/**
* Combine the status stored in the index and the underlying status.
*
* @param h status stored in the index
* @param cache caching the underlying file statuses
* @return the combined file status
* @throws IOException
*/
private FileStatus toFileStatus(HarStatus h, Map<String, FileStatus> cache) throws IOException {
FileStatus underlying = null;
if (cache != null) {
underlying = cache.get(h.partName);
}
if (underlying == null) {
final Path p = h.isDir ? archivePath : new Path(archivePath, h.partName);
underlying = fs.getFileStatus(p);
if (cache != null) {
cache.put(h.partName, underlying);
}
}
long modTime = 0;
int version = metadata.getVersion();
if (version < 3) {
modTime = underlying.getModificationTime();
} else if (version == 3) {
modTime = h.getModificationTime();
}
return new FileStatus(
h.isDir() ? 0L : h.getLength(),
h.isDir(),
underlying.getReplication(),
underlying.getBlockSize(),
modTime,
underlying.getAccessTime(),
underlying.getPermission(),
underlying.getOwner(),
underlying.getGroup(),
makeRelative(this.uri.getPath(), new Path(h.name)));
}
/**
* Get block locations from the underlying fs and fix their offsets and lengths.
*
* @param file the input file status to get block locations
* @param start the start of the desired range in the contained file
* @param len the length of the desired range
* @return block locations for this segment of file
* @throws IOException
*/
@Override
public BlockLocation[] getFileBlockLocations(FileStatus file, long start, long len)
throws IOException {
HarStatus hstatus = getFileHarStatus(file.getPath());
Path partPath = new Path(archivePath, hstatus.getPartName());
FileStatus partStatus = metadata.getPartFileStatus(partPath);
// get all part blocks that overlap with the desired file blocks
BlockLocation[] locations =
fs.getFileBlockLocations(partStatus, hstatus.getStartIndex() + start, len);
return fixBlockLocations(locations, start, len, hstatus.getStartIndex());
}
/**
* Returns a har input stream which fakes end of file. It reads the index files to get the part
* file name and the size and start of the file.
*/
@Override
public FSDataInputStream open(Path f, int bufferSize) throws IOException {
// get the fs DataInputStream for the underlying file
HarStatus hstatus = getFileHarStatus(f);
if (hstatus.isDir()) {
throw new FileNotFoundException(f + " : not a file in " + archivePath);
}
return new HarFSDataInputStream(
fs,
new Path(archivePath, hstatus.getPartName()),
hstatus.getStartIndex(),
hstatus.getLength(),
bufferSize);
}
/**
* Get filestatuses of all the children of a given directory. This just reads through index file
* and reads line by line to get all statuses for children of a directory. Its a brute force way
* of getting all such filestatuses
*
* @param parent the parent path directory
* @param statuses the list to add the children filestatuses to
*/
private void fileStatusesInIndex(HarStatus parent, List<FileStatus> statuses) throws IOException {
String parentString = parent.getName();
if (!parentString.endsWith(Path.SEPARATOR)) {
parentString += Path.SEPARATOR;
}
Path harPath = new Path(parentString);
int harlen = harPath.depth();
final Map<String, FileStatus> cache = new TreeMap<String, FileStatus>();
for (HarStatus hstatus : metadata.archive.values()) {
String child = hstatus.getName();
if ((child.startsWith(parentString))) {
Path thisPath = new Path(child);
if (thisPath.depth() == harlen + 1) {
statuses.add(toFileStatus(hstatus, cache));
}
}
}
}
/** liststatus returns the children of a directory after looking up the index files. */
@Override
public FileStatus[] listStatus(Path f) throws IOException {
// need to see if the file is an index in file
// get the filestatus of the archive directory
// we will create fake filestatuses to return
// to the client
List<FileStatus> statuses = new ArrayList<FileStatus>();
Path tmpPath = makeQualified(f);
Path harPath = getPathInHar(tmpPath);
HarStatus hstatus = metadata.archive.get(harPath);
if (hstatus == null) {
throw new FileNotFoundException("File " + f + " not found in " + archivePath);
}
if (hstatus.isDir()) {
fileStatusesInIndex(hstatus, statuses);
} else {
statuses.add(toFileStatus(hstatus, null));
}
return statuses.toArray(new FileStatus[statuses.size()]);
}
