Support to retrieve reflog entries by timestamp

Change-Id: I9a865d8543a8e83d4d988ffbda8bf0166b76569a
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>

Documentation/rest-api-projects.txt

@@ -832,6 +832,14 @@ Query the last 25 reflog entries.
   GET /projects/gerrit/branches/master/reflog?n=25 HTTP/1.0
 ----
 
+The reflog can also be filtered by timestamp by specifying the `from`
+and `to` parameters. The timestamp for `from` and `to` must be given as
+UTC in the following format: `yyyyMMdd_HHmm`.
+
+----
+  GET /projects/gerrit/branches/master/reflog?from=20130101_0000&to=20140101_0000=25 HTTP/1.0
+----
+
 [[child-project-endpoints]]
 == Child Project Endpoints
 

gerrit-server/src/main/java/com/google/gerrit/server/CmdLineParserModule.java

@@ -26,6 +26,7 @@ import com.google.gerrit.server.args4j.ObjectIdHandler;
 import com.google.gerrit.server.args4j.PatchSetIdHandler;
 import com.google.gerrit.server.args4j.ProjectControlHandler;
 import com.google.gerrit.server.args4j.SocketAddressHandler;
+import com.google.gerrit.server.args4j.TimestampHandler;
 import com.google.gerrit.server.config.FactoryModule;
 import com.google.gerrit.server.project.ProjectControl;
 import com.google.gerrit.util.cli.CmdLineParser;
@@ -35,6 +36,7 @@ import org.eclipse.jgit.lib.ObjectId;
 import org.kohsuke.args4j.spi.OptionHandler;
 
 import java.net.SocketAddress;
+import java.sql.Timestamp;
 
 public class CmdLineParserModule extends FactoryModule {
   public CmdLineParserModule() {
@@ -53,6 +55,7 @@ public class CmdLineParserModule extends FactoryModule {
     registerOptionHandler(PatchSet.Id.class, PatchSetIdHandler.class);
     registerOptionHandler(ProjectControl.class, ProjectControlHandler.class);
     registerOptionHandler(SocketAddress.class, SocketAddressHandler.class);
+    registerOptionHandler(Timestamp.class, TimestampHandler.class);
   }
 
   private <T> void registerOptionHandler(Class<T> type,

gerrit-server/src/main/java/com/google/gerrit/server/args4j/TimestampHandler.java

@@ -0,0 +1,61 @@
+// Copyright (C) 2014 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.args4j;
+
+import com.google.inject.Inject;
+import com.google.inject.assistedinject.Assisted;
+
+import org.kohsuke.args4j.CmdLineException;
+import org.kohsuke.args4j.CmdLineParser;
+import org.kohsuke.args4j.OptionDef;
+import org.kohsuke.args4j.spi.OptionHandler;
+import org.kohsuke.args4j.spi.Parameters;
+import org.kohsuke.args4j.spi.Setter;
+
+import java.sql.Timestamp;
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.TimeZone;
+
+public class TimestampHandler extends OptionHandler<Timestamp> {
+  public final static String TIMESTAMP_FORMAT = "yyyyMMdd_HHmm";
+
+  @Inject
+  public TimestampHandler(@Assisted CmdLineParser parser,
+      @Assisted OptionDef option, @Assisted Setter<Timestamp> setter) {
+    super(parser, option, setter);
+  }
+
+  @Override
+  public int parseArguments(Parameters params) throws CmdLineException {
+    String timestamp = params.getParameter(0);
+    try {
+      DateFormat fmt = new SimpleDateFormat(TIMESTAMP_FORMAT);
+      fmt.setTimeZone(TimeZone.getTimeZone("UTC"));
+      setter.addValue(new Timestamp(fmt.parse(timestamp).getTime()));
+      return 1;
+    } catch (ParseException e) {
+      throw new CmdLineException(owner,
+          String.format("Invalid timestamp: %s; expected format: %s",
+              timestamp, TIMESTAMP_FORMAT), e);
+    }
+  }
+
+  @Override
+  public String getDefaultMetaVariable() {
+    return "TIMESTAMP";
+  }
+}

gerrit-server/src/main/java/com/google/gerrit/server/project/GetReflog.java

@@ -20,6 +20,7 @@ import com.google.gerrit.extensions.common.GitPerson;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.RestReadView;
+import com.google.gerrit.server.args4j.TimestampHandler;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.inject.Inject;
 
@@ -32,6 +33,7 @@ import org.kohsuke.args4j.Option;
 
 import java.io.IOException;
 import java.sql.Timestamp;
+import java.util.ArrayList;
 import java.util.List;
 
 public class GetReflog implements RestReadView<BranchResource> {
@@ -44,7 +46,25 @@ public class GetReflog implements RestReadView<BranchResource> {
     return this;
   }
 
+  @Option(name = "--from", metaVar = "TIMESTAMP",
+      usage = "timestamp from which the reflog entries should be listed (UTC, format: "
+          + TimestampHandler.TIMESTAMP_FORMAT + ")")
+  public GetReflog setFrom(Timestamp from) {
+    this.from = from;
+    return this;
+  }
+
+  @Option(name = "--to", metaVar = "TIMESTAMP",
+      usage = "timestamp until which the reflog entries should be listed (UTC, format: "
+          + TimestampHandler.TIMESTAMP_FORMAT + ")")
+  public GetReflog setTo(Timestamp to) {
+    this.to = to;
+    return this;
+  }
+
   private int limit;
+  private Timestamp from;
+  private Timestamp to;
 
   @Inject
   public GetReflog(GitRepositoryManager repoManager) {
@@ -64,8 +84,25 @@ public class GetReflog implements RestReadView<BranchResource> {
       if (r == null) {
         throw new ResourceNotFoundException(rsrc.getRef());
       }
-      List<ReflogEntry> entries =
+      List<ReflogEntry> entries;
+      if (from == null && to == null) {
+        entries =
             limit > 0 ? r.getReverseEntries(limit) : r.getReverseEntries();
+      } else {
+        entries = limit > 0
+            ? new ArrayList<ReflogEntry>(limit)
+            : new ArrayList<ReflogEntry>();
+        for (ReflogEntry e : r.getReverseEntries()) {
+          Timestamp timestamp = new Timestamp(e.getWho().getWhen().getTime());
+          if ((from == null || from.before(timestamp)) &&
+              (to == null || to.after(timestamp))) {
+            entries.add(e);
+          }
+          if (limit > 0 && entries.size() >= limit) {
+            break;
+          }
+        }
+      }
       return Lists.transform(entries, new Function<ReflogEntry, ReflogEntryInfo>() {
         @Override
         public ReflogEntryInfo apply(ReflogEntry e) {