embed enhancement

README.md

@@ -1248,6 +1248,32 @@ func main() {
 }
 ```
 
+### Serving static files from embed
+
+```go
+// static
+// ├── css
+// │   └── chunk.css
+// ├── favicon.ico
+// ├── index.html
+// 
+//go:embed static
+var static embed.FS
+
+func main() {
+	router := gin.Default()
+	// /public/css/chunk.css
+	// /public/favicon.ico
+	// /public/index.html
+	router.StaticFSFromEmbed("/public/", "static/", static)
+	// /asset/chunk.css
+	router.StaticFSFromEmbed("/asset/", "static/css/", static)
+	// Listen and serve on 0.0.0.0:8080
+	router.Run(":8080")
+}
+
+```
+
 ### Serving data from file
 
 ```go

go.mod

@@ -1,6 +1,6 @@
 module github.com/gin-gonic/gin
 
-go 1.13
+go 1.16
 
 require (
 	github.com/gin-contrib/sse v0.1.0

routergroup.go

@@ -5,6 +5,8 @@
 package gin
 
 import (
+	"embed"
+	"io/fs"
 	"net/http"
 	"path"
 	"regexp"
@@ -36,6 +38,7 @@ type IRoutes interface {
 	OPTIONS(string, ...HandlerFunc) IRoutes
 	HEAD(string, ...HandlerFunc) IRoutes
 
+	StaticFSFromEmbed(relativePath, root string, assets embed.FS) IRoutes
 	StaticFile(string, string) IRoutes
 	Static(string, string) IRoutes
 	StaticFS(string, http.FileSystem) IRoutes
@@ -172,6 +175,33 @@ func (group *RouterGroup) Static(relativePath, root string) IRoutes {
 	return group.StaticFS(relativePath, Dir(root, false))
 }
 
+// Define redirectable embed fs interface
+type fsFunc func(name string) (fs.File, error)
+
+func (f fsFunc) Open(name string) (fs.File, error) {
+	return f(name)
+}
+
+// Redirectable embed files
+// use :
+//      //go:embed static
+//      var static embed.FS
+//      ......
+//      router.StaticFSFromEmbed("/", "static/", static)
+func (group *RouterGroup) StaticFSFromEmbed(relativePath, root string, assets embed.FS) IRoutes {
+	fs := http.FS(fsFunc(func(name string) (fs.File, error) {
+		assetPath := path.Join(root, name)
+		// If we can't find the asset, fs can handle the error
+		file, err := assets.Open(assetPath)
+		if err != nil {
+			return nil, err
+		}
+		// Otherwise assume this is a legitimate request routed correctly
+		return file, err
+	}))
+	return group.StaticFS(relativePath, fs)
+}
+
 // StaticFS works just like `Static()` but a custom `http.FileSystem` can be used instead.
 // Gin by default user: gin.Dir()
 func (group *RouterGroup) StaticFS(relativePath string, fs http.FileSystem) IRoutes {

routergroup_test.go

@@ -5,6 +5,7 @@
 package gin
 
 import (
+	"embed"
 	"net/http"
 	"testing"
 
@@ -162,6 +163,9 @@ func TestRouterGroupPipeline(t *testing.T) {
 	testRoutesInterface(t, v1)
 }
 
+//go:embed testdata
+var embed_static embed.FS
+
 func testRoutesInterface(t *testing.T, r IRoutes) {
 	handler := func(c *Context) {}
 	assert.Equal(t, r, r.Use(handler))
@@ -179,4 +183,5 @@ func testRoutesInterface(t *testing.T, r IRoutes) {
 	assert.Equal(t, r, r.StaticFile("/file", "."))
 	assert.Equal(t, r, r.Static("/static", "."))
 	assert.Equal(t, r, r.StaticFS("/static2", Dir(".", false)))
+	assert.Equal(t, r, r.StaticFSFromEmbed("/static3", "testdata", embed_static))
 }