1 files changed, 101 insertions, 0 deletions
diff --git a/java/com/google/gerrit/server/submit/GitModules.java b/java/com/google/gerrit/server/submit/GitModules.java
new file mode 100644
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+++ b/java/com/google/gerrit/server/submit/GitModules.java
@@ -0,0 +1,101 @@
+// Copyright (C) 2016 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.submit;
+
+import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.reviewdb.client.Branch;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.client.SubmoduleSubscription;
+import com.google.gerrit.server.config.CanonicalWebUrl;
+import com.google.gerrit.server.project.NoSuchProjectException;
+import com.google.gerrit.server.submit.MergeOpRepoManager.OpenRepo;
+import com.google.gerrit.server.util.git.SubmoduleSectionParser;
+import com.google.inject.Inject;
+import com.google.inject.assistedinject.Assisted;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Set;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+import org.eclipse.jgit.lib.BlobBasedConfig;
+import org.eclipse.jgit.lib.FileMode;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.treewalk.TreeWalk;
+
+/**
+ * Loads the .gitmodules file of the specified project/branch. It can be queried which submodules
+ * this branch is subscribed to.
+ */
+public class GitModules {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  public interface Factory {
+    GitModules create(Branch.NameKey project, MergeOpRepoManager m);
+  }
+
+  private static final String GIT_MODULES = ".gitmodules";
+
+  private Set<SubmoduleSubscription> subscriptions;
+
+  @Inject
+  GitModules(
+      @CanonicalWebUrl @Nullable String canonicalWebUrl,
+      @Assisted Branch.NameKey branch,
+      @Assisted MergeOpRepoManager orm)
+      throws IOException {
+    Project.NameKey project = branch.getParentKey();
+    logger.atFine().log("Loading .gitmodules of %s for project %s", branch, project);
+    try {
+      OpenRepo or = orm.getRepo(project);
+      ObjectId id = or.repo.resolve(branch.get());
+      if (id == null) {
+        throw new IOException("Cannot open branch " + branch.get());
+      }
+      RevCommit commit = or.rw.parseCommit(id);
+
+      try (TreeWalk tw = TreeWalk.forPath(or.repo, GIT_MODULES, commit.getTree())) {
+        if (tw == null || (tw.getRawMode(0) & FileMode.TYPE_MASK) != FileMode.TYPE_FILE) {
+          subscriptions = Collections.emptySet();
+          logger.atFine().log("The .gitmodules file doesn't exist in %s", branch);
+          return;
+        }
+      }
+      BlobBasedConfig config;
+      try {
+        config = new BlobBasedConfig(null, or.repo, commit, GIT_MODULES);
+      } catch (ConfigInvalidException e) {
+        throw new IOException(
+            "Could not read .gitmodules of super project: " + branch.getParentKey(), e);
+      }
+      subscriptions =
+          new SubmoduleSectionParser(config, canonicalWebUrl, branch).parseAllSections();
+    } catch (NoSuchProjectException e) {
+      throw new IOException(e);
+    }
+  }
+
+  Collection<SubmoduleSubscription> subscribedTo(Branch.NameKey src) {
+    Collection<SubmoduleSubscription> ret = new ArrayList<>();
+    for (SubmoduleSubscription s : subscriptions) {
+      if (s.getSubmodule().equals(src)) {
+        ret.add(s);
+      }
+    }
+    return ret;
+  }
+}