gerrit-server/src/main/java/com/google/gerrit/server/project/CreateBranch.java - gerrit - Git at Google

 // 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.collect.Iterables;
 import com.google.gerrit.common.ChangeHooks;
 import com.google.gerrit.common.errors.InvalidRevisionException;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.DefaultInput;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.reviewdb.client.Branch;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.client.RefNames;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.project.CreateBranch.Input;
 import com.google.gerrit.server.project.ListBranches.BranchInfo;
 import com.google.gerrit.server.util.MagicBranch;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.assistedinject.Assisted;

 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.errors.RevisionSyntaxException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.RefDatabase;
 import org.eclipse.jgit.lib.RefUpdate;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.ObjectWalk;
 import org.eclipse.jgit.revwalk.RevObject;
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 import java.io.IOException;
 import java.util.Collections;

 public class CreateBranch implements RestModifyView<ProjectResource, Input> {
   private static final Logger log = LoggerFactory.getLogger(CreateBranch.class);

   public static class Input {
     public String ref;

     @DefaultInput
     public String revision;
   }

   public static interface Factory {
     CreateBranch create(String ref);
   }

   private final Provider<IdentifiedUser>  identifiedUser;
   private final GitRepositoryManager repoManager;
   private final Provider<ReviewDb> db;
   private final GitReferenceUpdated referenceUpdated;
   private final ChangeHooks hooks;
   private String ref;

   @Inject
   CreateBranch(Provider<IdentifiedUser> identifiedUser,
       GitRepositoryManager repoManager,
       Provider<ReviewDb> db,
       GitReferenceUpdated referenceUpdated, ChangeHooks hooks,
       @Assisted String ref) {
     this.identifiedUser = identifiedUser;
     this.repoManager = repoManager;
     this.db = db;
     this.referenceUpdated = referenceUpdated;
     this.hooks = hooks;
     this.ref = ref;
   }

   @Override
   public BranchInfo apply(ProjectResource rsrc, Input input)
       throws BadRequestException, AuthException, ResourceConflictException,
       IOException {
     if (input == null) {
       input = new Input();
     }
     if (input.ref != null && !ref.equals(input.ref)) {
       throw new BadRequestException("ref must match URL");
     }
     if (input.revision == null) {
       input.revision = Constants.HEAD;
     }
     while (ref.startsWith("/")) {
       ref = ref.substring(1);
     }
     if (!ref.startsWith(Constants.R_REFS)) {
       ref = Constants.R_HEADS + ref;
     }
     if (!Repository.isValidRefName(ref)) {
       throw new BadRequestException("invalid branch name \"" + ref + "\"");
     }
     if (MagicBranch.isMagicBranch(ref)) {
       throw new BadRequestException("not allowed to create branches under \""
           + MagicBranch.getMagicRefNamePrefix(ref) + "\"");
     }

     final Branch.NameKey name = new Branch.NameKey(rsrc.getNameKey(), ref);
     final RefControl refControl = rsrc.getControl().controlForRef(name);
     final Repository repo = repoManager.openRepository(rsrc.getNameKey());
     try {
       final ObjectId revid = parseBaseRevision(repo, rsrc.getNameKey(), input.revision);
       final RevWalk rw = verifyConnected(repo, revid);
       RevObject object = rw.parseAny(revid);

       if (ref.startsWith(Constants.R_HEADS)) {
         // Ensure that what we start the branch from is a commit. If we
         // were given a tag, deference to the commit instead.
         //
         try {
           object = rw.parseCommit(object);
         } catch (IncorrectObjectTypeException notCommit) {
           throw new BadRequestException("\"" + input.revision + "\" not a commit");
         }
       }

       rw.reset();
       if (!refControl.canCreate(db.get(), rw, object)) {
         throw new AuthException("Cannot create \"" + ref + "\"");
       }

