add api/list/tag/tag_name_here

exchange/exchange.go

@@ -112,6 +112,32 @@ func (ex *Exchange) GetFeedItem(ID string) (string, error) {
 	return item.Content, nil
 }
 
+func (ex *Exchange) ListTag(tag string, n int) (string, error) {
+	feeds := []*rss.Feed{}
+	feedNames, err := ex.SClient.List(nsForFeeds, "", true, -1)
+	if err != nil {
+		return "", err
+	}
+	for _, feedName := range feedNames {
+		b, err := ex.SClient.Get(nsForFeeds, feedName)
+		if err != nil {
+			return "", err
+		}
+		feed, err := rss.Deserialize(b)
+		if err != nil {
+			return "", err
+		}
+
+		for i := range feed.Tags {
+			if feed.Tags[i] == tag {
+				feeds = append(feeds, feed)
+			}
+		}
+	}
+	b, err := json.Marshal(feeds)
+	return string(b), err
+}
+
 func (ex *Exchange) GetFeedTagRSS(tag string) (string, error) {
 	feedNames, err := ex.SClient.List(nsForFeeds, "", true, -1)
 	if err != nil {

main.go

@@ -42,6 +42,7 @@ func core() {
 		ex.GetFeedRSS,
 		ex.GetFeedItem,
 		ex.GetFeedTagRSS,
+		ex.ListTag,
 	); err != nil {
 		panic(err)
 	}

main_test.go

@@ -110,6 +110,11 @@ func Test_Core(t *testing.T) {
 			status: 200,
 			post:   func() { time.Sleep(time.Second * 15) },
 		},
+		{
+			method: "get",
+			path:   "api/list/tag/gotest",
+			status: 200,
+		},
 	}
 	for _, c := range cases {
 		c.method = strings.ToUpper(c.method)

server/server.go

@@ -22,15 +22,24 @@ type Server struct {
 	getFeedHandler     func(string, int) (string, error)
 	getFeedItemHandler func(string) (string, error)
 	getFeedTagHandler  func(string) (string, error)
+	getListTagHandler  func(string, int) (string, error)
 }
 
-func New(addr string, newFeedHandler func(string, string, string, []string, time.Duration), getFeedHandler func(string, int) (string, error), getFeedItemHandler func(string) (string, error), getFeedTagHandler func(string) (string, error)) (*Server, error) {
+func New(
+	addr string,
+	newFeedHandler func(string, string, string, []string, time.Duration),
+	getFeedHandler func(string, int) (string, error),
+	getFeedItemHandler func(string) (string, error),
+	getFeedTagHandler func(string) (string, error),
+	getListTagHandler func(string, int) (string, error),
+) (*Server, error) {
 	return &Server{
 		addr:               addr,
 		newFeedHandler:     newFeedHandler,
 		getFeedHandler:     getFeedHandler,
 		getFeedItemHandler: getFeedItemHandler,
 		getFeedTagHandler:  getFeedTagHandler,
+		getListTagHandler:  getListTagHandler,
 	}, nil
 }
 
@@ -81,6 +90,8 @@ func (s *Server) api(w http.ResponseWriter, r *http.Request) {
 	switch advance(r) {
 	case "feed":
 		s.feed(w, r)
+	case "list":
+		s.list(w, r)
 	default:
 		s.notFound(w, r)
 	}
@@ -198,6 +209,24 @@ func (s *Server) getFeed(w http.ResponseWriter, r *http.Request) {
 	fmt.Fprintln(w, feedBody)
 }
 
+func (s *Server) list(w http.ResponseWriter, r *http.Request) {
+	switch advance(r) {
+	case "tag":
+		s.listTag(w, r)
+	default:
+		s.notFound(w, r)
+	}
+}
+
+func (s *Server) listTag(w http.ResponseWriter, r *http.Request) {
+	tag := advance(r)
+	out, err := s.getListTagHandler(tag, -1)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Fprintln(w, out)
+}
+
 func validURL(loc string) bool {
 	_, err := url.ParseRequestURI(loc)
 	return err == nil

server/server_test.go

@@ -19,7 +19,7 @@ func Test_Server(t *testing.T) {
 	testPort = strings.Split(server.Listener.Addr().String(), ":")[1]
 
 	var err error
-	s, err := New(testPort, func(string, string, string, []string, time.Duration) {}, func(string, int) (string, error) { return "", nil }, func(string) (string, error) { return "", nil }, func(string) (string, error) { return "", nil })
+	s, err := New(testPort, func(string, string, string, []string, time.Duration) {}, func(string, int) (string, error) { return "", nil }, func(string) (string, error) { return "", nil }, func(string) (string, error) { return "", nil }, func(string, int) (string, error) { return "", nil })
 	if err != nil {
 		t.Errorf("failed to create server: %v", err)
 	}
@@ -58,6 +58,12 @@ func Test_Server(t *testing.T) {
 	if err := checkStatus("GET", "api/feed/tag/b", http.StatusOK); err != nil {
 		t.Errorf(err.Error())
 	}
+	if err := checkStatus("GET", "api/feed/tag/b", http.StatusOK); err != nil {
+		t.Errorf(err.Error())
+	}
+	if err := checkStatus("GET", "api/list/tag/b", http.StatusOK); err != nil {
+		t.Errorf(err.Error())
+	}
 	syscall.Kill(syscall.Getpid(), syscall.SIGINT)
 }