fiber/middleware/filesystem

Filesystem Middleware

Filesystem middleware for Fiber that enables you to serve files from a directory.

⚠️ :params & :optionals? within the prefix path are not supported!
⚠️ To handle paths with spaces (or other url encoded values) make sure to set fiber.Config{ UnescapePath: true}

Table of Contents

• Filesystem Middleware
  • Table of Contents
  • Signatures
  • Examples
    • Config
    • embed
  • Config
    • Default Config

Signatures

func New(config Config) fiber.Handler

Examples

First import the middleware from Fiber,

import (
  "github.com/gofiber/fiber/v3"
  "github.com/gofiber/fiber/v3/middleware/filesystem"
)

Then create a Fiber app with app := fiber.New().

Config

// Provide a minimal config
app.Use(filesystem.New(filesystem.Config{
	Root: os.DirFS("./assets"),
}))

// Or extend your config for customization
app.Use(filesystem.New(filesystem.Config{
	Root:         os.DirFS("./assets"),
	Browse:       true,
	Index:        "index.html",
	NotFoundFile: "404.html",
	MaxAge:       3600,
}))

If your environment (Go 1.16+) supports it, we recommend using Go Embed instead of the other solutions listed as this one is native to Go and the easiest to use.

embed

Embed is the native method to embed files in a Golang excecutable. Introduced in Go 1.16.

package main

import (
	"embed"
	"io/fs"
	"log"
	"net/http"

	"github.com/gofiber/fiber/v3"
	"github.com/gofiber/fiber/v3/middleware/filesystem"
)

// Embed a single file
//go:embed index.html
var f embed.FS

// Embed a directory
//go:embed static/*
var embedDirStatic embed.FS

func main() {
	app := fiber.New()

	app.Use("/", filesystem.New(filesystem.Config{
		Root: f,
	}))

	// Access file "image.png" under `static/` directory via URL: `http://<server>/static/image.png`.
	// Without `PathPrefix`, you have to access it via URL:
	// `http://<server>/static/static/image.png`.
	app.Use("/static", filesystem.New(filesystem.Config{
		Root: embedDirStatic,
		Browse: true,
	}))

	log.Fatal(app.Listen(":3000"))
}

Config

// Config defines the config for middleware.
type Config struct {
	// Next defines a function to skip this middleware when returned true.
	//
	// Optional. Default: nil
	Next func(c fiber.Ctx) bool

	// Root is a FileSystem that provides access
	// to a collection of files and directories.
	//
	// Required. Default: nil
	Root fs.FS `json:"-"`

	// PathPrefix defines a prefix to be added to a filepath when
	// reading a file from the FileSystem.
	//
	// Optional. Default "."
	PathPrefix string `json:"path_prefix"`

	// Enable directory browsing.
	//
	// Optional. Default: false
	Browse bool `json:"browse"`

	// Index file for serving a directory.
	//
	// Optional. Default: "index.html"
	Index string `json:"index"`

	// The value for the Cache-Control HTTP-header
	// that is set on the file response. MaxAge is defined in seconds.
	//
	// Optional. Default value 0.
	MaxAge    int `json:"max_age"`

	// File to return if path is not found. Useful for SPA's.
	//
	// Optional. Default: ""
	NotFoundFile string `json:"not_found_file"`
}

Default Config

var ConfigDefault = Config{
	Next:       nil,
	Root:       nil,
	PathPrefix: ".",
	Browse:     false,
	Index:      "/index.html",
	MaxAge:     0,
}