Examples with TxnResource io.pravega.controller.store.task.TxnResource used on opensource projects

Example 1 with TxnResource

use of io.pravega.controller.store.task.TxnResource in project pravega by pravega.

the class StreamTransactionMetadataTasks method createTxnBody.

/**
 * Creates txn on the specified stream.
 *
 * Post-condition:
 * 1. If txn creation succeeds, then
 *     (a) txn node is created in the store,
 *     (b) txn segments are successfully created on respective segment stores,
 *     (c) txn is present in the host-txn index of current host,
 *     (d) txn's timeout is being tracked in timeout service.
 *
 * 2. If process fails after creating txn node, but before responding to the client, then since txn is
 * present in the host-txn index, some other controller process shall abort the txn after maxLeaseValue
 *
 * 3. If timeout service tracks timeout of specified txn,
 * then txn is also present in the host-txn index of current process.
 *
 * Invariant:
 * The following invariants are maintained throughout the execution of createTxn, pingTxn and sealTxn methods.
 * 1. If timeout service tracks timeout of a txn, then txn is also present in the host-txn index of current process.
 * 2. If txn znode is updated, then txn is also present in the host-txn index of current process.
 *
 * @param scope               scope name.
 * @param stream              stream name.
 * @param lease               txn lease.
 * @param scaleGracePeriod    amount of time for which txn may remain open after scale operation is initiated.
 * @param ctx                 context.
 * @return                    identifier of the created txn.
 */
CompletableFuture<Pair<VersionedTransactionData, List<Segment>>> createTxnBody(final String scope, final String stream, final long lease, final long scaleGracePeriod, final OperationContext ctx) {
    // Step 1. Validate parameters.
    CompletableFuture<Void> validate = validate(lease, scaleGracePeriod);
    long maxExecutionPeriod = Math.min(MAX_EXECUTION_TIME_MULTIPLIER * lease, Duration.ofDays(1).toMillis());
    UUID txnId = UUID.randomUUID();
    TxnResource resource = new TxnResource(scope, stream, txnId);
    // Step 2. Add txn to host-transaction index.
    CompletableFuture<Void> addIndex = validate.thenComposeAsync(ignore -> streamMetadataStore.addTxnToIndex(hostId, resource, 0), executor).whenComplete((v, e) -> {
        if (e != null) {
            log.debug("Txn={}, failed adding txn to host-txn index of host={}", txnId, hostId);
        } else {
            log.debug("Txn={}, added txn to host-txn index of host={}", txnId, hostId);
        }
    });
    // Step 3. Create txn node in the store.
    CompletableFuture<VersionedTransactionData> txnFuture = addIndex.thenComposeAsync(ignore -> streamMetadataStore.createTransaction(scope, stream, txnId, lease, maxExecutionPeriod, scaleGracePeriod, ctx, executor), executor).whenComplete((v, e) -> {
        if (e != null) {
            log.debug("Txn={}, failed creating txn in store", txnId);
        } else {
            log.debug("Txn={}, created in store", txnId);
        }
    });
    // Step 4. Notify segment stores about new txn.
    CompletableFuture<List<Segment>> segmentsFuture = txnFuture.thenComposeAsync(txnData -> streamMetadataStore.getActiveSegments(scope, stream, txnData.getEpoch(), ctx, executor), executor);
    CompletableFuture<Void> notify = segmentsFuture.thenComposeAsync(activeSegments -> notifyTxnCreation(scope, stream, activeSegments, txnId), executor).whenComplete((v, e) -> log.debug("Txn={}, notified segments stores", txnId));
    // Step 5. Start tracking txn in timeout service
    return notify.whenCompleteAsync((result, ex) -> {
        int version = 0;
        long executionExpiryTime = System.currentTimeMillis() + maxExecutionPeriod;
        if (!txnFuture.isCompletedExceptionally()) {
            version = txnFuture.join().getVersion();
            executionExpiryTime = txnFuture.join().getMaxExecutionExpiryTime();
        }
        timeoutService.addTxn(scope, stream, txnId, version, lease, executionExpiryTime, scaleGracePeriod);
        log.debug("Txn={}, added to timeout service on host={}", txnId, hostId);
    }, executor).thenApplyAsync(v -> new ImmutablePair<>(txnFuture.join(), segmentsFuture.join()), executor);
}

Example 2 with TxnResource

use of io.pravega.controller.store.task.TxnResource in project pravega by pravega.

the class StreamTransactionMetadataTasks method sealTxnBody.

