Support triggering GC for one project via REST

The Git garbage collection for one project can now be triggered by
POST on '/projects/*/gc'.

Change-Id: I6d45f33196f3f356648c817d9a2d8465de49bb5c
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>

Documentation/rest-api-projects.txt

@@ -408,6 +408,45 @@ link:#repository-statistics-info[RepositoryStatisticsInfo] entity.
   }
 ----
 
+[[run-gc]]
+Run GC
+~~~~~~
+[verse]
+'POST /projects/link:#project-name[\{project-name\}]/gc'
+
+Run the Git garbage collection for the repository of a project.
+
+.Request
+----
+  POST /projects/plugins%2Freplication/gc HTTP/1.0
+----
+
+The response is the streamed output of the garbage collection.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: text/plain;charset=UTF-8
+
+  collecting garbage for "plugins/replication":
+  Pack refs:              100% (21/21)
+  Counting objects:       20
+  Finding sources:        100% (20/20)
+  Getting sizes:          100% (13/13)
+  Compressing objects:     83% (5/6)
+  Writing objects:        100% (20/20)
+  Selecting commits:      100% (7/7)
+  Building bitmaps:       100% (7/7)
+  Finding sources:        100% (41/41)
+  Getting sizes:          100% (25/25)
+  Compressing objects:     52% (12/23)
+  Writing objects:        100% (41/41)
+  Prune loose objects also found in pack files: 100% (36/36)
+  Prune loose, unreferenced objects: 100% (36/36)
+  done.
+----
+
 [[dashboard-endpoints]]
 Dashboard Endpoints
 -------------------

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/GcAssert.java

@@ -0,0 +1,70 @@
+// Copyright (C) 2013 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.acceptance;
+
+import static org.junit.Assert.assertTrue;
+
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.server.git.GitRepositoryManager;
+import com.google.inject.Inject;
+
+import org.eclipse.jgit.errors.RepositoryNotFoundException;
+import org.eclipse.jgit.lib.Repository;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.IOException;
+
+public class GcAssert {
+
+  private final GitRepositoryManager repoManager;
+
+  @Inject
+  public GcAssert(GitRepositoryManager repoManager) {
+    this.repoManager = repoManager;
+  }
+
+  public void assertHasPackFile(Project.NameKey... projects)
+      throws RepositoryNotFoundException, IOException {
+    for (Project.NameKey p : projects) {
+      assertTrue("Project " + p.get() + " has no pack files.",
+          getPackFiles(p).length > 0);
+    }
+  }
+
+  public void assertHasNoPackFile(Project.NameKey... projects)
+      throws RepositoryNotFoundException, IOException {
+    for (Project.NameKey p : projects) {
+      assertTrue("Project " + p.get() + " has pack files.",
+          getPackFiles(p).length == 0);
+    }
+  }
+
+  private String[] getPackFiles(Project.NameKey p)
+      throws RepositoryNotFoundException, IOException {
+    Repository repo = repoManager.openRepository(p);
+    try {
+      File packDir = new File(repo.getDirectory(), "objects/pack");
+      return packDir.list(new FilenameFilter() {
+        @Override
+        public boolean accept(File dir, String name) {
+          return name.endsWith(".pack");
+        }
+      });
+    } finally {
+      repo.close();
+    }
+  }
+}

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/RestSession.java

@@ -56,6 +56,10 @@ public class RestSession {
     return new RestResponse(getClient().execute(put));
   }
 
+  public RestResponse post(String endPoint) throws IOException {
+    return post(endPoint, null);
+  }
+
   public RestResponse post(String endPoint, Object content) throws IOException {
     HttpPost post = new HttpPost("http://localhost:8080/a" + endPoint);
     if (content != null) {

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/rest/project/GarbageCollectionIT.java

