description: The app instance conventionally denotes the Fiber application.

🚀 Application

New

This method creates a new App named instance.
You can pass optional settings when creating a new instance

fiber.New(settings ...Settings) *App

package main
import "github.com/gofiber/fiber/v2"
func main() {
    app := fiber.New()
    // ...
    app.Listen(":3000")
}

Settings

You can pass application settings when calling New.

func main() {
    // Pass Settings creating a new instance
    app := fiber.New(fiber.Settings{
        Prefork:       true,
        CaseSensitive: true,
        StrictRouting: true,
        ServerHeader:  "Fiber",
    })
    // ...
    log.Fatal(app.Listen(":3000"))
}

Or change the settings after initializing an app.

func main() {
    app := fiber.New()
    // Or change Settings after creating an instance
    app.Settings.Prefork = true
    app.Settings.CaseSensitive = true
    app.Settings.StrictRouting = true
    app.Settings.ServerHeader = "Fiber"
    // ...
    log.Fatal(app.Listen(":3000"))
}

Settings fields

Static

Use the Static method to serve static files such as images, CSS and JavaScript.

By default, Static will serveindex.html files in response to a request on a directory.

app.Static(prefix, root string, config ...Static) // => with prefix

Use the following code to serve files in a directory named ./public

app.Static("/", "./public")
// => http://localhost:3000/hello.html
// => http://localhost:3000/js/jquery.js
// => http://localhost:3000/css/style.css

To serve from multiple directories, you can use Static multiple times.

// Serve files from "./public" directory:
app.Static("/", "./public")
// Serve files from "./files" directory:
app.Static("/", "./files")

Use a reverse proxy cache like NGINX to improve performance of serving static assets.

You can use any virtual path prefix (where the path does not actually exist in the file system) for files that are served by the Static method, specify a prefix path for the static directory, as shown below:

app.Static("/static", "./public")
// => http://localhost:3000/static/hello.html
// => http://localhost:3000/static/js/jquery.js
// => http://localhost:3000/static/css/style.css

If you want to have a little bit more control regarding the settings for serving static files. You could use the fiber.Static struct to enable specific settings.

// Static represents settings for serving static files
type Static struct {
    // Transparently compresses responses if set to true
    // This works differently than the github.com/gofiber/compression middleware
    // The server tries minimizing CPU usage by caching compressed files.
    // It adds ".fiber.gz" suffix to the original file name.
    // Optional. Default value false
    Compress bool
    // Enables byte range requests if set to true.
    // Optional. Default value false
    ByteRange bool
    // Enable directory browsing.
    // Optional. Default value false.
    Browse bool
    // Index file for serving a directory.
    // Optional. Default value "index.html".
    Index string
}

app.Static("/", "./public", fiber.Static{
  Compress:   true,
  ByteRange:  true,
  Browse:     true,
  Index:      "john.html"
})

HTTP Methods

Routes an HTTP request, where METHOD is the HTTP method of the request.

// HTTP methods support :param, :optional? and *wildcards
// You are required to pass a path to each method
app.All(path string, handlers ...func(*Ctx)) *Fiber
app.Get
app.Put
app.Post
app.Head
app.Patch
app.Trace
app.Delete
app.Connect
app.Options
// Use() will only match the beggining of each path
// i.e. "/john" will match "/john/doe", "/johnnnn"
// Use() does not support :param & :optional? in path
app.Use(handlers ...func(*Ctx))
app.Use(prefix string, handlers ...func(*Ctx)) *Fiber

app.Use("/api", func(c *fiber.Ctx) {
  c.Set("X-Custom-Header", random.String(32))
  c.Next()
})
app.Get("/api/list", func(c *fiber.Ctx) {
  c.Send("I'm a GET request!")
})
app.Post("/api/register", func(c *fiber.Ctx) {
  c.Send("I'm a POST request!")
})

Group

You can group routes by creating a *Group struct.

Signature

app.Group(prefix string, handlers ...func(*Ctx)) *Group

Example

func main() {
  app := fiber.New()
  api := app.Group("/api", cors())  // /api
  v1 := api.Group("/v1", mysql())   // /api/v1
  v1.Get("/list", handler)          // /api/v1/list
  v1.Get("/user", handler)          // /api/v1/user
  v2 := api.Group("/v2", mongodb()) // /api/v2
  v2.Get("/list", handler)          // /api/v2/list
  v2.Get("/user", handler)          // /api/v2/user
  log.Fatal(app.Listen(":3000"))
}

Listen

Binds and listens for connections on the specified address.

app.Listen(address string, tls ...*tls.Config) error

app.Listen(":8080")
app.Listen("8080")
app.Listen(":8080")
app.Listen("127.0.0.1:8080")

To enable TLS/HTTPS you can append a TLS config.

cer, err := tls.LoadX509KeyPair("server.crt", "server.key")
if err != nil {
    log.Fatal(err)
}
config := &tls.Config{Certificates: []tls.Certificate{cer}}
app.Listen(":443", config)

Serve

You can pass your own net.Listener using the Serve method.

app.Serve(ln net.Listener, tls ...*tls.Config) error

Serve does not support the **[Prefork** ]($original-application.md#settings)feature.

if ln, err = net.Listen("tcp4", ":8080"); err != nil {
    log.Fatal(err)
}
app.Serve(ln)

Test

Testing your application is done with the Test method. Use this method for creating _test.go files or when you need to debug your routing logic. The default timeout is 200ms if you want to disable a timeout completely, pass -1 as a second argument.

app.Test(req *http.Request, msTimeout ...int) (*http.Response, error)

// Create route with GET method for test:
app.Get("/", func(c *Ctx) {
  fmt.Println(c.BaseURL())              // => http://google.com
  fmt.Println(c.Get("X-Custom-Header")) // => hi
  c.Send("hello, World!")
})
// http.Request
req, _ := http.NewRequest("GET", "http://google.com", nil)
req.Header.Set("X-Custom-Header", "hi")
// http.Response
resp, _ := app.Test(req)
// Do something with results:
if resp.StatusCode == 200 {
  body, _ := ioutil.ReadAll(resp.Body)
  fmt.Println(string(body)) // => Hello, World!
}