       try {
         final RefUpdate u = repo.updateRef(ref);
         u.setExpectedOldObjectId(ObjectId.zeroId());
         u.setNewObjectId(object.copy());
         u.setRefLogIdent(identifiedUser.get().newRefLogIdent());
         u.setRefLogMessage("created via REST from " + input.revision, false);
         final RefUpdate.Result result = u.update(rw);
         switch (result) {
           case FAST_FORWARD:
           case NEW:
           case NO_CHANGE:
             referenceUpdated.fire(name.getParentKey(), u);
             hooks.doRefUpdatedHook(name, u, identifiedUser.get().getAccount());
             break;
           case LOCK_FAILURE:
             if (repo.getRef(ref) != null) {
               throw new ResourceConflictException("branch \"" + ref
                   + "\" already exists");
             }
             String refPrefix = getRefPrefix(ref);
             while (!Constants.R_HEADS.equals(refPrefix)) {
               if (repo.getRef(refPrefix) != null) {
                 throw new ResourceConflictException("Cannot create branch \""
                     + ref + "\" since it conflicts with branch \"" + refPrefix
                     + "\".");
               }
               refPrefix = getRefPrefix(refPrefix);
             }
             //$FALL-THROUGH$
           default: {
             throw new IOException(result.name());
           }
         }

         return new BranchInfo(ref, revid.getName(), refControl.canDelete());
       } catch (IOException err) {
         log.error("Cannot create branch \"" + name + "\"", err);
         throw err;
       }
     } catch (InvalidRevisionException e) {
       throw new BadRequestException("invalid revision \"" + input.revision + "\"");
     } finally {
       repo.close();
     }
   }

   private static String getRefPrefix(final String refName) {
     final int i = refName.lastIndexOf('/');
     if (i > Constants.R_HEADS.length() - 1) {
       return refName.substring(0, i);
     }
     return Constants.R_HEADS;
   }

   private ObjectId parseBaseRevision(Repository repo,
       Project.NameKey projectName, String baseRevision)
       throws InvalidRevisionException {
     try {
       final ObjectId revid = repo.resolve(baseRevision);
       if (revid == null) {
         throw new InvalidRevisionException();
       }
       return revid;
     } catch (IOException err) {
       log.error("Cannot resolve \"" + baseRevision + "\" in project \""
           + projectName.get() + "\"", err);
       throw new InvalidRevisionException();
     } catch (RevisionSyntaxException err) {
       log.error("Invalid revision syntax \"" + baseRevision + "\"", err);
       throw new InvalidRevisionException();
     }
   }

   private RevWalk verifyConnected(final Repository repo, final ObjectId revid)
       throws InvalidRevisionException {
     try {
       final ObjectWalk rw = new ObjectWalk(repo);
       try {
         rw.markStart(rw.parseCommit(revid));
       } catch (IncorrectObjectTypeException err) {
         throw new InvalidRevisionException();
       }
       RefDatabase refDb = repo.getRefDatabase();
       Iterable<Ref> refs = Iterables.concat(
           refDb.getRefs(Constants.R_HEADS).values(),
           refDb.getRefs(Constants.R_TAGS).values());
       Ref rc = refDb.getRef(RefNames.REFS_CONFIG);
       if (rc != null) {
         refs = Iterables.concat(refs, Collections.singleton(rc));
       }
       for (Ref r : refs) {
         try {
           rw.markUninteresting(rw.parseAny(r.getObjectId()));
         } catch (MissingObjectException err) {
           continue;
         }
       }
       rw.checkConnectivity();
       return rw;
     } catch (IncorrectObjectTypeException err) {
       throw new InvalidRevisionException();
     } catch (MissingObjectException err) {
       throw new InvalidRevisionException();
     } catch (IOException err) {
       log.error("Repository \"" + repo.getDirectory()
           + "\" may be corrupt; suggest running git fsck", err);
       throw new InvalidRevisionException();
     }
   }
 }
	// 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.collect.Iterables;
	import com.google.gerrit.common.ChangeHooks;
	import com.google.gerrit.common.errors.InvalidRevisionException;
	import com.google.gerrit.extensions.restapi.AuthException;
	import com.google.gerrit.extensions.restapi.BadRequestException;
	import com.google.gerrit.extensions.restapi.DefaultInput;
	import com.google.gerrit.extensions.restapi.ResourceConflictException;
	import com.google.gerrit.extensions.restapi.RestModifyView;
	import com.google.gerrit.reviewdb.client.Branch;
	import com.google.gerrit.reviewdb.client.Project;
	import com.google.gerrit.reviewdb.client.RefNames;
	import com.google.gerrit.reviewdb.server.ReviewDb;
	import com.google.gerrit.server.IdentifiedUser;
	import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
	import com.google.gerrit.server.git.GitRepositoryManager;
	import com.google.gerrit.server.project.CreateBranch.Input;
	import com.google.gerrit.server.project.ListBranches.BranchInfo;
	import com.google.gerrit.server.util.MagicBranch;
	import com.google.inject.Inject;
	import com.google.inject.Provider;
	import com.google.inject.assistedinject.Assisted;

