implement cat command for git

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitCatCommand.java

@@ -0,0 +1,196 @@
+/**
+ * Copyright (c) 2010, Sebastian Sdorra All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer. 2. Redistributions in
+ * binary form must reproduce the above copyright notice, this list of
+ * conditions and the following disclaimer in the documentation and/or other
+ * materials provided with the distribution. 3. Neither the name of SCM-Manager;
+ * nor the names of its contributors may be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://bitbucket.org/sdorra/scm-manager
+ *
+ */
+
+
+
+package sonia.scm.repository.spi;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectLoader;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevTree;
+import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.treewalk.TreeWalk;
+import org.eclipse.jgit.treewalk.filter.PathFilter;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import sonia.scm.repository.GitUtil;
+import sonia.scm.repository.PathNotFoundException;
+import sonia.scm.repository.RepositoryException;
+import sonia.scm.util.Util;
+
+//~--- JDK imports ------------------------------------------------------------
+
+import java.io.File;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class GitCatCommand extends AbstractGitCommand implements CatCommand
+{
+
+  /**
+   * the logger for GitCatCommand
+   */
+  private static final Logger logger =
+    LoggerFactory.getLogger(GitCatCommand.class);
+
+  //~--- constructors ---------------------------------------------------------
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param repository
+   * @param repositoryDirectory
+   */
+  public GitCatCommand(sonia.scm.repository.Repository repository,
+                       File repositoryDirectory)
+  {
+    super(repository, repositoryDirectory);
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @param request
+   * @param output
+   */
+  @Override
+  public void getCatResult(CatCommandRequest request, OutputStream output)
+  {
+    org.eclipse.jgit.lib.Repository repo = null;
+
+    try
+    {
+      repo = open();
+
+      ObjectId revId = GitUtil.getRevisionId(repo, request.getRevision());
+
+      getContent(repo, revId, request.getPath(), output);
+    }
+    catch (Exception ex)
+    {
+      //TODO throw
+      logger.error("could not fetch content", ex);
+    }
+    finally
+    {
+      GitUtil.close(repo);
+    }
+  }
+
+  /**
+   * Method description
+   *
+   *
+   *
+   * @param repo
+   * @param revId
+   * @param path
+   * @param output
+   *
+   *
+   * @throws IOException
+   * @throws RepositoryException
+   */
+  public void getContent(org.eclipse.jgit.lib.Repository repo, ObjectId revId,
+                         String path, OutputStream output)
+          throws IOException, RepositoryException
+  {
+    TreeWalk treeWalk = null;
+    RevWalk revWalk = null;
+
+    try
+    {
+      treeWalk = new TreeWalk(repo);
+      treeWalk.setRecursive(Util.nonNull(path).contains("/"));
+
+      if (logger.isDebugEnabled())
+      {
+        logger.debug("load content for {} at {}", path, revId.name());
+      }
+
+      revWalk = new RevWalk(repo);
+
+      RevCommit entry = revWalk.parseCommit(revId);
+      RevTree revTree = entry.getTree();
+
+      if (revTree != null)
+      {
+        treeWalk.addTree(revTree);
+      }
+      else
+      {
+        logger.error("could not find tree for {}", revId.name());
+      }
+
+      treeWalk.setFilter(PathFilter.create(path));
+
+      if (treeWalk.next())
+      {
+
+        // Path exists
+        if (treeWalk.getFileMode(0).getObjectType() == Constants.OBJ_BLOB)
+        {
+          ObjectId blobId = treeWalk.getObjectId(0);
+          ObjectLoader loader = repo.open(blobId);
+
+          loader.copyTo(output);
+        }
+        else
+        {
+
+          // Not a blob, its something else (tree, gitlink)
+          throw new PathNotFoundException(path);
+        }
+      }
+      else
+      {
+        throw new PathNotFoundException(path);
+      }
+    }
+    finally
+    {
+      GitUtil.release(revWalk);
+      GitUtil.release(treeWalk);
+    }
+  }
+}

scm-plugins/scm-git-plugin/src/main/java/sonia/scm/repository/spi/GitRepositoryServiceProvider.java

@@ -53,7 +53,8 @@ public class GitRepositoryServiceProvider extends RepositoryServiceProvider
 {
 
   /** Field description */
-  private static final Set<Command> COMMANDS = ImmutableSet.of(Command.LOG);
+  private static final Set<Command> COMMANDS = ImmutableSet.of(Command.CAT,
+                                                 Command.LOG);
 
   //~--- constructors ---------------------------------------------------------
 
@@ -73,6 +74,18 @@ public class GitRepositoryServiceProvider extends RepositoryServiceProvider
 
   //~--- get methods ----------------------------------------------------------
 
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  @Override
+  public CatCommand getCatCommand()
+  {
+    return new GitCatCommand(repository, repositoryDirectory);
+  }
+
   /**
    * Method description
    *