From 74a9a408e6553c8d047e1f138e9030cea52f41b1 Mon Sep 17 00:00:00 2001
From: Acconut <maerious@gmail.com>
Date: Tue, 3 Feb 2015 19:01:35 +0100
Subject: [PATCH] add metadata extension

---
 handler.go      | 36 +++++++++++++++++++++++++++++++++---
 handler_test.go | 16 +++++++++++++++-
 2 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/handler.go b/handler.go
index 705d37e..9892525 100644
--- a/handler.go
+++ b/handler.go
@@ -1,6 +1,7 @@
 package tusd
 
 import (
+	"encoding/base64"
 	"errors"
 	"io"
 	"log"
@@ -8,6 +9,7 @@ import (
 	"net/url"
 	"os"
 	"strconv"
+	"strings"
 
 	"github.com/bmizerany/pat"
 )
@@ -127,7 +129,7 @@ func (handler *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		}
 
 		header.Set("TUS-Version", "1.0.0")
-		header.Set("TUS-Extension", "file-creation")
+		header.Set("TUS-Extension", "file-creation,metadata")
 
 		w.WriteHeader(http.StatusNoContent)
 		return
@@ -158,8 +160,8 @@ func (handler *Handler) postFile(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// @TODO: implement metadata extension
-	meta := make(map[string]string)
+	// Parse metadata
+	meta := parseMeta(r.Header.Get("Metadata"))
 
 	id, err := handler.dataStore.NewUpload(size, meta)
 	if err != nil {
@@ -285,3 +287,31 @@ func (handler *Handler) absFileUrl(r *http.Request, id string) string {
 
 	return url
 }
+
+// Parse the meatadata as defined in the Metadata extension.
+// e.g. Metadata: key base64value, key2 base64value
+func parseMeta(header string) map[string]string {
+	meta := make(map[string]string)
+
+	for _, element := range strings.Split(header, ",") {
+		element := strings.TrimSpace(element)
+
+		parts := strings.Split(element, " ")
+
+		// Do not continue with this element if no key and value or presented
+		if len(parts) != 2 {
+			continue
+		}
+
+		// Ignore corrent element if the value is no valid base64
+		key := parts[0]
+		value, err := base64.StdEncoding.DecodeString(parts[1])
+		if err != nil {
+			continue
+		}
+
+		meta[key] = string(value)
+	}
+
+	return meta
+}
diff --git a/handler_test.go b/handler_test.go
index ea6dc03..d33b880 100644
--- a/handler_test.go
+++ b/handler_test.go
@@ -80,7 +80,7 @@ func TestProtocolDiscovery(t *testing.T) {
 	}
 
 	headers := map[string]string{
-		"TUS-Extension": "file-creation",
+		"TUS-Extension": "file-creation,metadata",
 		"TUS-Version":   "1.0.0",
 		"TUS-Resumable": "1.0.0",
 		"TUS-Max-Size":  "400",
@@ -110,6 +110,19 @@ func (s postStore) NewUpload(size int64, metaData MetaData) (string, error) {
 	if size != 300 {
 		s.t.Errorf("Expected size to be 300 (got %v)", size)
 	}
+
+	if len(metaData) != 2 {
+		s.t.Errorf("Expected two elements in metadata")
+	}
+
+	if v := metaData["foo"]; v != "hello" {
+		s.t.Errorf("Expected foo element to be 'hello' but got %s", v)
+	}
+
+	if v := metaData["bar"]; v != "world" {
+		s.t.Errorf("Expected bar element to be 'world' but got %s", v)
+	}
+
 	return "foo", nil
 }
 
@@ -126,6 +139,7 @@ func TestFileCreation(t *testing.T) {
 	req, _ := http.NewRequest("POST", "", nil)
 	req.Header.Set("TUS-Resumable", "1.0.0")
 	req.Header.Set("Entity-Length", "300")
+	req.Header.Set("Metadata", "foo aGVsbG8=, bar d29ybGQ=")
 	req.Host = "tus.io"
 	w := httptest.NewRecorder()
 	handler.ServeHTTP(w, req)