	import org.eclipse.jgit.errors.IncorrectObjectTypeException;
	import org.eclipse.jgit.errors.MissingObjectException;
	import org.eclipse.jgit.errors.RevisionSyntaxException;
	import org.eclipse.jgit.lib.Constants;
	import org.eclipse.jgit.lib.ObjectId;
	import org.eclipse.jgit.lib.Ref;
	import org.eclipse.jgit.lib.RefDatabase;
	import org.eclipse.jgit.lib.RefUpdate;
	import org.eclipse.jgit.lib.Repository;
	import org.eclipse.jgit.revwalk.ObjectWalk;
	import org.eclipse.jgit.revwalk.RevObject;
	import org.eclipse.jgit.revwalk.RevWalk;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	import java.io.IOException;
	import java.util.Collections;

	public class CreateBranch implements RestModifyView<ProjectResource, Input> {
	private static final Logger log = LoggerFactory.getLogger(CreateBranch.class);

	public static class Input {
	public String ref;

	@DefaultInput
	public String revision;
	}

	public static interface Factory {
	CreateBranch create(String ref);
	}

	private final Provider<IdentifiedUser> identifiedUser;
	private final GitRepositoryManager repoManager;
	private final Provider<ReviewDb> db;
	private final GitReferenceUpdated referenceUpdated;
	private final ChangeHooks hooks;
	private String ref;

	@Inject
	CreateBranch(Provider<IdentifiedUser> identifiedUser,
	GitRepositoryManager repoManager,
	Provider<ReviewDb> db,
	GitReferenceUpdated referenceUpdated, ChangeHooks hooks,
	@Assisted String ref) {
	this.identifiedUser = identifiedUser;
	this.repoManager = repoManager;
	this.db = db;
	this.referenceUpdated = referenceUpdated;
	this.hooks = hooks;
	this.ref = ref;
	}

	@Override
	public BranchInfo apply(ProjectResource rsrc, Input input)
	throws BadRequestException, AuthException, ResourceConflictException,
	IOException {
	if (input == null) {
	input = new Input();
	}
	if (input.ref != null && !ref.equals(input.ref)) {
	throw new BadRequestException("ref must match URL");
	}
	if (input.revision == null) {
	input.revision = Constants.HEAD;
	}
	while (ref.startsWith("/")) {
	ref = ref.substring(1);
	}
	if (!ref.startsWith(Constants.R_REFS)) {
	ref = Constants.R_HEADS + ref;
	}
	if (!Repository.isValidRefName(ref)) {
	throw new BadRequestException("invalid branch name \"" + ref + "\"");
	}
	if (MagicBranch.isMagicBranch(ref)) {
	throw new BadRequestException("not allowed to create branches under \""
	+ MagicBranch.getMagicRefNamePrefix(ref) + "\"");
	}

	final Branch.NameKey name = new Branch.NameKey(rsrc.getNameKey(), ref);
	final RefControl refControl = rsrc.getControl().controlForRef(name);
	final Repository repo = repoManager.openRepository(rsrc.getNameKey());
	try {
	final ObjectId revid = parseBaseRevision(repo, rsrc.getNameKey(), input.revision);
	final RevWalk rw = verifyConnected(repo, revid);
	RevObject object = rw.parseAny(revid);

	if (ref.startsWith(Constants.R_HEADS)) {
	// Ensure that what we start the branch from is a commit. If we
	// were given a tag, deference to the commit instead.
	//
	try {
	object = rw.parseCommit(object);
	} catch (IncorrectObjectTypeException notCommit) {
	throw new BadRequestException("\"" + input.revision + "\" not a commit");
	}
	}

