"
)

var GlobalRate *ratecounter.RateCounter = ratecounter.NewRateCounter(1 * time.Second)

type TykMiddlewareImplementation interface {
	New()
	GetConfig() (interface{}, error)
	ProcessRequest(w http.ResponseWriter, r *http.Request, configuration interface{}) (error, int) // Handles request
	IsEnabledForSpec() bool
}

func CreateDynamicMiddleware(MiddlewareName string, IsPre, UseSession bool, tykMwSuper *TykMiddleware) func(http.Handler) http.Handler {
	dMiddleware := &DynamicMiddleware{
		TykMiddleware:       tykMwSuper,
		MiddlewareClassName: MiddlewareName,
		Pre:                 IsPre,
		UseSession:          UseSession,
	}

	return CreateMiddleware(dMiddleware, tykMwSuper)
}

func CreateDynamicAuthMiddleware(MiddlewareName string, tykMwSuper *TykMiddleware) func(http.Handler) http.Handler {
	dMiddleware := &DynamicMiddleware{
		TykMiddleware:       tykMwSuper,
		MiddlewareClassName: MiddlewareName,
		Auth:                true,
		UseSession:          false,
	}

	return CreateMiddleware(dMiddleware, tykMwSuper)
}

// Generic middleware caller to make extension easier
func CreateMiddleware(mw TykMiddlewareImplementation, tykMwSuper *TykMiddleware) func(http.Handler) http.Handler {
	// construct a new instance
	mw.New()

	// Pull the configuration
	thisMwConfiguration, confErr := mw.GetConfig()

	if confErr != nil {
		log.Fatal("[Middleware] Configuration load failed")
		//handler := ErrorHandler{tykMwSuper}
		//handler.HandleError(w, r, confErr.Error(), 403)
	}

	aliceHandler := func(h http.Handler) http.Handler {
		thisHandler := func(w http.ResponseWriter, r *http.Request) {

			if (tykMwSuper.Spec.CORS.OptionsPassthrough) && (r.Method == "OPTIONS") {
				h.ServeHTTP(w, r)
			} else {
				reqErr, errCode := mw.ProcessRequest(w, r, thisMwConfiguration)
				if reqErr != nil {
					handler := ErrorHandler{tykMwSuper}
					handler.HandleError(w, r, reqErr.Error(), errCode)
					return
				}

				// Special code, stops execution
				if errCode == 1666 {
					// Stop
					log.Info("[Middleware] Received stop code")
					return
				}

				// Special code, bypasses all other execution
				if errCode != 666 {
					// No error, carry on...
					h.ServeHTTP(w, r)
				}
			}

		}

		return http.HandlerFunc(thisHandler)
	}

	return aliceHandler
}