/**
 * Seals a txn and transitions it to COMMITTING (resp. ABORTING) state if commit param is true (resp. false).
 *
 * Post-condition:
 * 1. If seal completes successfully, then
 *     (a) txn state is COMMITTING/ABORTING,
 *     (b) CommitEvent/AbortEvent is present in the commit stream/abort stream,
 *     (c) txn is removed from host-txn index,
 *     (d) txn is removed from the timeout service.
 *
 * 2. If process fails after transitioning txn to COMMITTING/ABORTING state, but before responding to client, then
 * since txn is present in the host-txn index, some other controller process shall put CommitEvent/AbortEvent to
 * commit stream/abort stream.
 *
 * @param host    host id. It is different from hostId iff invoked from TxnSweeper for aborting orphaned txn.
 * @param scope   scope name.
 * @param stream  stream name.
 * @param commit  boolean indicating whether to commit txn.
 * @param txnId   txn id.
 * @param version expected version of txn node in store.
 * @param ctx     context.
 * @return        Txn status after sealing it.
 */
CompletableFuture<TxnStatus> sealTxnBody(final String host, final String scope, final String stream, final boolean commit, final UUID txnId, final Version version, final String writerId, final long timestamp, final OperationContext ctx) {
    Preconditions.checkNotNull(ctx, "Operation context cannot be null");
    long requestId = ctx.getRequestId();
    TxnResource resource = new TxnResource(scope, stream, txnId);
    Optional<Version> versionOpt = Optional.ofNullable(version);
    // Step 1. Add txn to current host's index, if it is not already present
    CompletableFuture<Void> addIndex = host.equals(hostId) && !timeoutService.containsTxn(scope, stream, txnId) ? // then txn would no longer be open.
    streamMetadataStore.addTxnToIndex(hostId, resource, version) : CompletableFuture.completedFuture(null);
    addIndex.whenComplete((v, e) -> {
        if (e != null) {
            log.debug(requestId, "Txn={}, already present/newly added to host-txn index of host={}", txnId, hostId);
        } else {
            log.debug(requestId, "Txn={}, added txn to host-txn index of host={}", txnId, hostId);
        }
    });
    // Step 2. Seal txn
    CompletableFuture<AbstractMap.SimpleEntry<TxnStatus, Integer>> sealFuture = addIndex.thenComposeAsync(x -> streamMetadataStore.sealTransaction(scope, stream, txnId, commit, versionOpt, writerId, timestamp, ctx, executor), executor).whenComplete((v, e) -> {
        if (e != null) {
            log.debug(requestId, "Txn={}, failed sealing txn", txnId);
        } else {
            log.debug(requestId, "Txn={}, sealed successfully, commit={}", txnId, commit);
        }
    });
    // Step 3. write event to corresponding stream.
    return sealFuture.thenComposeAsync(pair -> {
        TxnStatus status = pair.getKey();
        switch(status) {
            case COMMITTING:
                return writeCommitEvent(scope, stream, pair.getValue(), txnId, status, requestId);
            case ABORTING:
                return writeAbortEvent(scope, stream, pair.getValue(), txnId, status, requestId);
            case ABORTED:
            case COMMITTED:
                return CompletableFuture.completedFuture(status);
            case OPEN:
            case UNKNOWN:
            default:
                // exception would be thrown.
                return CompletableFuture.completedFuture(status);
        }
    }, executor).thenComposeAsync(status -> {
        // Step 4. Remove txn from timeoutService, and from the index.
        timeoutService.removeTxn(scope, stream, txnId);
        log.debug(requestId, "Txn={}, removed from timeout service", txnId);
        return streamMetadataStore.removeTxnFromIndex(host, resource, true).whenComplete((v, e) -> {
            if (e != null) {
                log.debug(requestId, "Txn={}, failed removing txn from host-txn index of host={}", txnId, hostId);
            } else {
                log.debug(requestId, "Txn={}, removed txn from host-txn index of host={}", txnId, hostId);
            }
        }).thenApply(x -> status);
    }, executor);
}

Example 3 with TxnResource

use of io.pravega.controller.store.task.TxnResource in project pravega by pravega.

the class TxnSweeper method failOverTxn.

