Allow get feed by tag

main.go

@@ -130,7 +130,46 @@ func core() {
 			return item.Content, nil
 		},
 		func(tag string) (string, error) {
-			return "", errors.New("not implemented")
+			feedNames, err := sclient.List(nsForFeeds, "", false, -1)
+			if err != nil {
+				return "", err
+			}
+			combinedItems := []*rss.Item{}
+			for _, feedName := range feedNames {
+				b, err := 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 {
+						itemKeys, err := sclient.List(feed.ID(), "", false, 20) // TODO variable, or pick most recent n or something
+						if err != nil {
+							return "", err
+						}
+						for i := range itemKeys {
+							b, err := sclient.Get(feed.ID(), itemKeys[i])
+							if err != nil {
+								return "", errors.New("cannot get feed item " + itemKeys[i])
+							}
+							item, err := rss.DeserializeItem(b)
+							if err != nil {
+								return "", errors.New("cannot deserialize feed item" + itemKeys[i])
+							}
+							combinedItems = append(combinedItems, item)
+						}
+						break
+					}
+				}
+			}
+			combinedFeed, err := rss.New(tag, "", "", nil, time.Minute)
+			if err != nil {
+				return "", err
+			}
+			return rss.ToRSS(combinedFeed, combinedItems)
 		},
 	)
 	if err != nil {

main_test.go

@@ -18,6 +18,7 @@ func Test_Core(t *testing.T) {
 	server := httptest.NewUnstartedServer(nil)
 	server.Close()
 
+	var rssserverURL *string
 	rssserver := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path == "/feed" {
 			fmt.Fprintln(w,
@@ -25,17 +26,17 @@ func Test_Core(t *testing.T) {
                <?xml version="1.0" encoding="utf-8"?>
                <rss version="2.0"><channel>
                   <title>fake.com</title>
-                  <link>/feed</link>
+                  <link>`+*rssserverURL+`/feed</link>
                   <description>this is fake</description>
                   <item>
                      <title>title A</title>
-                     <link>/itemA</link>
+                     <link>`+*rssserverURL+`/itemA</link>
                      <description></description>
                      <pubDate>Wed, 10 Oct 2018 04:00:00 -0000</pubDate>
                   </item>
                   <item>
                      <title>title B</title>
-                     <link>/itemB</link>
+                     <link>`+*rssserverURL+`/itemB</link>
                      <description>content B</description>
                      <pubDate>Wed, 10 Oct 2018 04:00:00 -0000</pubDate>
                   </item>
@@ -51,6 +52,7 @@ func Test_Core(t *testing.T) {
 		}
 	}))
 	defer server.Close()
+	rssserverURL = &rssserver.URL
 
 	wasDBPath := os.Getenv("DBPATH")
 	wasPort := os.Getenv("PORT")
@@ -82,7 +84,7 @@ func Test_Core(t *testing.T) {
 		{
 			method: "post",
 			path:   "api/feed",
-			body:   `{"url":"` + rssserver.URL + `/feed", "refresh":"30m", "items":"[AB]", "content":"2"}`,
+			body:   `{"url":"` + rssserver.URL + `/feed", "refresh":"30m", "items":"[AB]", "content":"2", "tags": ["gotest"]}`,
 			status: 200,
 			post:   func() { time.Sleep(time.Second * 10) },
 		},
@@ -95,7 +97,12 @@ func Test_Core(t *testing.T) {
 		{
 			method: "get",
 			path:   "api/feed/item",
-			body:   "http___127_0_0_1_" + strings.Split(rssserver.URL, ":")[2] + "_feed.20181010__itemB",
+			body:   "http___127_0_0_1_" + strings.Split(rssserver.URL, ":")[2] + "_feed.20181010_http___127_0_0_1_" + strings.Split(rssserver.URL, ":")[2] + "_itemB",
+			status: 200,
+		},
+		{
+			method: "get",
+			path:   "api/feed/tag?url=gotest",
 			status: 200,
 		},
 		{
@@ -134,7 +141,7 @@ func Test_Core(t *testing.T) {
 		} else if b, err := ioutil.ReadAll(resp.Body); err != nil {
 			t.Errorf("cannot read body on %s to %s: %v", c.method, loc.String(), err)
 		} else {
-			t.Logf("resp body: %s", b)
+			t.Logf("%s resp body: %s", loc.String(), b)
 		}
 		if c.post != nil {
 			c.post()