@@ -0,0 +1,102 @@
+// Copyright (C) 2013 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.acceptance.rest.project;
+
+import static com.google.gerrit.acceptance.git.GitUtil.createProject;
+import static org.junit.Assert.assertEquals;
+
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.AccountCreator;
+import com.google.gerrit.acceptance.GcAssert;
+import com.google.gerrit.acceptance.RestResponse;
+import com.google.gerrit.acceptance.RestSession;
+import com.google.gerrit.acceptance.SshSession;
+import com.google.gerrit.acceptance.TestAccount;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.server.config.AllProjectsName;
+import com.google.gerrit.server.git.GarbageCollectionQueue;
+import com.google.gwtorm.server.OrmException;
+import com.google.inject.Inject;
+
+import com.jcraft.jsch.JSchException;
+
+import org.apache.http.HttpStatus;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+
+public class GarbageCollectionIT extends AbstractDaemonTest {
+
+  @Inject
+  private AccountCreator accounts;
+
+  @Inject
+  private AllProjectsName allProjects;
+
+  @Inject
+  private GarbageCollectionQueue gcQueue;
+
+  @Inject
+  private GcAssert gcAssert;
+
+  private TestAccount admin;
+  private RestSession session;
+  private Project.NameKey project1;
+  private Project.NameKey project2;
+
+  @Before
+  public void setUp() throws Exception {
+    admin =
+        accounts.create("admin", "admin@example.com", "Administrator",
+            "Administrators");
+
+    SshSession sshSession = new SshSession(admin);
+
+    project1 = new Project.NameKey("p1");
+    createProject(sshSession, project1.get());
+
+    project2 = new Project.NameKey("p2");
+    createProject(sshSession, project2.get());
+
+    session = new RestSession(admin);
+  }
+
+  @Test
+  public void testGcNonExistingProject_NotFound() throws IOException {
+    assertEquals(HttpStatus.SC_NOT_FOUND, POST("/projects/non-existing/gc"));
+  }
+
+  @Test
+  public void testGcNotAllowed_Forbidden() throws IOException, OrmException, JSchException {
+    assertEquals(HttpStatus.SC_FORBIDDEN,
+        new RestSession(accounts.create("user", "user@example.com", "User"))
+            .post("/projects/" + allProjects.get() + "/gc").getStatusCode());
+  }
+
+  @Test
+  public void testGcOneProject() throws JSchException, IOException {
+
+    assertEquals(HttpStatus.SC_OK, POST("/projects/" + allProjects.get() + "/gc"));
+    gcAssert.assertHasPackFile(allProjects);
+    gcAssert.assertHasNoPackFile(project1, project2);
+  }
+
+  private int POST(String endPoint) throws IOException {
+    RestResponse r = session.post(endPoint);
+    r.consume();
+    return r.getStatusCode();
+  }
+}

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/ssh/GarbageCollectionIT.java

@@ -21,6 +21,7 @@ import static org.junit.Assert.assertTrue;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.AccountCreator;
+import com.google.gerrit.acceptance.GcAssert;
 import com.google.gerrit.acceptance.SshSession;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.common.data.GarbageCollectionResult;
@@ -28,19 +29,14 @@ import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.server.config.AllProjectsName;
 import com.google.gerrit.server.git.GarbageCollection;
 import com.google.gerrit.server.git.GarbageCollectionQueue;
-import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 
 import com.jcraft.jsch.JSchException;
 
-import org.eclipse.jgit.errors.RepositoryNotFoundException;
-import org.eclipse.jgit.lib.Repository;
 import org.junit.Before;
 import org.junit.Test;
 
-import java.io.File;
-import java.io.FilenameFilter;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Locale;
@@ -50,9 +46,6 @@ public class GarbageCollectionIT extends AbstractDaemonTest {
   @Inject
   private AccountCreator accounts;
 
-  @Inject
-  private GitRepositoryManager repoManager;
-
   @Inject
   private AllProjectsName allProjects;
 
@@ -62,6 +55,9 @@ public class GarbageCollectionIT extends AbstractDaemonTest {
   @Inject
   private GarbageCollectionQueue gcQueue;
 
+  @Inject
+  private GcAssert gcAssert;
+
   private TestAccount admin;
   private SshSession sshSession;
   private Project.NameKey project1;
@@ -93,8 +89,8 @@ public class GarbageCollectionIT extends AbstractDaemonTest {
             + project2.get() + "\"");
     assertFalse(sshSession.hasError());
     assertNoError(response);
-    assertHasPackFile(project1, project2);
+    gcAssert.assertHasPackFile(project1, project2);
-    assertHasNoPackFile(allProjects, project3);
+    gcAssert.assertHasNoPackFile(allProjects, project3);
   }
 
   @Test
@@ -102,7 +98,7 @@ public class GarbageCollectionIT extends AbstractDaemonTest {
     String response = sshSession.exec("gerrit gc --all");
     assertFalse(sshSession.hasError());
     assertNoError(response);
-    assertHasPackFile(allProjects, project1, project2, project3);
+    gcAssert.assertHasPackFile(allProjects, project1, project2, project3);
   }
 
   @Test
@@ -132,36 +128,4 @@ public class GarbageCollectionIT extends AbstractDaemonTest {
   private void assertNoError(String response) {
     assertFalse(response, response.toLowerCase(Locale.US).contains("error"));
   }
-
-  private void assertHasPackFile(Project.NameKey... projects)
-      throws RepositoryNotFoundException, IOException {
-    for (Project.NameKey p : projects) {
-      assertTrue("Project " + p.get() + "has no pack files.",
-          getPackFiles(p).length > 0);
-    }
-  }
-
-  private void assertHasNoPackFile(Project.NameKey... projects)
-      throws RepositoryNotFoundException, IOException {
-    for (Project.NameKey p : projects) {
-      assertTrue("Project " + p.get() + "has pack files.",
-          getPackFiles(p).length == 0);
-    }
-  }
-
-  private String[] getPackFiles(Project.NameKey p)
-      throws RepositoryNotFoundException, IOException {
-    Repository repo = repoManager.openRepository(p);
-    try {
-      File packDir = new File(repo.getDirectory(), "objects/pack");
-      return packDir.list(new FilenameFilter() {
-        @Override
-        public boolean accept(File dir, String name) {
-          return name.endsWith(".pack");
-        }
-      });
-    } finally {
-      repo.close();
-    }
-  }
 }

