/** * Creates a new file output stream. * * @param path the file path * @param options the client options * @throws IOException if an I/O error occurs */ public FileOutStream(TachyonURI path, OutStreamOptions options) throws IOException { mUri = Preconditions.checkNotNull(path); mNonce = ClientUtils.getRandomNonNegativeLong(); mBlockSize = options.getBlockSizeBytes(); mTachyonStorageType = options.getTachyonStorageType(); mUnderStorageType = options.getUnderStorageType(); mContext = FileSystemContext.INSTANCE; mPreviousBlockOutStreams = new LinkedList<BufferedBlockOutStream>(); if (mUnderStorageType.isSyncPersist()) { updateUfsPath(); String tmpPath = PathUtils.temporaryFileName(mNonce, mUfsPath); UnderFileSystem ufs = UnderFileSystem.get(tmpPath, ClientContext.getConf()); // TODO(jiri): Implement collection of temporary files left behind by dead clients. mUnderStorageOutputStream = ufs.create(tmpPath, (int) mBlockSize); } else { mUfsPath = null; mUnderStorageOutputStream = null; } mClosed = false; mCanceled = false; mShouldCacheCurrentBlock = mTachyonStorageType.isStore(); mBytesWritten = 0; mLocationPolicy = Preconditions.checkNotNull( options.getLocationPolicy(), PreconditionMessage.FILE_WRITE_LOCATION_POLICY_UNSPECIFIED); }
@Override public void flush() throws IOException { // TODO(yupeng): Handle flush for Tachyon storage stream as well. if (mUnderStorageType.isSyncPersist()) { mUnderStorageOutputStream.flush(); } }
protected void handleCacheWriteException(IOException ioe) throws IOException { if (!mUnderStorageType.isSyncPersist()) { throw new IOException(ExceptionMessage.FAILED_CACHE.getMessage(ioe.getMessage()), ioe); } LOG.warn("Failed to write into TachyonStore, canceling write attempt.", ioe); if (mCurrentBlockOutStream != null) { mShouldCacheCurrentBlock = false; mCurrentBlockOutStream.cancel(); } }
@Override public void write(int b) throws IOException { if (mShouldCacheCurrentBlock) { try { if (mCurrentBlockOutStream == null || mCurrentBlockOutStream.remaining() == 0) { getNextBlock(); } mCurrentBlockOutStream.write(b); } catch (IOException ioe) { handleCacheWriteException(ioe); } } if (mUnderStorageType.isSyncPersist()) { mUnderStorageOutputStream.write(b); ClientContext.getClientMetrics().incBytesWrittenUfs(1); } mBytesWritten++; }
@Override public void write(byte[] b, int off, int len) throws IOException { Preconditions.checkArgument(b != null, PreconditionMessage.ERR_WRITE_BUFFER_NULL); Preconditions.checkArgument( off >= 0 && len >= 0 && len + off <= b.length, PreconditionMessage.ERR_BUFFER_STATE, b.length, off, len); if (mShouldCacheCurrentBlock) { try { int tLen = len; int tOff = off; while (tLen > 0) { if (mCurrentBlockOutStream == null || mCurrentBlockOutStream.remaining() == 0) { getNextBlock(); } long currentBlockLeftBytes = mCurrentBlockOutStream.remaining(); if (currentBlockLeftBytes >= tLen) { mCurrentBlockOutStream.write(b, tOff, tLen); tLen = 0; } else { mCurrentBlockOutStream.write(b, tOff, (int) currentBlockLeftBytes); tOff += currentBlockLeftBytes; tLen -= currentBlockLeftBytes; } } } catch (IOException ioe) { handleCacheWriteException(ioe); } } if (mUnderStorageType.isSyncPersist()) { mUnderStorageOutputStream.write(b, off, len); ClientContext.getClientMetrics().incBytesWrittenUfs(len); } mBytesWritten += len; }
@Override public void close() throws IOException { if (mClosed) { return; } if (mCurrentBlockOutStream != null) { mPreviousBlockOutStreams.add(mCurrentBlockOutStream); } Boolean canComplete = false; CompleteFileOptions options = CompleteFileOptions.defaults(); if (mUnderStorageType.isSyncPersist()) { String tmpPath = PathUtils.temporaryFileName(mNonce, mUfsPath); UnderFileSystem ufs = UnderFileSystem.get(tmpPath, ClientContext.getConf()); if (mCanceled) { // TODO(yupeng): Handle this special case in under storage integrations. mUnderStorageOutputStream.close(); if (!ufs.exists(tmpPath)) { // Location of the temporary file has changed, recompute it. updateUfsPath(); tmpPath = PathUtils.temporaryFileName(mNonce, mUfsPath); } ufs.delete(tmpPath, false); } else { mUnderStorageOutputStream.flush(); mUnderStorageOutputStream.close(); if (!ufs.exists(tmpPath)) { // Location of the temporary file has changed, recompute it. updateUfsPath(); tmpPath = PathUtils.temporaryFileName(mNonce, mUfsPath); } if (!ufs.rename(tmpPath, mUfsPath)) { throw new IOException("Failed to rename " + tmpPath + " to " + mUfsPath); } options.setUfsLength(ufs.getFileSize(mUfsPath)); canComplete = true; } } if (mTachyonStorageType.isStore()) { try { if (mCanceled) { for (BufferedBlockOutStream bos : mPreviousBlockOutStreams) { bos.cancel(); } } else { for (BufferedBlockOutStream bos : mPreviousBlockOutStreams) { bos.close(); } canComplete = true; } } catch (IOException ioe) { handleCacheWriteException(ioe); } } if (canComplete) { FileSystemMasterClient masterClient = mContext.acquireMasterClient(); try { masterClient.completeFile(mUri, options); } catch (TachyonException e) { throw new IOException(e); } finally { mContext.releaseMasterClient(masterClient); } } if (mUnderStorageType.isAsyncPersist()) { scheduleAsyncPersist(); } mClosed = true; }