private CompletableFuture<Result> failOverTxn(String failedHost, TxnResource txn) {
    String scope = txn.getScope();
    String stream = txn.getStream();
    UUID txnId = txn.getTxnId();
    log.info("Host = {}, processing transaction {}/{}/{}", failedHost, scope, stream, txnId);
    return streamMetadataStore.getTransactionData(scope, stream, txnId, null, executor).handle((r, e) -> {
        if (e != null) {
            if (Exceptions.unwrap(e) instanceof StoreException.DataNotFoundException) {
                // transaction not found, which means it should already have completed. We will ignore such txns
                return VersionedTransactionData.EMPTY;
            } else {
                throw new CompletionException(e);
            }
        }
        return r;
    }).thenComposeAsync(txData -> {
        int epoch = txData.getEpoch();
        switch(txData.getStatus()) {
            case OPEN:
                return failOverOpenTxn(failedHost, txn).handleAsync((v, e) -> new Result(txn, v, e), executor);
            case ABORTING:
                return failOverAbortingTxn(failedHost, epoch, txn).handleAsync((v, e) -> new Result(txn, v, e), executor);
            case COMMITTING:
                return failOverCommittingTxn(failedHost, epoch, txn).handleAsync((v, e) -> new Result(txn, v, e), executor);
            case UNKNOWN:
            default:
                return streamMetadataStore.removeTxnFromIndex(failedHost, txn, true).thenApply(x -> new Result(txn, null, null));
        }
    }, executor).whenComplete((v, e) -> log.debug("Host = {}, processing transaction {}/{}/{} complete", failedHost, scope, stream, txnId));
}

Example 4 with TxnResource

use of io.pravega.controller.store.task.TxnResource in project pravega by pravega.

the class StreamMetadataStoreTest method txnHostIndexTest.

@Test(timeout = 30000)
public void txnHostIndexTest() {
    String host1 = "host1";
    String host2 = "host2";
    TxnResource txn1 = new TxnResource(scope, stream1, UUID.randomUUID());
    TxnResource txn2 = new TxnResource(scope, stream1, UUID.randomUUID());
    addTxnToHost(host1, txn1, new Version.IntVersion(0));
    Assert.assertEquals(1, store.listHostsOwningTxn().join().size());
    Optional<TxnResource> txn = store.getRandomTxnFromIndex(host1).join();
    Assert.assertTrue(txn.isPresent());
    Assert.assertEquals(txn1.getTxnId().toString(), txn.get().getTxnId().toString());
    // Adding a txn again should not fail.
    addTxnToHost(host1, txn1, new Version.IntVersion(0));
    addTxnToHost(host1, txn2, new Version.IntVersion(5));
    Assert.assertEquals(1, store.listHostsOwningTxn().join().size());
    // Fetching version of txn not existing in the index should return null.
    Assert.assertNull(store.getTxnVersionFromIndex(host1, new TxnResource(scope, stream1, UUID.randomUUID())).join());
    txn = store.getRandomTxnFromIndex(host1).join();
    Assert.assertTrue(txn.isPresent());
    UUID randomTxnId = txn.get().getTxnId();
    Assert.assertTrue(randomTxnId.equals(txn1.getTxnId()) || randomTxnId.equals(txn2.getTxnId()));
    Assert.assertEquals(scope, txn.get().getScope());
    Assert.assertEquals(stream1, txn.get().getStream());
    // Test remove txn from index.
    store.removeTxnFromIndex(host1, txn1, true).join();
    // Test remove is idempotent operation.
    store.removeTxnFromIndex(host1, txn1, true).join();
    // Test remove last txn from the index.
    store.removeTxnFromIndex(host1, txn2, false).join();
    Assert.assertEquals(1, store.listHostsOwningTxn().join().size());
    // Test remove is idempotent operation.
    store.removeTxnFromIndex(host1, txn2, true).join();
    Assert.assertTrue(store.listHostsOwningTxn().join().size() <= 1);
    // Test removal of txn that was never added.
    store.removeTxnFromIndex(host1, new TxnResource(scope, stream1, UUID.randomUUID()), true).join();
    // Test host removal.
    store.removeHostFromIndex(host1).join();
    Assert.assertEquals(0, store.listHostsOwningTxn().join().size());
    // Test host removal is idempotent.
    store.removeHostFromIndex(host1).join();
    Assert.assertEquals(0, store.listHostsOwningTxn().join().size());
    // Test removal of host that was never added.
    store.removeHostFromIndex(host2).join();
    Assert.assertEquals(0, store.listHostsOwningTxn().join().size());
}

Example 5 with TxnResource

use of io.pravega.controller.store.task.TxnResource in project pravega by pravega.

the class ZKStreamMetadataStoreTest method testError.

@Test(timeout = 5000)
public void testError() throws Exception {
    String host = "host";
    TxnResource txn = new TxnResource("SCOPE", "STREAM1", UUID.randomUUID());
    Predicate<Throwable> checker = (Throwable ex) -> ex instanceof StoreException.UnknownException;
    cli.close();
    testFailure(host, txn, checker);
}