New DirOptions.Cache field for in-memory caching and pre-compression for the fastest possible static file server

Read HISTORY.md it contains a breaking change, second parameter of HandleDir should be iris.Dir(...) instead of just a string

relative to: kataras#1556 (comment)


Former-commit-id: 14b48a06fb3b99287dff543932be2937a64233b9

Author: kataras

HISTORY.md

@@ -373,17 +373,38 @@ Other Improvements:
 
 - Fix [#1553](https://github.com/kataras/iris/issues/1553).
 
+- New `DirOptions.Cache` to cache assets in-memory among with their compressed contents (in order to be ready to served if client ask). Learn more about this feature by reading [all #1556 comments](https://github.com/kataras/iris/issues/1556#issuecomment-661057446). Usage:
+
+```go
+var dirOpts = DirOptions{
+    // [...other options]
+    Cache: DirCacheOptions{
+        Enable: true,
+        // Don't compress files smaller than 300 bytes.
+        CompressMinSize: 300,
+        // Ignore compress already compressed file types
+        // (some images and pdf).
+        CompressIgnore: iris.MatchImagesAssets,
+        // Gzip, deflate, br(brotli), snappy.
+        Encodings: []string{"gzip", "deflate", "br", "snappy"},
+        // Log to the stdout the total reduced file size.
+        Verbose: 1,
+    },
+}
+```
+
 - New `DirOptions.PushTargets` and `PushTargetsRegexp` to push index' assets to the client without additional requests. Inspirated by issue [#1562](https://github.com/kataras/iris/issues/1562). Example matching all `.js, .css and .ico` files (recursively):
 
 ```go
-var opts = iris.DirOptions{
-	IndexName: "/index.html",
-	PushTargetsRegexp: map[string]*regexp.Regexp{
+var dirOpts = iris.DirOptions{
+    // [...other options]
+    IndexName: "/index.html",
+    PushTargetsRegexp: map[string]*regexp.Regexp{
         "/": regexp.MustCompile("((.*).js|(.*).css|(.*).ico)$"),
         // OR:
-		// "/": iris.MatchCommonAssets,
-	},
-	Compress: true,
+        // "/": iris.MatchCommonAssets,
+    },
+    Compress: true,
 }
 ```
 
@@ -492,7 +513,7 @@ Breaking Changes:
 - `iris.Gzip` and `iris.GzipReader` replaced with `iris.Compression` (middleware).
 - `ctx.ClientSupportsGzip() bool` replaced with `ctx.ClientSupportsEncoding("gzip", "br" ...) bool`.
 - `ctx.GzipResponseWriter()` is **removed**.
-- `Party.HandleDir` now returns a list of `[]*Route` (GET and HEAD) instead of GET only.
+- `Party.HandleDir/iris.FileServer` now accepts a `http.FileSystem` instead of a string and returns a list of `[]*Route` (GET and HEAD) instead of GET only. Write: `app.HandleDir("/", iris.Dir("./assets"))` instead of `app.HandleDir("/", "./assets")` and `DirOptions.Asset, AssetNames, AssetInfo` removed, use `go-bindata -fs [..]` and `app.HandleDir("/", AssetFile())` instead.
 - `Context.OnClose` and `Context.OnCloseConnection` now both accept an `iris.Handler` instead of a simple `func()` as their callback.
 - `Context.StreamWriter(writer func(w io.Writer) bool)` changed to `StreamWriter(writer func(w io.Writer) error) error` and it's now the `Context.Request().Context().Done()` channel that is used to receive any close connection/manual cancel signals, instead of the deprecated `ResponseWriter().CloseNotify()` one. Same for the `Context.OnClose` and `Context.OnCloseConnection` methods.
 - Fixed handler's error response not be respected when response recorder was used instead of the common writer. Fixes [#1531](https://github.com/kataras/iris/issues/1531). It contains a **BREAKING CHANGE** of: the new `Configuration.ResetOnFireErrorCode` field should be set **to true** in order to behave as it used before this update (to reset the contents on recorder).

