Middleware

Goroute supports common middleware pattern. In this guide we will use standart goroute middlewares and create new one.

Using middleware

package main

import (
	"github.com/goroute/route"
	"github.com/goroute/recover"
	"github.com/goroute/compress"
	"github.com/goroute/cors"
	"github.com/goroute/static"
	"log"
	"net/http"
)

func main() {
	mux := route.NewServeMux()

	mux.Use(
		recover.New(),
		compress.New(),
		cors.New(),
		static.New(
			static.HTML5(true),
			static.Root("./dist"),
		),
	)

	mux.GET("/", func(c route.Context) error {
		return c.String(http.StatusOK, "Hello!")
	})

	log.Fatal(http.ListenAndServe(":9000", mux))
}

Creating new middleware

To add our own middleware we just need to create a new func which returns route.MiddlewareFunc.

Let’s create a new middleware which logs each request’s path.

import "github.com/goroute/route"

func logger() route.MiddlewareFunc {
	return func(c route.Context, next route.HandlerFunc) error {
		fmt.Println("Request Path:", c.Request().URL.Path)
		return next(c)
	}
}

mux.Use(logger())

Adding options

Common scenario for middleware is to have some configurable options. Let’s use go option pattern to allow passing options.

Let’s move our middleware to a new package called logger.

package logger

import "github.com/goroute/route"

type Options struct {
	Skipper route.Skipper
	Level string
}

type Option func(*Options)

func GetDefaultOptions() Options {
	return Options{
		Skipper: route.DefaultSkipper,
		Level:   "info",
	}
}

func Skipper(skipper route.Skipper) Option {
	return func(o *Options) {
		o.Skipper = skipper
	}
}

func Level(level string) Option {
	return func(o *Options) {
		o.Level = level
	}
}

func New(options ...Option) route.MiddlewareFunc {
	// Apply options.
	opts := GetDefaultOptions()
	for _, opt := range options {
		opt(&opts)
	}

	return func(c route.Context, next route.HandlerFunc) error {
		if opts.Skipper(c) {
			return next(c)
		}
		if opts.Level == "debug" {
			fmt.Println("Request Path:", c.Request().URL.Path)
		}
		return next(c)
	}
}

Now we can import our middleware and register with options.

import "mymodule/logger"

// ...

mux.Use(logger.New(logger.Level("debug")))

Guide

Using middleware

Creating new middleware

Adding options