SAK-40861 use the browser visibility state to avoid fetches when hidd…

…en and to fetch as soon as we are visible again
ottenhoff · Oct 31, 2018 · 78656f6 · 78656f6
1 parent aab3c31
commit 78656f6
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Showing 3 changed files with 31 additions and 10 deletions.
diff --git a/chat/chat-impl/impl/src/java/org/sakaiproject/chat2/model/impl/ChatManagerImpl.java b/chat/chat-impl/impl/src/java/org/sakaiproject/chat2/model/impl/ChatManagerImpl.java
@@ -194,7 +194,7 @@ protected void init() throws Exception
                     .build();
             heartbeatMap = CacheBuilder.newBuilder()
             		//.recordStats()
-            		.expireAfterAccess(pollInterval*2, TimeUnit.MILLISECONDS)
+            		.expireAfterWrite(1, TimeUnit.HOURS)
             		.build();
 
             timezoneCache = CacheBuilder.newBuilder()
@@ -1362,7 +1362,7 @@ private TransferableChatMessage addHeartBeat(String channelId, String sessionKey
             ret = TransferableChatMessage.HeartBeat(channelId, sessionKey);
             heartbeatMap.get(channelId, () -> {
                 return CacheBuilder.newBuilder()
-                        .expireAfterWrite(pollInterval*2, TimeUnit.MILLISECONDS)
+                        .expireAfterWrite(1, TimeUnit.HOURS)
                         .build();
             }).put(sessionId, ret);
         } catch(Exception e){
@@ -1382,8 +1382,12 @@ private boolean isOnline(String channelId, String sessionId) {
             return false;
         }
 
-        //thanks to the cache auto-expiration system, not updated hearbeats will be automatically removed
-        return (heartbeatMap.getIfPresent(channelId).getIfPresent(sessionId) != null);
+        // Check to see how active the user has been
+        TransferableChatMessage userHeartbeat = heartbeatMap.getIfPresent(channelId).getIfPresent(sessionId);
+        long timeDiff = ((new Date()).getTime()) - userHeartbeat.getTimestamp();
+        log.debug("Heartbeat diff for {} is {}; interval={}", sessionId, timeDiff, pollInterval*2);
+        // Safari seems to back off on setTimeout calls when in background for 60 seconds
+        return timeDiff <= 60000 + (pollInterval*2);
     }
 
     private void sendToCluster(TransferableChatMessage message){

diff --git a/.../chat-impl/impl/src/java/org/sakaiproject/chat2/model/impl/ChatMessageEntityProvider.java b/.../chat-impl/impl/src/java/org/sakaiproject/chat2/model/impl/ChatMessageEntityProvider.java
@@ -318,14 +318,13 @@ public Map<String,Object> handleChatData(EntityReference ref, Map<String,Object>
 			log.debug("No siteId specified");
 			throw new SecurityException("You must be specify the site ID");
 		}
-		log.debug("siteId: {}", siteId);
 
 		String channelId = (String) params.get("channelId");
 		if (StringUtils.isBlank(channelId)) {
 			log.debug("No channelId specified");
 			throw new SecurityException("You must be specify the channel ID");
 		}
-		log.debug("channelId: {}", channelId);
+		log.debug("channelId: {}, siteId: {}, sessionKey: {}", channelId, siteId, chatManager.getSessionKey());
 
 		ChatChannel channel = chatManager.getChatChannel(channelId);
 		if (!chatManager.getCanReadMessage(channel)) {

diff --git a/chat/chat-tool/tool/src/webapp/js/chatscript.js b/chat/chat-tool/tool/src/webapp/js/chatscript.js
@@ -18,13 +18,22 @@
  * limitations under the License.
  *
  **********************************************************************************/
+
+// When user goes between tabs or back from home screen, we monitor and updateChatData
+document.addEventListener('visibilitychange', function() {
+  if (document.visibilityState == 'hidden' || document.visibilityState == 'visible') {
+    chatscript.changePageVisibility(document.visibilityState);
+  }
+});
+
 var chatscript = {
 	url_submit : "/direct/chat-message/",
 	keycode_enter : 13,
 	pollInterval : 5000,
 	currentChatChannelId : null,
 	timeoutVar : null,
-
+	pageVisibility : 'visible',
+
 	init : function(){
 		var me = this;
 
@@ -101,6 +110,12 @@ var chatscript = {
 			});
 		});
 	},
+  changePageVisibility : function(newVisibility) {
+    this.pageVisibility = newVisibility;
+    if (newVisibility == 'visible') {
+      this.updateChatData();
+    }
+  },
 	sendMessage : function(params, textarea, submitButton) {
 		var me = this;
 		var errorSubmit = $("#errorSubmit");
@@ -143,9 +158,12 @@ var chatscript = {
 		if(this.timeoutVar != null) {
 			clearTimeout(this.timeoutVar);
 		}
-		this.timeoutVar = setTimeout(function() {
-			me.updateChatData();
-		}, this.pollInterval);
+		// If the tab is hidden, no use in firing AJAX requests for new chat data
+		if(this.pageVisibility != 'hidden') {
+			this.timeoutVar = setTimeout(function() {
+				me.updateChatData();
+			}, this.pollInterval);
+		}
 	},
 	doUpdateChatData : function() {
 		var me = this;