_examples/auth/cors/main.go

@@ -41,7 +41,7 @@ func main() {
 	app.WrapRouter(c.ServeHTTP)
 
 	// Serve ./public/index.html, main.js.
-	app.HandleDir("/", "./public")
+	app.HandleDir("/", iris.Dir("./public"))
 
 	// Register routes here...
 	app.Get("/data", listData)

_examples/bootstrapper/bootstrap/bootstrapper.go

@@ -108,7 +108,7 @@ func (b *Bootstrapper) Bootstrap() *Bootstrapper {
 
 	// static files
 	b.Favicon(StaticAssets + Favicon)
-	b.HandleDir(StaticAssets[1:len(StaticAssets)-1], StaticAssets)
+	b.HandleDir("/public", iris.Dir(StaticAssets))
 
 	// middleware, after static files
 	b.Use(recover.New())

_examples/desktop/webview/main.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"github.com/kataras/iris/v12"
-	"github.com/zserge/webview"
+	"github.com/webview/webview"
 )
 
 const addr = "127.0.0.1:8080"
@@ -18,7 +18,7 @@ const addr = "127.0.0.1:8080"
 	#
 	#
 	# Note: if you see "use option -std=c99 or -std=gnu99 to compile your code"
-	# please refer to: https://github.com/zserge/webview/issues/188
+	# please refer to: https://github.com/webview/webview/issues/188
 */
 func main() {
 	go runServer()

_examples/dropzonejs/README.md

@@ -101,7 +101,7 @@ func main() {
     app.RegisterView(iris.HTML("./views", ".html"))
 
     // Make the /public route path to statically serve the ./public/... contents
-    app.HandleDir("/public", "./public")
+    app.HandleDir("/public", iris.Dir("./public"))
 
     // Render the actual form
     // GET: http://localhost:8080

_examples/dropzonejs/README_PART2.md

@@ -168,7 +168,7 @@ func main() {
     app := iris.New()
     app.RegisterView(iris.HTML("./views", ".html"))
 
-    app.HandleDir("/public", "./public")
+    app.HandleDir("/public", iris.Dir("./public"))
 
     app.Get("/", func(ctx iris.Context) {
         ctx.View("upload.html")

_examples/dropzonejs/src/main.go

@@ -121,7 +121,7 @@ func main() {
 	app := iris.New()
 	app.RegisterView(iris.HTML("./views", ".html"))
 
-	app.HandleDir("/public", "./public")
+	app.HandleDir("/public", iris.Dir("./public"))
 
 	app.Get("/", func(ctx iris.Context) {
 		ctx.View("upload.html")

_examples/file-server/basic/main.go

@@ -12,11 +12,11 @@ func newApp() *iris.Application {
 	// first parameter is the request path
 	// second is the system directory
 	//
-	// app.HandleDir("/css", "./assets/css")
-	// app.HandleDir("/js", "./assets/js")
+	// app.HandleDir("/css", iris.Dir("./assets/css"))
+	// app.HandleDir("/js",  iris.Dir("./assets/js"))
 
 	v1 := app.Party("/v1")
-	v1.HandleDir("/static", "./assets", iris.DirOptions{
+	v1.HandleDir("/static", iris.Dir("./assets"), iris.DirOptions{
 		// 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
@@ -26,7 +26,19 @@ func newApp() *iris.Application {
 		Compress: false,
 		// List the files inside the current requested directory if `IndexName` not found.
 		ShowList: false,
-		// 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).
+		Cache: iris.DirCacheOptions{
+			// enable in-memory cache and pre-compress the files.
+			Enable: true,
+			// ignore image types (and pdf).
+			CompressIgnore: iris.MatchImagesAssets,
+			// do not compress files smaller than size.
+			CompressMinSize: 300,
+			// available encodings that will be negotiated with client's needs.
+			Encodings: []string{"gzip", "br" /* you can also add: deflate, snappy */},
+		},
+		DirList: iris.DirListRich(),
+		// 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).
 		// DirList: func(ctx iris.Context, dirName string, dir http.File) error { ... }
 		//
 		// Optional validator that loops through each requested resource.

_examples/file-server/basic/main_test.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/kataras/iris/v12"
 	"github.com/kataras/iris/v12/httptest"
 )
 
@@ -98,7 +99,7 @@ func TestHandleDirDot(t *testing.T) {
 		"/v1/assets.system/css/main.css",
 	}
 	app := newApp()
-	app.Subdomain("test").Party("/v1").HandleDir("/assets.system", "./assets.system")
+	app.Subdomain("test").Party("/v1").HandleDir("/assets.system", iris.Dir("./assets.system"))
 
 	e := httptest.New(t, app, httptest.URL("http://test.example.com"))
 	for _, u := range urls {