Set PerThreadCache as readonly after creating a new patch-set

Apply the same optimisation made for Change-Id: I1b71bfcf to
the production of events after creating a new patch-set  and for returning
the merged change JSON response.

The same considerations of performance improvement and reduction
of /meta refs lookup are valid in this use-case.

Release-Notes: enable the read-only cache of /meta refs for new patch-sets
Change-Id: I58abd12f3779e0a57c1f8cda618905c9c0bb9b7e

2 files changed, 23 insertions, 14 deletions

diff --git a/java/com/google/gerrit/server/events/StreamEventsApiListener.java b/java/com/google/gerrit/server/events/StreamEventsApiListener.java
index 6a530ed764..d009387861 100644
--- a/java/com/google/gerrit/server/events/StreamEventsApiListener.java
+++ b/java/com/google/gerrit/server/events/StreamEventsApiListener.java
@@ -291,14 +291,18 @@ public class StreamEventsApiListener
   @Override
   public void onRevisionCreated(RevisionCreatedListener.Event ev) {
     try {
-      ChangeNotes notes = getNotes(ev.getChange());
-      Change change = notes.getChange();
-      PatchSet patchSet = getPatchSet(notes, ev.getRevision());
-      PatchSetCreatedEvent event = new PatchSetCreatedEvent(change);
+      Change change;
+      PatchSetCreatedEvent event;
+      try (ReadonlyRequestWindow window = PerThreadCache.openReadonlyRequestWindow()) {
+        ChangeNotes notes = getNotes(ev.getChange());
+        change = notes.getChange();
+        PatchSet patchSet = getPatchSet(notes, ev.getRevision());
+        event = new PatchSetCreatedEvent(change);
 
-      event.change = changeAttributeSupplier(change, notes);
-      event.patchSet = patchSetAttributeSupplier(change, patchSet);
-      event.uploader = accountAttributeSupplier(ev.getWho());
+        event.change = changeAttributeSupplier(change, notes);
+        event.patchSet = patchSetAttributeSupplier(change, patchSet);
+        event.uploader = accountAttributeSupplier(ev.getWho());
+      }
 
       dispatcher.run(d -> d.postEvent(change, event));
     } catch (OrmException e) {
diff --git a/java/com/google/gerrit/server/extensions/events/RevisionCreated.java b/java/com/google/gerrit/server/extensions/events/RevisionCreated.java
index e043e9fcd2..cb4d0b4a89 100644
--- a/java/com/google/gerrit/server/extensions/events/RevisionCreated.java
+++ b/java/com/google/gerrit/server/extensions/events/RevisionCreated.java
@@ -24,6 +24,8 @@ import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.server.GpgException;
 import com.google.gerrit.server.account.AccountState;
+import com.google.gerrit.server.cache.PerThreadCache;
+import com.google.gerrit.server.cache.PerThreadCache.ReadonlyRequestWindow;
 import com.google.gerrit.server.patch.PatchListNotAvailableException;
 import com.google.gerrit.server.patch.PatchListObjectTooLargeException;
 import com.google.gerrit.server.permissions.PermissionBackendException;
@@ -73,13 +75,16 @@ public class RevisionCreated {
       return;
     }
     try {
-      Event event =
-          new Event(
-              util.changeInfo(change),
-              util.revisionInfo(change.getProject(), patchSet),
-              util.accountInfo(uploader),
-              when,
-              notify);
+      Event event;
+      try (ReadonlyRequestWindow window = PerThreadCache.openReadonlyRequestWindow()) {
+        event =
+            new Event(
+                util.changeInfo(change),
+                util.revisionInfo(change.getProject(), patchSet),
+                util.accountInfo(uploader),
+                when,
+                notify);
+      }
       listeners.runEach(l -> l.onRevisionCreated(event));
     } catch (PatchListObjectTooLargeException e) {
       logger.atWarning().log("Couldn't fire event: %s", e.getMessage());