Add Context.SendFile to send a file to browser

CHANGELOG.md

@@ -10,6 +10,7 @@ under development
 - Add Context.ServeFile: a shortcut of http.ServeFile.
 - Add Context.ServeContent: a shortcut of http.ServeContent.
 - Add Context.BasicAuth: a shortcut of http.Request.BasicAuth.
+- Add Context.SendFile: sends a file to browser.
 
 v1.9.0 April 4, 2020
 --------------------

context.go

@@ -9,6 +9,7 @@ import (
 	"context"
 	"encoding/json"
 	"encoding/xml"
+	"fmt"
 	"io"
 	"net/http"
 	"net/url"
@@ -390,3 +391,10 @@ func (ctx *Context) RouteURL(name string, args ...string) (*url.URL, error) {
 func (ctx *Context) BasicAuth() (username, password string, ok bool) {
 	return ctx.Request.BasicAuth()
 }
+
+// SendFile sends a file to browser.
+func (ctx *Context) SendFile(filename string, r io.Reader) (err error) {
+	ctx.Response.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
+	_, err = io.Copy(ctx.Response, r)
+	return
+}

context_test.go

@@ -685,3 +685,12 @@ func TestContext_BasicAuth(t *testing.T) {
 		assert.Equal(t, ok1, ok2)
 	}
 }
+
+func TestContext_SendFile(t *testing.T) {
+	w := httptest.NewRecorder()
+	ctx := newContext(w, nil)
+	buf := bytes.NewReader([]byte("bar"))
+	ctx.SendFile("foo.txt", buf)
+	assert.Equal(t, "bar", w.Body.String())
+	assert.Equal(t, w.Header().Get("Content-Disposition"), `attachment; filename="foo.txt"`)
+}