Examples with Promise com.twitter.util.Promise used on opensource projects

Example 16 with Promise

use of com.twitter.util.Promise in project distributedlog by twitter.

the class TestZKLogSegmentMetadataStore method testStoreMaxLogSegmentSequenceNumberOnNonExistentPath.

@Test(timeout = 60000)
public void testStoreMaxLogSegmentSequenceNumberOnNonExistentPath() throws Exception {
    Transaction<Object> updateTxn = lsmStore.transaction();
    Versioned<Long> value = new Versioned<Long>(999L, new ZkVersion(10));
    final Promise<Version> result = new Promise<Version>();
    String nonExistentPath = rootZkPath + "/non-existent";
    lsmStore.storeMaxLogSegmentSequenceNumber(updateTxn, nonExistentPath, value, new Transaction.OpListener<Version>() {

        @Override
        public void onCommit(Version r) {
            result.setValue(r);
        }

        @Override
        public void onAbort(Throwable t) {
            result.setException(t);
        }
    });
    try {
        FutureUtils.result(updateTxn.execute());
        fail("Should fail on storing log segment sequence number if path doesn't exist");
    } catch (ZKException zke) {
        assertEquals(KeeperException.Code.NONODE, zke.getKeeperExceptionCode());
    }
    try {
        Await.result(result);
        fail("Should fail on storing log segment sequence number if path doesn't exist");
    } catch (KeeperException ke) {
        assertEquals(KeeperException.Code.NONODE, ke.code());
    }
}

Example 17 with Promise

use of com.twitter.util.Promise in project distributedlog by twitter.

the class TestZKLogSegmentMetadataStore method testStoreMaxLogSegmentSequenceNumber.

@Test(timeout = 60000)
public void testStoreMaxLogSegmentSequenceNumber() throws Exception {
    Transaction<Object> updateTxn = lsmStore.transaction();
    Versioned<Long> value = new Versioned<Long>(999L, new ZkVersion(0));
    final Promise<Version> result = new Promise<Version>();
    lsmStore.storeMaxLogSegmentSequenceNumber(updateTxn, rootZkPath, value, new Transaction.OpListener<Version>() {

        @Override
        public void onCommit(Version r) {
            result.setValue(r);
        }

        @Override
        public void onAbort(Throwable t) {
            result.setException(t);
        }
    });
    FutureUtils.result(updateTxn.execute());
    assertEquals(1, ((ZkVersion) FutureUtils.result(result)).getZnodeVersion());
    Stat stat = new Stat();
    byte[] data = zkc.get().getData(rootZkPath, false, stat);
    assertEquals(999L, DLUtils.deserializeLogSegmentSequenceNumber(data));
    assertEquals(1, stat.getVersion());
}

Example 18 with Promise

use of com.twitter.util.Promise in project distributedlog by twitter.

the class LedgerAllocatorPool method tryObtain.

@Override
public Future<LedgerHandle> tryObtain(final Transaction<Object> txn, final Transaction.OpListener<LedgerHandle> listener) {
    final SimpleLedgerAllocator allocator;
    synchronized (this) {
        if (allocatingList.isEmpty()) {
            return Future.exception(new IOException("No ledger allocator available under " + poolPath + "."));
        } else {
            allocator = allocatingList.removeFirst();
        }
    }
    final Promise<LedgerHandle> tryObtainPromise = new Promise<LedgerHandle>();
    final FutureEventListener<LedgerHandle> tryObtainListener = new FutureEventListener<LedgerHandle>() {

        @Override
        public void onSuccess(LedgerHandle lh) {
            synchronized (LedgerAllocatorPool.this) {
                obtainMap.put(lh, allocator);
                reverseObtainMap.put(allocator, lh);
                tryObtainPromise.setValue(lh);
            }
        }

        @Override
        public void onFailure(Throwable cause) {
            try {
                rescueAllocator(allocator);
            } catch (IOException ioe) {
                logger.info("Failed to rescue allocator {}", allocator.allocatePath, ioe);
            }
            tryObtainPromise.setException(cause);
        }
    };
    allocator.tryObtain(txn, new Transaction.OpListener<LedgerHandle>() {

        @Override
        public void onCommit(LedgerHandle lh) {
            confirmObtain(allocator);
            listener.onCommit(lh);
        }

        @Override
        public void onAbort(Throwable t) {
            abortObtain(allocator);
            listener.onAbort(t);
        }
    }).addEventListener(tryObtainListener);
    return tryObtainPromise;
}

Example 19 with Promise

use of com.twitter.util.Promise in project distributedlog by twitter.

the class ReadUtils method asyncReadRecordFromEntries.

