Fix the Routing Error by Setting the isSessionAlive when open a sessi…

…on (#12737)

When we open a session in Deli LambdaFactory, we mark both
isSessionAlive and isSessionActive as true.

There is a session in cluster 1 that ends at time t0, another session
that starts at t0+4hrs, and a third session that begins at t0+4hrs+a
couple of mins.
In this case, when the last session reads the truth, the lastAccessTime
is > 3hrs (since session 2 is not finished and lastAccessTime is updated
only on the session end). This is fine but the strange thing is that we
are seeing that when session 3 reads the truth, it has
"isSessionAlive":false, and"isSessionActive":true. This should be a
"never" case. This is weird because we thought session 2 would have made
"isSessionAlive": true after it went through discovery.
We would like to introduce this fix to mark both isSessionAlive and
isSessionActive as true, when opening a session in the deli lambda
factory so that it would still use the urls stored in the truth.


![MicrosoftTeams-image](https://user-images.githubusercontent.com/66701969/199107141-492da277-9f6f-4524-befb-0c64f0198f55.png)

server/routerlicious/packages/lambdas/src/deli/lambdaFactory.ts

@@ -212,16 +212,21 @@ export class DeliLambdaFactory extends EventEmitter implements IPartitionLambdaF
             });
         });
 
-        // Fire-and-forget sessionActive update for session-boot performance.
+        // Fire-and-forget sessionAlive and sessionActive update for session-boot performance.
         // Worst case is that document is allowed to be deleted while active.
+        context.log?.info(
+            `Deli Lambda is marking session as alive and active as true.`,
+            { messageMetaData },
+        );
         this.collection.update(
             { documentId, tenantId },
             {
+                "session.isSessionAlive": true,
                 "session.isSessionActive": true,
             },
             null,
         ).catch((error) => {
-            const errMsg = "Deli Lambda failed to mark session as active.";
+            const errMsg = "Deli Lambda failed to mark session as alive and active.";
             context.log?.error(`${errMsg}. Exception: ${inspect(error)}`, { messageMetaData });
         });
 

server/routerlicious/packages/routerlicious-base/src/test/alfred/api.spec.ts

@@ -421,7 +421,7 @@ describe("Routerlicious", () => {
                                     historianUrl: defaultProvider.get("worker:blobStorageUrl"),
                                     deltaStreamUrl: defaultProvider.get("worker:deltaStreamUrl"),
                                     isSessionAlive: false,
-                                    isSessionActive: false
+                                    isSessionActive: true
                                 })
                             });
                     });

server/routerlicious/packages/routerlicious-base/src/utils/sessionHelper.ts

@@ -213,8 +213,8 @@ export async function getSession(
         return convertSessionToFreshSession(newSession, lumberjackProperties);
     }
 
-    if (existingSession.isSessionAlive) {
-        // Existing session is considered alive/discovered, so return to consumer as-is.
+    if (existingSession.isSessionAlive || existingSession.isSessionActive) {
+        // Existing session is considered alive/discovered or active, so return to consumer as-is.
         return existingSession;
     }