Middlewares

• Cyclops supports middlewares and few middlewares come pre-included with the project and they are:

  • CORS
  • Panic Handler
  • Request Logger
  • Set Secure Headers with every request
  • Set Default Headers with every request

• Out of the above middlewares, PanicHandler and RequestLogger are enabled by default

• You can also add your own custom middlewares, the only thing to take care of when writing custom middlewares is that the function should take in http.Handler as a parameter and return http.Handler

Using CORS Middleware

Cyclops supports CORS and can be used as explained below

package main

import (
	"fmt"
	"github.com/flannel-dev-lab/cyclops/v2"
	"github.com/flannel-dev-lab/cyclops/v2/middleware"
	"github.com/flannel-dev-lab/cyclops/v2/router"
	"html/template"
	"net/http"
	"time"
)

func main() {

    cors := middleware.CORS{
    		AllowedOrigin: "https://www.admin.yombu.com",
    		AllowedHeaders: []string{"Content-Type", "referrer", "referrer-type"},
    		AllowedMethods: []string{"GET", "POST"},
    		AllowedCredentials: true,
    		ExposedHeaders: []string{"GET"},
    		MaxAge: 100,
    	}

	routerObj := router.New()
	routerObj.Get("/", middleware.NewChain(cors.CORSHandler).Then(Login))

	cyclops.StartServer(":8080", routerObj)
}

func Login(w http.ResponseWriter, r *http.Request) {
	response.SuccessResponse(200, w, nil)
}

Setting Default Headers with every request

package main

import (
	"fmt"
	"github.com/flannel-dev-lab/cyclops/v2/"
	"github.com/flannel-dev-lab/cyclops/v2/middleware"
	"github.com/flannel-dev-lab/cyclops/v2/response"
	"github.com/flannel-dev-lab/cyclops/v2/router"
	"net/http"
)

func main() {

	~~defaultHeaders := middleware.DefaultHeaders{
        ContentType: "application/json",
	}~~

    routerObj := router.New()
    routerObj.Get("/", middleware.NewChain(DefaultHeaders.DefaultHeaders).Then(Login))
    
    cyclops.StartServer(":8080", routerObj)
}

func Login(w http.ResponseWriter, r *http.Request) {
	response.SuccessResponse(200, w, nil)
}

When we run the above code, the response header Content-Type: application/json is set with every request

Middleware Chaining

If you want to use multiple middlewares for a request, cyclops allows you to do that as well. All you need to do is like below:

middleware.NewChain(defaultHeaders.DefaultHeaders, cors.CORSHandler).Then(http.HandlerFunc(Login))