Add pinned posts (#4217)

store/sql_channel_store.go

@@ -321,6 +321,32 @@ func (s SqlChannelStore) Get(id string, allowFromCache bool) StoreChannel {
 	return s.get(id, false, allowFromCache)
 }
 
+func (s SqlChannelStore) GetPinnedPosts(channelId string) StoreChannel {
+	storeChannel := make(StoreChannel, 1)
+
+	go func() {
+		result := StoreResult{}
+		pl := &model.PostList{}
+
+		var posts []*model.Post
+		if _, err := s.GetReplica().Select(&posts, "SELECT * FROM Posts WHERE IsPinned = true AND ChannelId = :ChannelId AND DeleteAt = 0 ORDER BY CreateAt ASC", map[string]interface{}{"ChannelId": channelId}); err != nil {
+			result.Err = model.NewLocAppError("SqlPostStore.GetPinnedPosts", "store.sql_channel.pinned_posts.app_error", nil, err.Error())
+		} else {
+			for _, post := range posts {
+				pl.AddPost(post)
+				pl.AddOrder(post.Id)
+			}
+		}
+
+		result.Data = pl
+
+		storeChannel <- result
+		close(storeChannel)
+	}()
+
+	return storeChannel
+}
+
 func (s SqlChannelStore) GetFromMaster(id string) StoreChannel {
 	return s.get(id, true, false)
 }