yosssi/galaxy

Simple web framework for Go

Galaxy - Simple web framework for Go

Galaxy is a simple web framework for Go. This is inspired by Maritini but this does not rely on Dependency Injection at all. Go web applications can be built in a succinct manner by using Galaxy.

Getting Started

Here is a very small example code of a web application using Galaxy.

package main

import (
	"fmt"

	"github.com/yosssi/galaxy/core"
)

func main() {
	app := core.NewApplication()
	app.Get("/", func(ctx *core.Context) error {
		fmt.Fprintf(ctx.Res, "Hello world!")
		return ctx.Next()
	})
	app.Run(":3000")
}

Features

• Simple to use
• Inspired by Martini but does not reply on Dependency Injection
• Modular design - Every package has a single function. You can construct your own framework by choosing and importing packages as you like.
• Handler based framework - You can define the flow of the framework processes by stacking handlers.

Basics

Handler

A handler is a function whose type is core.Handler. This is the smallest unit of the processing flow.

Context

A context is a request context whose type is core.Context. It is generated in every request. It is passed to every handlers. A request (and application) context data is passed to every handlers via this struct.

Routing

app.Get("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Patch("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Post("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Put("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Delete("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Head("/", func(ctx *core.Context) error {
	return ctx.Next()
})

app.Options("/", func(ctx *core.Context) error {
	return ctx.Next()
})

Route handlers can be stacked.

app.Get(
	"/",
	func(ctx *core.Context) error {
		fmt.Println("handler #1")
		return ctx.Next()
	},
	func(ctx *core.Context) error {
		fmt.Println("handler #2")
		return ctx.Next()
	},
)

Pre & post handlers

You can define pre & post handlers which are invoked before / after route handlers. These handlers are invoke in any request.

app.UsePre(func(ctx *core.Context) error {
	fmt.Println("pre handler")
	return ctx.Next()
})

app.Get("/", func(ctx *core.Context) error {
	fmt.Println("route handler")
	return ctx.Next()
})

app.UsePost(func(ctx *core.Context) error {
	fmt.Println("post handler")
	return ctx.Next()
})

Provide the application / requext context data to every handler

You can provide the application / requext context data to every handler.

app := core.NewApplication()

// Set the data to the application context.
if err := app.SetData("text1", "this is an application context data"); err != nil {
	panic(err)
}

app.UsePre(func(ctx *core.Context) error {
	// Get the data from the application context.
	v, ok := app.GetData("text1")

	if ok {
		fmt.Println(v.(string))
	}

	// Set the data to the request context.
	if err := ctx.SetData("text1", "this is a request context data"); err != nil {
		return err
	}

	return ctx.Next()
})

app.UsePre(func(ctx *core.Context) error {
	// Get the data from the request context.
	v, ok := ctx.GetData("text1")

	if ok {
		fmt.Println(v.(string))
	}

	return ctx.Next()
})

Packages

• core - core functions of Galaxy web framework
• logger - handler for logging

package main

import (
	"fmt"

	"github.com/yosssi/galaxy/core"
	"github.com/yosssi/galaxy/logger"
)

func main() {
	app := core.NewApplication()
	app.UsePre(logger.Logger())
	app.Get("/", func(ctx *core.Context) error {
		fmt.Fprintf(ctx.Res, "Hello world")
		return ctx.Next()
	})
	app.Run(":3000")
}

• static - handler for serving static files

package main

import (
	"github.com/yosssi/galaxy/core"
	"github.com/yosssi/galaxy/static"
)

func main() {
	app := core.NewApplication()
	app.UsePre(static.Static("public"))
	app.Run(":3000")
}