/**
     * Read record from a given range of ledger entries.
     *
     * @param streamName
     *          fully qualified stream name (used for logging)
     * @param ledgerDescriptor
     *          ledger descriptor.
     * @param handleCache
     *          ledger handle cache.
     * @param executorService
     *          executor service used for processing entries
     * @param context
     *          scan context
     * @return a future with the log record.
     */
private static Future<LogRecordWithDLSN> asyncReadRecordFromEntries(final String streamName, final LedgerDescriptor ledgerDescriptor, LedgerHandleCache handleCache, final LogSegmentMetadata metadata, final ExecutorService executorService, final ScanContext context, final LogRecordSelector selector) {
    final Promise<LogRecordWithDLSN> promise = new Promise<LogRecordWithDLSN>();
    final long startEntryId = context.curStartEntryId.get();
    final long endEntryId = context.curEndEntryId.get();
    if (LOG.isDebugEnabled()) {
        LOG.debug("{} reading entries [{} - {}] from {}.", new Object[] { streamName, startEntryId, endEntryId, ledgerDescriptor });
    }
    FutureEventListener<Enumeration<LedgerEntry>> readEntriesListener = new FutureEventListener<Enumeration<LedgerEntry>>() {

        @Override
        public void onSuccess(final Enumeration<LedgerEntry> entries) {
            if (LOG.isDebugEnabled()) {
                LOG.debug("{} finished reading entries [{} - {}] from {}", new Object[] { streamName, startEntryId, endEntryId, ledgerDescriptor });
            }
            LogRecordWithDLSN record = null;
            while (entries.hasMoreElements()) {
                LedgerEntry entry = entries.nextElement();
                try {
                    visitEntryRecords(streamName, metadata, ledgerDescriptor.getLogSegmentSequenceNo(), entry, context, selector);
                } catch (IOException ioe) {
                    // exception is only thrown due to bad ledger entry, so it might be corrupted
                    // we shouldn't do anything beyond this point. throw the exception to application
                    promise.setException(ioe);
                    return;
                }
            }
            record = selector.result();
            if (LOG.isDebugEnabled()) {
                LOG.debug("{} got record from entries [{} - {}] of {} : {}", new Object[] { streamName, startEntryId, endEntryId, ledgerDescriptor, record });
            }
            promise.setValue(record);
        }

        @Override
        public void onFailure(final Throwable cause) {
            String errMsg = "Error reading entries [" + startEntryId + "-" + endEntryId + "] for reading record of " + streamName;
            promise.setException(new IOException(errMsg, BKException.create(FutureUtils.bkResultCode(cause))));
        }
    };
    handleCache.asyncReadEntries(ledgerDescriptor, startEntryId, endEntryId).addEventListener(FutureEventListenerRunnable.of(readEntriesListener, executorService));
    return promise;
}

Example 20 with Promise

use of com.twitter.util.Promise in project distributedlog by twitter.

the class ZKSubscriptionStateStore method getLastCommitPositionFromZK.

Future<DLSN> getLastCommitPositionFromZK() {
    final Promise<DLSN> result = new Promise<DLSN>();
    try {
        logger.debug("Reading last commit position from path {}", zkPath);
        zooKeeperClient.get().getData(zkPath, false, new AsyncCallback.DataCallback() {

            @Override
            public void processResult(int rc, String path, Object ctx, byte[] data, Stat stat) {
                logger.debug("Read last commit position from path {}: rc = {}", zkPath, rc);
                if (KeeperException.Code.NONODE.intValue() == rc) {
                    result.setValue(DLSN.NonInclusiveLowerBound);
                } else if (KeeperException.Code.OK.intValue() != rc) {
                    result.setException(KeeperException.create(KeeperException.Code.get(rc), path));
                } else {
                    try {
                        DLSN dlsn = DLSN.deserialize(new String(data, Charsets.UTF_8));
                        result.setValue(dlsn);
                    } catch (Exception t) {
                        logger.warn("Invalid last commit position found from path {}", zkPath, t);
                        // invalid dlsn recorded in subscription state store
                        result.setValue(DLSN.NonInclusiveLowerBound);
                    }
                }
            }
        }, null);
    } catch (ZooKeeperClient.ZooKeeperConnectionException zkce) {
        result.setException(zkce);
    } catch (InterruptedException ie) {
        result.setException(new DLInterruptedException("getLastCommitPosition was interrupted", ie));
    }
    return result;
}