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/restapi/StreamingResponse.java

@@ -0,0 +1,23 @@
+// Copyright (C) 2013 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.extensions.restapi;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+public interface StreamingResponse {
+  public String getContentType();
+  public void stream(OutputStream out) throws IOException;
+}

gerrit-httpd/src/main/java/com/google/gerrit/httpd/restapi/RestApiServlet.java

@@ -61,6 +61,7 @@ import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.RestReadView;
 import com.google.gerrit.extensions.restapi.RestResource;
 import com.google.gerrit.extensions.restapi.RestView;
+import com.google.gerrit.extensions.restapi.StreamingResponse;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.httpd.WebSession;
@@ -301,7 +302,11 @@ public class RestApiServlet extends HttpServlet {
       }
       res.setStatus(status);
 
-      if (result != Response.none()) {
+      if (result instanceof StreamingResponse) {
+        StreamingResponse r = (StreamingResponse) result;
+        res.setContentType(r.getContentType());
+        r.stream(res.getOutputStream());
+      } else if (result != Response.none()) {
         result = Response.unwrap(result);
         if (result instanceof BinaryResult) {
           replyBinaryResult(req, res, (BinaryResult) result);

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

@@ -0,0 +1,93 @@
+// Copyright (C) 2013 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.project;
+
+import com.google.common.base.Charsets;
+import com.google.gerrit.common.data.GarbageCollectionResult;
+import com.google.gerrit.common.data.GlobalCapability;
+import com.google.gerrit.extensions.annotations.RequiresCapability;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.extensions.restapi.StreamingResponse;
+import com.google.gerrit.server.git.GarbageCollection;
+import com.google.gerrit.server.project.GarbageCollect.Input;
+import com.google.inject.Inject;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintWriter;
+import java.util.Collections;
+
+@RequiresCapability(GlobalCapability.RUN_GC)
+public class GarbageCollect implements RestModifyView<ProjectResource, Input> {
+  public static class Input {
+  }
+
+  private GarbageCollection.Factory garbageCollectionFactory;
+
+  @Inject
+  GarbageCollect(GarbageCollection.Factory garbageCollectionFactory) {
+    this.garbageCollectionFactory = garbageCollectionFactory;
+  }
+
+  @Override
+  public StreamingResponse apply(final ProjectResource rsrc, Input input) {
+    return new StreamingResponse() {
+      @Override
+      public String getContentType() {
+        return "text/plain;charset=UTF-8";
+      }
+
+      @Override
+      public void stream(OutputStream out) throws IOException {
+        PrintWriter writer = new PrintWriter(
+            new OutputStreamWriter(out, Charsets.UTF_8)) {
+          @Override
+          public void println() {
+            write('\n');
+          }
+        };
+        try {
+          GarbageCollectionResult result = garbageCollectionFactory.create().run(
+              Collections.singletonList(rsrc.getNameKey()), writer);
+          if (result.hasErrors()) {
+            for (GarbageCollectionResult.Error e : result.getErrors()) {
+              String msg;
+              switch (e.getType()) {
+                case REPOSITORY_NOT_FOUND:
+                  msg = "error: project \"" + e.getProjectName() + "\" not found";
+                  break;
+                case GC_ALREADY_SCHEDULED:
+                  msg = "error: garbage collection for project \""
+                      + e.getProjectName() + "\" was already scheduled";
+                  break;
+                case GC_FAILED:
+                  msg = "error: garbage collection for project \"" + e.getProjectName()
+                      + "\" failed";
+                  break;
+                default:
+                  msg = "error: garbage collection for project \"" + e.getProjectName()
+                      + "\" failed: " + e.getType();
+              }
+              writer.println(msg);
+            }
+          }
+        } finally {
+          writer.flush();
+        }
+      }
+    };
+  }
+}

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

@@ -44,6 +44,7 @@ public class Module extends RestApiModule {
     put(PROJECT_KIND, "HEAD").to(SetHead.class);
 
     get(PROJECT_KIND, "statistics.git").to(GetStatistics.class);
+    post(PROJECT_KIND, "gc").to(GarbageCollect.class);
 
     child(PROJECT_KIND, "dashboards").to(DashboardsCollection.class);
     get(DASHBOARD_KIND).to(GetDashboard.class);