/**
* Update this metadata branch, recording a new commit on its reference.
*
* @param update helper information to define the update that will occur.
* @return the commit that was created
* @throws IOException if there is a storage problem and the update cannot be executed as
* requested or if it failed because of a concurrent update to the same reference
*/
public RevCommit commit(MetaDataUpdate update) throws IOException {
BatchMetaDataUpdate batch = openUpdate(update);
try {
batch.write(update.getCommitBuilder());
return batch.commit();
} finally {
batch.close();
}
}
/**
* Creates a new commit and a new ref based on this commit.
*
* @param update helper information to define the update that will occur.
* @param refName name of the ref that should be created
* @return the commit that was created
* @throws IOException if there is a storage problem and the update cannot be executed as
* requested or if it failed because of a concurrent update to the same reference
*/
public RevCommit commitToNewRef(MetaDataUpdate update, String refName) throws IOException {
BatchMetaDataUpdate batch = openUpdate(update);
try {
batch.write(update.getCommitBuilder());
return batch.createRef(refName);
} finally {
batch.close();
}
}
/**
* Open a batch of updates to the same metadata ref.
*
* <p>This allows making multiple commits to a single metadata ref, at the end of which is a
* single ref update. For batching together updates to multiple refs (each consisting of one or
* more commits against their respective refs), create the {@link MetaDataUpdate} with a {@link
* BatchRefUpdate}.
*
* <p>A ref update produced by this {@link BatchMetaDataUpdate} is only committed if there is no
* associated {@link BatchRefUpdate}. As a result, the configured ref updated event is not fired
* if there is an associated batch.
*
* @param update helper info about the update.
* @throws IOException if the update failed.
*/
public BatchMetaDataUpdate openUpdate(final MetaDataUpdate update) throws IOException {
final Repository db = update.getRepository();
reader = db.newObjectReader();
inserter = db.newObjectInserter();
final RevWalk rw = new RevWalk(reader);
final RevTree tree = revision != null ? rw.parseTree(revision) : null;
newTree = readTree(tree);
return new BatchMetaDataUpdate() {
AnyObjectId src = revision;
AnyObjectId srcTree = tree;
@Override
public void write(CommitBuilder commit) throws IOException {
write(VersionedMetaData.this, commit);
}
private boolean doSave(VersionedMetaData config, CommitBuilder commit) throws IOException {
DirCache nt = config.newTree;
ObjectReader r = config.reader;
ObjectInserter i = config.inserter;
try {
config.newTree = newTree;
config.reader = reader;
config.inserter = inserter;
return config.onSave(commit);
} catch (ConfigInvalidException e) {
throw new IOException(
"Cannot update " + getRefName() + " in " + db.getDirectory() + ": " + e.getMessage(),
e);
} finally {
config.newTree = nt;
config.reader = r;
config.inserter = i;
}
}
@Override
public void write(VersionedMetaData config, CommitBuilder commit) throws IOException {
if (!doSave(config, commit)) {
return;
}
// Reuse tree from parent commit unless there are contents in newTree or
// there is no tree for a parent commit.
ObjectId res =
newTree.getEntryCount() != 0 || srcTree == null
? newTree.writeTree(inserter)
: srcTree.copy();
if (res.equals(srcTree) && !update.allowEmpty() && (commit.getTreeId() == null)) {
// If there are no changes to the content, don't create the commit.
return;
}
// If changes are made to the DirCache and those changes are written as
// a commit and then the tree ID is set for the CommitBuilder, then
// those previous DirCache changes will be ignored and the commit's
// tree will be replaced with the ID in the CommitBuilder. The same is
// true if you explicitly set tree ID in a commit and then make changes
// to the DirCache; that tree ID will be ignored and replaced by that of
// the tree for the updated DirCache.
if (commit.getTreeId() == null) {
commit.setTreeId(res);
} else {
// In this case, the caller populated the tree without using DirCache.
res = commit.getTreeId();
}
if (src != null) {
commit.addParentId(src);
}
if (update.insertChangeId()) {
ObjectId id =
ChangeIdUtil.computeChangeId(
res,
getRevision(),
commit.getAuthor(),
commit.getCommitter(),
commit.getMessage());
commit.setMessage(ChangeIdUtil.insertId(commit.getMessage(), id));
}
src = inserter.insert(commit);
srcTree = res;
}
@Override
public RevCommit createRef(String refName) throws IOException {
if (Objects.equals(src, revision)) {
return revision;
}
return updateRef(ObjectId.zeroId(), src, refName);
}
@Override
public void removeRef(String refName) throws IOException {
RefUpdate ru = db.updateRef(refName);
ru.setForceUpdate(true);
if (revision != null) {
ru.setExpectedOldObjectId(revision);
}
RefUpdate.Result result = ru.delete();
switch (result) {
case FORCED:
update.fireGitRefUpdatedEvent(ru);
return;
case FAST_FORWARD:
case IO_FAILURE:
case LOCK_FAILURE:
case NEW:
case NOT_ATTEMPTED:
case NO_CHANGE:
case REJECTED:
case REJECTED_CURRENT_BRANCH:
case RENAMED:
default:
throw new IOException(
"Cannot delete "
+ ru.getName()
+ " in "
+ db.getDirectory()
+ ": "
+ ru.getResult());
}
}
@Override
public RevCommit commit() throws IOException {
return commitAt(revision);
}
@Override
public RevCommit commitAt(ObjectId expected) throws IOException {
if (Objects.equals(src, expected)) {
return revision;
}
return updateRef(MoreObjects.firstNonNull(expected, ObjectId.zeroId()), src, getRefName());
}
@Override
public void close() {
newTree = null;
rw.close();
if (inserter != null) {
inserter.close();
inserter = null;
}
if (reader != null) {
reader.close();
reader = null;
}
}
private RevCommit updateRef(AnyObjectId oldId, AnyObjectId newId, String refName)
throws IOException {
BatchRefUpdate bru = update.getBatch();
if (bru != null) {
bru.addCommand(new ReceiveCommand(oldId.toObjectId(), newId.toObjectId(), refName));
inserter.flush();
revision = rw.parseCommit(newId);
return revision;
}
RefUpdate ru = db.updateRef(refName);
ru.setExpectedOldObjectId(oldId);
ru.setNewObjectId(src);
ru.setRefLogIdent(update.getCommitBuilder().getAuthor());
String message = update.getCommitBuilder().getMessage();
if (message == null) {
message = "meta data update";
}
try (BufferedReader reader = new BufferedReader(new StringReader(message))) {
// read the subject line and use it as reflog message
ru.setRefLogMessage("commit: " + reader.readLine(), true);
}
inserter.flush();
RefUpdate.Result result = ru.update();
switch (result) {
case NEW:
case FAST_FORWARD:
revision = rw.parseCommit(ru.getNewObjectId());
update.fireGitRefUpdatedEvent(ru);
return revision;
case FORCED:
case IO_FAILURE:
case LOCK_FAILURE:
case NOT_ATTEMPTED:
case NO_CHANGE:
case REJECTED:
case REJECTED_CURRENT_BRANCH:
case RENAMED:
default:
throw new IOException(
"Cannot update "
+ ru.getName()
+ " in "
+ db.getDirectory()
+ ": "
+ ru.getResult());
}
}
};
}
public void load(MetaDataUpdate update, ObjectId id) throws IOException, ConfigInvalidException {
load(update.getRepository(), id);
}
