Serving static files

func main() {
    app := iris.New()
    app.Favicon("./resources/favicon.ico")
    app.HandleDir("/assets", iris.Dir("./assets"))

    app.Listen(":8080")
}

The HandleDir method accepts a third, optional argument of DirOptions:

type DirOptions struct {
    // Defaults to "/index.html", if request path is ending with **/*/$IndexName
    // then it redirects to **/*(/) which another handler is handling it,
    // that another handler, called index handler, is auto-registered by the framework
    // if end developer does not managed to handle it by hand.
    IndexName string
    // PushTargets filenames (map's value) to
    // be served without additional client's requests (HTTP/2 Push)
    // when a specific request path (map's key WITHOUT prefix)
    // is requested and it's not a directory (it's an `IndexFile`).
    //
    // Example:
    //     "/": {
    //         "favicon.ico",
    //         "js/main.js",
    //         "css/main.css",
    //     }
    PushTargets map[string][]string
    // PushTargetsRegexp like `PushTargets` but accepts regexp which
    // is compared against all files under a directory (recursively).
    // The `IndexName` should be set.
    //
    // Example:
    // "/": regexp.MustCompile("((.*).js|(.*).css|(.*).ico)$")
    // See `iris.MatchCommonAssets` too.
    PushTargetsRegexp map[string]*regexp.Regexp

    // Cache to enable in-memory cache and pre-compress files.
    Cache DirCacheOptions
    // When files should served under compression.
    Compress bool

    // List the files inside the current requested directory if `IndexName` not found.
    ShowList bool
    // If `ShowList` is true then this function will be used instead
    // of the default one to show the list of files of a current requested directory(dir).
    // See `DirListRich` package-level function too.
    DirList DirListFunc

    // Files downloaded and saved locally.
    Attachments Attachments

    // Optional validator that loops through each requested resource.
    AssetValidator func(ctx *context.Context, name string) bool
}

Learn more about file-server.