goMiddlewareChain

This is an express.js-like-middleware-chain for julienschmidt's httprouter

You can write your own middleware, and chain this to a lot of other middlewares (logging, auth,...).

Getting started

Install goMiddlewareChain

go get github.com/TobiEiss/goMiddlewareChain

Your first API

Here a simple example with a simple Ping-Pong-Handler chained with a JSONResponseHandler (from templates).

package main

import (
	"fmt"
	"log"
	"net/http"

	"github.com/julienschmidt/httprouter"
	"github.com/TobiEiss/goMiddlewareChain"
	"github.com/TobiEiss/goMiddlewareChain/templates"
)

// Ping return a simply pong
func Ping(response *goMiddlewareChain.Response, request *http.Request, params httprouter.Params) {
	// simply pong
	response.Status.Code = http.StatusOK
	response.Data = "pong"
}

func main() {
	router := httprouter.New()
	router.GET("/api/v0/ping", goMiddlewareChain.RequestChainHandler(templates.JSONResponseHandler, Ping))

	log.Fatal(http.ListenAndServe(":8080", router))
}

After running this code, run curl localhost:8080/api/v0/ping in a terminal. You will get the following:

{
    "data":"pong",
    "msg":"OK",
    "status":200
}

Isn't it cool?

restricted-requestChainHandler

In some cases you need a restriction to apply requestChain. For example an auth-restriction. You can use the RestrictedRequestChainHandler. If the RestrictHandler failed, the code doesn't pass the chain.

Same example with Auth:

package main

import (
	"log"
	"net/http"

	"github.com/TobiEiss/goMiddlewareChain"
	"github.com/TobiEiss/goMiddlewareChain/templates"
	"github.com/julienschmidt/httprouter"
)

// Ping return a simply pong
func Ping(response *goMiddlewareChain.Response, request *http.Request, params httprouter.Params) {
	// simply pong
	response.Status.Code = http.StatusOK
	response.Data = "pong"
}

func Auth(response *goMiddlewareChain.Response, request *http.Request, params httprouter.Params) bool {
	user := request.Header.Get("X-User")
	return user == "HomerSimpson"
}

func main() {
	router := httprouter.New()
	router.GET("/api/v0/ping", goMiddlewareChain.RestrictedRequestChainHandler(Auth, templates.JSONResponseHandler, Ping))

	log.Fatal(http.ListenAndServe(":8080", router))
}

Now run curl --header "X-User: HomerSimpson" localhost:8080/api/v0/ping in your terminal. You will get:

{
    "data":"pong",
    "msg":"OK",
    "status":200
}

If you run curl --header "X-User: BartSimpson" localhost:8080/api/v0/ping, you get:

{
	"msg":"failed by passing restrictHandler",
	"status":401
}

handler from templates

• logHandler is an easy handler to log all accesses
• jsonResponseHandler try to transform your response to valid json

You need more handler? Just let us now this.