	rw.reset();
	if (!refControl.canCreate(db.get(), rw, object)) {
	throw new AuthException("Cannot create \"" + ref + "\"");
	}

	try {
	final RefUpdate u = repo.updateRef(ref);
	u.setExpectedOldObjectId(ObjectId.zeroId());
	u.setNewObjectId(object.copy());
	u.setRefLogIdent(identifiedUser.get().newRefLogIdent());
	u.setRefLogMessage("created via REST from " + input.revision, false);
	final RefUpdate.Result result = u.update(rw);
	switch (result) {
	case FAST_FORWARD:
	case NEW:
	case NO_CHANGE:
	referenceUpdated.fire(name.getParentKey(), u);
	hooks.doRefUpdatedHook(name, u, identifiedUser.get().getAccount());
	break;
	case LOCK_FAILURE:
	if (repo.getRef(ref) != null) {
	throw new ResourceConflictException("branch \"" + ref
	+ "\" already exists");
	}
	String refPrefix = getRefPrefix(ref);
	while (!Constants.R_HEADS.equals(refPrefix)) {
	if (repo.getRef(refPrefix) != null) {
	throw new ResourceConflictException("Cannot create branch \""
	+ ref + "\" since it conflicts with branch \"" + refPrefix
	+ "\".");
	}
	refPrefix = getRefPrefix(refPrefix);
	}
	//$FALL-THROUGH$
	default: {
	throw new IOException(result.name());
	}
	}

	return new BranchInfo(ref, revid.getName(), refControl.canDelete());
	} catch (IOException err) {
	log.error("Cannot create branch \"" + name + "\"", err);
	throw err;
	}
	} catch (InvalidRevisionException e) {
	throw new BadRequestException("invalid revision \"" + input.revision + "\"");
	} finally {
	repo.close();
	}
	}

	private static String getRefPrefix(final String refName) {
	final int i = refName.lastIndexOf('/');
	if (i > Constants.R_HEADS.length() - 1) {
	return refName.substring(0, i);
	}
	return Constants.R_HEADS;
	}

	private ObjectId parseBaseRevision(Repository repo,
	Project.NameKey projectName, String baseRevision)
	throws InvalidRevisionException {
	try {
	final ObjectId revid = repo.resolve(baseRevision);
	if (revid == null) {
	throw new InvalidRevisionException();
	}
	return revid;
	} catch (IOException err) {
	log.error("Cannot resolve \"" + baseRevision + "\" in project \""
	+ projectName.get() + "\"", err);
	throw new InvalidRevisionException();
	} catch (RevisionSyntaxException err) {
	log.error("Invalid revision syntax \"" + baseRevision + "\"", err);
	throw new InvalidRevisionException();
	}
	}

	private RevWalk verifyConnected(final Repository repo, final ObjectId revid)
	throws InvalidRevisionException {
	try {
	final ObjectWalk rw = new ObjectWalk(repo);
	try {
	rw.markStart(rw.parseCommit(revid));
	} catch (IncorrectObjectTypeException err) {
	throw new InvalidRevisionException();
	}
	RefDatabase refDb = repo.getRefDatabase();
	Iterable<Ref> refs = Iterables.concat(
	refDb.getRefs(Constants.R_HEADS).values(),
	refDb.getRefs(Constants.R_TAGS).values());
	Ref rc = refDb.getRef(RefNames.REFS_CONFIG);
	if (rc != null) {
	refs = Iterables.concat(refs, Collections.singleton(rc));
	}
	for (Ref r : refs) {
	try {
	rw.markUninteresting(rw.parseAny(r.getObjectId()));
	} catch (MissingObjectException err) {
	continue;
	}
	}
	rw.checkConnectivity();
	return rw;
	} catch (IncorrectObjectTypeException err) {
	throw new InvalidRevisionException();
	} catch (MissingObjectException err) {
	throw new InvalidRevisionException();
	} catch (IOException err) {
	log.error("Repository \"" + repo.getDirectory()
	+ "\" may be corrupt; suggest running git fsck", err);
	throw new InvalidRevisionException();
	}
	}
	}