ReviewerApi: Add method to remove the reviewer

Change-Id: I7ad74f64a3b17d5f5209bedf7c8afb4b907146ba

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/api/change/ChangeIT.java

@@ -520,6 +520,7 @@ public class ChangeIT extends AbstractDaemonTest {
   @Test
   public void addReviewer() throws Exception {
     TestTimeUtil.resetWithClockStep(1, SECONDS);
+    sender.clear();
     PushOneCommit.Result r = createChange();
     ChangeResource rsrc = parseResource(r);
     String oldETag = rsrc.getETag();
@@ -646,6 +647,49 @@ public class ChangeIT extends AbstractDaemonTest {
     assertThat(m).containsEntry("Code-Review", Short.valueOf((short)-1));
   }
 
+  @Test
+  public void removeReviewer() throws Exception {
+    PushOneCommit.Result r = createChange();
+    String changeId = r.getChangeId();
+    gApi.changes()
+        .id(changeId)
+        .revision(r.getCommit().name())
+        .review(ReviewInput.approve());
+
+    setApiUser(user);
+    gApi.changes()
+        .id(changeId)
+        .revision(r.getCommit().name())
+        .review(ReviewInput.recommend());
+
+    Collection<AccountInfo> reviewers = gApi.changes()
+        .id(changeId)
+        .get()
+        .reviewers.get(REVIEWER);
+
+    assertThat(reviewers).hasSize(2);
+    Iterator<AccountInfo> reviewerIt = reviewers.iterator();
+    assertThat(reviewerIt.next()._accountId)
+        .isEqualTo(admin.getId().get());
+    assertThat(reviewerIt.next()._accountId)
+        .isEqualTo(user.getId().get());
+
+    setApiUser(admin);
+    gApi.changes()
+        .id(changeId)
+        .reviewer(user.getId().toString())
+        .remove();
+
+    reviewers = gApi.changes()
+        .id(changeId)
+        .get()
+        .reviewers.get(REVIEWER);
+    assertThat(reviewers).hasSize(1);
+    reviewerIt = reviewers.iterator();
+    assertThat(reviewerIt.next()._accountId)
+      .isEqualTo(admin.getId().get());
+  }
+
   @Test
   public void deleteVote() throws Exception {
     PushOneCommit.Result r = createChange();

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/changes/ReviewerApi.java

@@ -23,6 +23,7 @@ public interface ReviewerApi {
 
   Map<String, Short> votes() throws RestApiException;
   void deleteVote(String label) throws RestApiException;
+  void remove() throws RestApiException;
 
   /**
    * A default implementation which allows source compatibility
@@ -38,5 +39,10 @@ public interface ReviewerApi {
     public void deleteVote(String label) throws RestApiException {
       throw new NotImplementedException();
     }
+
+    @Override
+    public void remove() throws RestApiException {
+      throw new NotImplementedException();
+    }
   }
 }

gerrit-server/src/main/java/com/google/gerrit/server/api/changes/ReviewerApiImpl.java

@@ -16,6 +16,7 @@ package com.google.gerrit.server.api.changes;
 
 import com.google.gerrit.extensions.api.changes.ReviewerApi;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.server.change.DeleteReviewer;
 import com.google.gerrit.server.change.DeleteVote;
 import com.google.gerrit.server.change.ReviewerResource;
 import com.google.gerrit.server.change.VoteResource;
@@ -35,13 +36,16 @@ public class ReviewerApiImpl implements ReviewerApi {
   private final ReviewerResource reviewer;
   private final Votes.List listVotes;
   private final DeleteVote deleteVote;
+  private final DeleteReviewer deleteReviewer;
 
   @Inject
   ReviewerApiImpl(Votes.List listVotes,
       DeleteVote deleteVote,
+      DeleteReviewer deleteReviewer,
       @Assisted ReviewerResource reviewer) {
     this.listVotes = listVotes;
     this.deleteVote = deleteVote;
+    this.deleteReviewer = deleteReviewer;
     this.reviewer = reviewer;
   }
 
@@ -62,4 +66,13 @@ public class ReviewerApiImpl implements ReviewerApi {
       throw new RestApiException("Cannot delete vote", e);
     }
   }
+
+  @Override
+  public void remove() throws RestApiException {
+    try {
+      deleteReviewer.apply(reviewer, null);
+    } catch (UpdateException e) {
+      throw new RestApiException("Cannot remove reviewer", e);
+    }
+  }
 }