New iris.DirOptions.PushTargetsRegexp

rel to: #1562 (comment)

HISTORY.md

@@ -371,7 +371,20 @@ Other Improvements:
 
 ![DBUG routes](https://iris-go.com/images/v12.2.0-dbug2.png?v=0)
 
-- Fix [#1562](https://github.com/kataras/iris/issues/1562)
+- 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{
+        "/": regexp.MustCompile("((.*).js|(.*).css|(.*).ico)$"),
+        // OR:
+		// "/": iris.MatchCommonAssets,
+	},
+	Compress: true,
+}
+```
+
 - Update jet parser to v4.0.2, closes [#1551](https://github.com/kataras/iris/issues/1551). It contains two breaking changes by its author:
     - Relative paths on `extends, import, include...` tmpl functions, e.g. `{{extends "../layouts/application.jet"}}` instead of `layouts/application.jet`
     - the new [jet.Ranger](https://github.com/CloudyKit/jet/pull/165) interface now requires a `ProvidesIndex() bool` method too
@@ -380,7 +393,7 @@ Other Improvements:
 - Fix [#1552](https://github.com/kataras/iris/issues/1552).
 
 - Proper listing of root directories on `Party.HandleDir` when its `DirOptions.ShowList` was set to true.
-    - Customize the file/directory listing page through views, see [example](https://github.com/kataras/iris/tree/master/_examples/file-server/file-server)
+    - Customize the file/directory listing page through views, see [example](https://github.com/kataras/iris/tree/master/_examples/file-server/file-server).
 
 - Socket Sharding as requested at [#1544](https://github.com/kataras/iris/issues/1544). New `iris.WithSocketSharding` Configurator and `SocketSharding bool` setting.
 

_examples/file-server/http2push/main.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"regexp"
+
 	"github.com/kataras/iris/v12"
 )
 
@@ -13,13 +15,20 @@ var opts = iris.DirOptions{
 	//
 	// Note: Requires running server under TLS,
 	// that's why we use `iris.TLS` below.
-	PushTargets: map[string][]string{
-		"/": { // Relative path without route prefix.
-			"favicon.ico",
-			"js/main.js",
-			"css/main.css",
-			// ^ Relative to the index, if need absolute ones start with a slash ('/').
-		},
+	// PushTargets: map[string][]string{
+	// 	"/": { // Relative path without prefix.
+	// 		"favicon.ico",
+	// 		"js/main.js",
+	// 		"css/main.css",
+	// 		// ^ Relative to the index, if need absolute ones start with a slash ('/').
+	// 	},
+	// },
+	// OR use regexp:
+	PushTargetsRegexp: map[string]*regexp.Regexp{
+		// Match all js, css and ico files
+		// from all files (recursively).
+		// "/": regexp.MustCompile("((.*).js|(.*).css|(.*).ico)$"),
+		"/": iris.MatchCommonAssets,
 	},
 	Compress: true,
 	ShowList: true,

aliases.go

@@ -2,6 +2,7 @@ package iris
 
 import (
 	"net/http"
+	"regexp"
 
 	"github.com/kataras/iris/v12/cache"
 	"github.com/kataras/iris/v12/context"
@@ -216,6 +217,13 @@ var (
 		ctx.CompressReader(true)
 		ctx.Next()
 	}
+
+	// MatchCommonAssets is a simple regex expression which
+	// can be used on `DirOptions.PushTargetsRegexp`.
+	// It will match and Push
+	// all available js, css, font and media files.
+	// Ideal for Single Page Applications.
+	MatchCommonAssets = regexp.MustCompile("((.*).js|(.*).css|(.*).ico|(.*).png|(.*).ttf|(.*).svg|(.*).webp|(.*).gif)$")
 )
 
 var (

core/router/fs.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"regexp"
 	"sort"
 	"strings"
 	"time"
@@ -48,7 +49,23 @@ type DirOptions struct {
 	// 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
+
 	// When files should served under compression.
 	Compress bool
 
@@ -407,7 +424,11 @@ func FileServer(directory string, opts ...DirOptions) context.Handler {
 			return
 		}
 
-		indexFound := false
+		var (
+			indexFound     bool
+			indexDirectory http.File
+		)
+
 		// use contents of index.html for directory, if present
 		if info.IsDir() && options.IndexName != "" {
 			// Note that, in contrast of the default net/http mechanism;
@@ -425,9 +446,11 @@ func FileServer(directory string, opts ...DirOptions) context.Handler {
 				defer fIndex.Close()
 				infoIndex, err := fIndex.Stat()
 				if err == nil {
-					info = infoIndex
-					f = fIndex
 					indexFound = true
+					indexDirectory = f
+
+					f = fIndex
+					info = infoIndex
 				}
 			}
 		}
@@ -454,6 +477,25 @@ func FileServer(directory string, opts ...DirOptions) context.Handler {
 					}
 				}
 			}
+
+			if regex, ok := options.PushTargetsRegexp[r.URL.Path]; ok {
+				if pusher, ok := ctx.ResponseWriter().(http.Pusher); ok {
+					for _, indexAsset := range getFilenamesRecursively(fs, indexDirectory, "") {
+						// it's an index file, do not pushed that.
+						if strings.HasSuffix("/"+indexAsset, options.IndexName) {
+							continue
+						}
+						// match using relative path (without the first '/' slash)
+						// to keep consistency between the `PushTargets` behavior
+						if regex.MatchString(indexAsset) {
+							// println("Regex Matched: " + indexAsset)
+							if err = pusher.Push(path.Join(r.RequestURI, indexAsset), nil); err != nil {
+								break
+							}
+						}
+					}
+				}
+			}
 		}
 
 		// Still a directory? (we didn't find an index.html file)
@@ -532,6 +574,38 @@ func FileServer(directory string, opts ...DirOptions) context.Handler {
 	return h
 }
 
+func getFilenamesRecursively(fs http.FileSystem, f http.File, parent string) []string {
+	defer f.Close()
+	info, err := f.Stat()
+	if err != nil {
+		return nil
+	}
+
+	var filenames []string
+
+	if info.IsDir() {
+		fileinfos, err := f.Readdir(-1)
+		if err != nil {
+			return nil
+		}
+
+		for _, fileinfo := range fileinfos {
+			fullname := path.Join(parent, fileinfo.Name())
+			ff, err := fs.Open(fullname)
+			if err != nil {
+				return nil
+			}
+
+			filenames = append(filenames, getFilenamesRecursively(fs, ff, fullname)...)
+		}
+
+		return filenames
+	}
+
+	filenames = append(filenames, path.Dir(path.Join(parent, info.Name())))
+	return filenames
+}
+
 // StripPrefix returns a handler that serves HTTP requests
 // by removing the given prefix from the request URL's Path
 // and invoking the handler h. StripPrefix handles a