ReviewerAddedListener: Notify multiple reviewers added in same event

When multiple reviewers were added to a change, notify them all with
a single event and let listeners act on each individual reviewer as
necessary.

This change is needed to allow splitting the mail notifications to a
listener.

Change-Id: I8b1f3918877b9635a6592beae6ad5aeea0a5adce

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/events/ReviewerAddedListener.java

@@ -17,12 +17,14 @@ package com.google.gerrit.extensions.events;
 import com.google.gerrit.extensions.annotations.ExtensionPoint;
 import com.google.gerrit.extensions.common.AccountInfo;
 
-/** Notified whenever a Reviewer is added to a change. */
+import java.util.List;
+
+/** Notified whenever one or more Reviewers are added to a change. */
 @ExtensionPoint
 public interface ReviewerAddedListener {
   interface Event extends ChangeEvent {
-    AccountInfo getReviewer();
+    List<AccountInfo> getReviewers();
   }
 
-  void onReviewerAdded(Event event);
+  void onReviewersAdded(Event event);
 }

gerrit-server/src/main/java/com/google/gerrit/server/change/PostReviewers.java

@@ -17,6 +17,7 @@ package com.google.gerrit.server.change;
 import static com.google.gerrit.extensions.client.ReviewerState.CC;
 import static com.google.gerrit.extensions.client.ReviewerState.REVIEWER;
 
+import com.google.common.base.Function;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
@@ -40,7 +41,6 @@ import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PatchSetUtil;
-import com.google.gerrit.server.account.AccountCache;
 import com.google.gerrit.server.account.AccountLoader;
 import com.google.gerrit.server.account.AccountsCollection;
 import com.google.gerrit.server.account.GroupMembers;
@@ -96,7 +96,6 @@ public class PostReviewers
   private final Provider<IdentifiedUser> user;
   private final IdentifiedUser.GenericFactory identifiedUserFactory;
   private final Config cfg;
-  private final AccountCache accountCache;
   private final ReviewerJson json;
   private final ReviewerAdded reviewerAdded;
   private final NotesMigration migration;
@@ -115,7 +114,6 @@ public class PostReviewers
       Provider<IdentifiedUser> user,
       IdentifiedUser.GenericFactory identifiedUserFactory,
       @GerritServerConfig Config cfg,
-      AccountCache accountCache,
       ReviewerJson json,
       ReviewerAdded reviewerAdded,
       NotesMigration migration) {
@@ -132,7 +130,6 @@ public class PostReviewers
     this.user = user;
     this.identifiedUserFactory = identifiedUserFactory;
     this.cfg = cfg;
-    this.accountCache = accountCache;
     this.json = json;
     this.reviewerAdded = reviewerAdded;
     this.migration = migration;
@@ -355,11 +352,15 @@ public class PostReviewers
         }
         emailReviewers(rsrc.getChange(), addedReviewers, addedCCs);
         if (!addedReviewers.isEmpty()) {
-          for (PatchSetApproval psa : addedReviewers) {
-            Account account = accountCache.get(psa.getAccountId()).getAccount();
-            reviewerAdded.fire(rsrc.getChange(), patchSet, account,
-              ctx.getAccount(), ctx.getWhen());
+          List<Account.Id> reviewers = Lists.transform(addedReviewers,
+              new Function<PatchSetApproval, Account.Id>() {
+                @Override
+                public Account.Id apply(PatchSetApproval psa) {
+                  return psa.getAccountId();
                 }
+              });
+          reviewerAdded.fire(rsrc.getChange(), patchSet, reviewers,
+              ctx.getAccount(), ctx.getWhen());
         }
       }
     }

gerrit-server/src/main/java/com/google/gerrit/server/events/StreamEventsApiListener.java

@@ -321,7 +321,7 @@ public class StreamEventsApiListener implements
   }
 
   @Override
-  public void onReviewerAdded(ReviewerAddedListener.Event ev) {
+  public void onReviewersAdded(ReviewerAddedListener.Event ev) {
     try {
       ChangeNotes notes = getNotes(ev.getChange());
       Change change = notes.getChange();
@@ -330,9 +330,10 @@ public class StreamEventsApiListener implements
       event.change = changeAttributeSupplier(change);
       event.patchSet = patchSetAttributeSupplier(change,
           psUtil.current(db.get(), notes));
-      event.reviewer = accountAttributeSupplier(ev.getReviewer());
-
+      for (AccountInfo reviewer : ev.getReviewers()) {
+        event.reviewer = accountAttributeSupplier(reviewer);
         dispatcher.get().postEvent(change, event);
+      }
     } catch (OrmException e) {
       log.error("Failed to dispatch event", e);
     }

gerrit-server/src/main/java/com/google/gerrit/server/extensions/events/ReviewerAdded.java

@@ -15,6 +15,8 @@
 package com.google.gerrit.server.extensions.events;
 
 import com.google.gerrit.extensions.api.changes.NotifyHandling;
+import com.google.common.base.Function;
+import com.google.common.collect.Lists;
 import com.google.gerrit.extensions.common.AccountInfo;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.RevisionInfo;
@@ -33,6 +35,7 @@ import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.sql.Timestamp;
+import java.util.List;
 
 public class ReviewerAdded {
   private static final Logger log =
@@ -49,29 +52,38 @@ public class ReviewerAdded {
   }
 
   public void fire(ChangeInfo change, RevisionInfo revision,
-      AccountInfo reviewer, AccountInfo adder, Timestamp when) {
+      List<AccountInfo> reviewers, AccountInfo adder, Timestamp when) {
     if (!listeners.iterator().hasNext()) {
       return;
     }
-    Event event = new Event(change, revision, reviewer, adder, when);
+    Event event = new Event(change, revision, reviewers, adder, when);
     for (ReviewerAddedListener l : listeners) {
       try {
-        l.onReviewerAdded(event);
+        l.onReviewersAdded(event);
       } catch (Exception e) {
         log.warn("Error in event listener, e");
       }
     }
   }
 
-  public void fire(Change change, PatchSet patchSet, Account account,
+  public void fire(Change change, PatchSet patchSet, List<Account.Id> reviewers,
       Account adder, Timestamp when) {
-    if (!listeners.iterator().hasNext()) {
+    if (!listeners.iterator().hasNext() || reviewers.isEmpty()) {
       return;
     }
+
+    List<AccountInfo> transformed = Lists.transform(reviewers,
+        new Function<Account.Id, AccountInfo>() {
+          @Override
+          public AccountInfo apply(Account.Id account) {
+            return util.accountInfo(account);
+          }
+        });
+
     try {
       fire(util.changeInfo(change),
           util.revisionInfo(change.getProject(), patchSet),
-          util.accountInfo(account),
+          transformed,
           util.accountInfo(adder),
           when);
     } catch (PatchListNotAvailableException | GpgException | IOException
@@ -82,17 +94,17 @@ public class ReviewerAdded {
 
   private static class Event extends AbstractRevisionEvent
       implements ReviewerAddedListener.Event {
-    private final AccountInfo reviewer;
+    private final List<AccountInfo> reviewers;
 
-    Event(ChangeInfo change, RevisionInfo revision, AccountInfo reviewer,
+    Event(ChangeInfo change, RevisionInfo revision, List<AccountInfo> reviewers,
         AccountInfo adder, Timestamp when) {
       super(change, revision, adder, when, NotifyHandling.ALL);
-      this.reviewer = reviewer;
+      this.reviewers = reviewers;
     }
 
     @Override
-    public AccountInfo getReviewer() {
-      return reviewer;
+    public List<AccountInfo> getReviewers() {
+      return reviewers;
     }
   }
 }