Examples with InputStreamCallback org.apache.nifi.processor.io.InputStreamCallback used on opensource projects

Example 46 with InputStreamCallback

use of org.apache.nifi.processor.io.InputStreamCallback in project nifi by apache.

the class ExtractTNEFAttachments method onTrigger.

@Override
public void onTrigger(final ProcessContext context, final ProcessSession session) {
    final ComponentLog logger = getLogger();
    final FlowFile originalFlowFile = session.get();
    if (originalFlowFile == null) {
        return;
    }
    final List<FlowFile> attachmentsList = new ArrayList<>();
    final List<FlowFile> invalidFlowFilesList = new ArrayList<>();
    final List<FlowFile> originalFlowFilesList = new ArrayList<>();
    session.read(originalFlowFile, new InputStreamCallback() {

        @Override
        public void process(final InputStream rawIn) throws IOException {
            try (final InputStream in = new BufferedInputStream(rawIn)) {
                Properties props = new Properties();
                HMEFMessage hmefMessage = null;
                // This will trigger an exception in case content is not a TNEF.
                hmefMessage = new HMEFMessage(in);
                // Add otiginal flowfile (may revert later on in case of errors) //
                originalFlowFilesList.add(originalFlowFile);
                if (hmefMessage != null) {
                    // Attachments isn empty, proceeding.
                    if (!hmefMessage.getAttachments().isEmpty()) {
                        final String originalFlowFileName = originalFlowFile.getAttribute(CoreAttributes.FILENAME.key());
                        try {
                            for (final Attachment attachment : hmefMessage.getAttachments()) {
                                FlowFile split = session.create(originalFlowFile);
                                final Map<String, String> attributes = new HashMap<>();
                                if (StringUtils.isNotBlank(attachment.getLongFilename())) {
                                    attributes.put(CoreAttributes.FILENAME.key(), attachment.getFilename());
                                }
                                String parentUuid = originalFlowFile.getAttribute(CoreAttributes.UUID.key());
                                attributes.put(ATTACHMENT_ORIGINAL_UUID, parentUuid);
                                attributes.put(ATTACHMENT_ORIGINAL_FILENAME, originalFlowFileName);
                                // TODO: Extract Mime Type (HMEF doesn't seem to be able to get this info.
                                split = session.append(split, new OutputStreamCallback() {

                                    @Override
                                    public void process(OutputStream out) throws IOException {
                                        out.write(attachment.getContents());
                                    }
                                });
                                split = session.putAllAttributes(split, attributes);
                                attachmentsList.add(split);
                            }
                        } catch (FlowFileHandlingException e) {
                            // Something went wrong
                            // Removing splits that may have been created
                            session.remove(attachmentsList);
                            // Removing the original flow from its list
                            originalFlowFilesList.remove(originalFlowFile);
                            logger.error("Flowfile {} triggered error {} while processing message removing generated FlowFiles from sessions", new Object[] { originalFlowFile, e });
                            invalidFlowFilesList.add(originalFlowFile);
                        }
                    }
                }
            } catch (Exception e) {
                // Another error hit...
                // Removing the original flow from its list
                originalFlowFilesList.remove(originalFlowFile);
                logger.error("Could not parse the flowfile {} as an email, treating as failure", new Object[] { originalFlowFile, e });
                // Message is invalid or triggered an error during parsing
                invalidFlowFilesList.add(originalFlowFile);
            }
        }
    });
    session.transfer(attachmentsList, REL_ATTACHMENTS);
    // As per above code, originalFlowfile may be routed to invalid or
    // original depending on RFC2822 compliance.
    session.transfer(invalidFlowFilesList, REL_FAILURE);
    session.transfer(originalFlowFilesList, REL_ORIGINAL);
    // check if attachments have been extracted
    if (attachmentsList.size() != 0) {
        if (attachmentsList.size() > 10) {
            // If more than 10, summarise log
            logger.info("Split {} into {} files", new Object[] { originalFlowFile, attachmentsList.size() });
        } else {
            // Otherwise be more verbose and list each individual split
            logger.info("Split {} into {} files: {}", new Object[] { originalFlowFile, attachmentsList.size(), attachmentsList });
        }
    }
}

Example 47 with InputStreamCallback

use of org.apache.nifi.processor.io.InputStreamCallback in project nifi by apache.

the class FlowFileEvent method getBody.

@Override
public byte[] getBody() {
    synchronized (bodyLock) {
        if (!bodyLoaded) {
            if (flowFile.getSize() > Integer.MAX_VALUE) {
                throw new RuntimeException("Can't get body of Event because the backing FlowFile is too large (" + flowFile.getSize() + " bytes)");
            }
            final ByteArrayOutputStream baos = new ByteArrayOutputStream((int) flowFile.getSize());
            session.read(flowFile, new InputStreamCallback() {

                @Override
                public void process(InputStream in) throws IOException {
                    try (BufferedInputStream input = new BufferedInputStream(in)) {
                        StreamUtils.copy(input, baos);
                    }
                    baos.close();
                }
            });
            body = baos.toByteArray();
            bodyLoaded = true;
        }
    }
    return body;
}

Example 48 with InputStreamCallback

use of org.apache.nifi.processor.io.InputStreamCallback in project nifi by apache.

the class HashContent method onTrigger.

@Override
public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException {
    FlowFile flowFile = session.get();
    if (flowFile == null) {
        return;
    }
    final ComponentLog logger = getLogger();
    final String algorithm = context.getProperty(HASH_ALGORITHM).getValue();
    final MessageDigest digest;
    try {
        digest = MessageDigest.getInstance(algorithm);
    } catch (NoSuchAlgorithmException e) {
        logger.error("Failed to process {} due to {}; routing to failure", new Object[] { flowFile, e });
        session.transfer(flowFile, REL_FAILURE);
        return;
    }
    final AtomicReference<String> hashValueHolder = new AtomicReference<>(null);
    try {
        session.read(flowFile, new InputStreamCallback() {

            @Override
            public void process(final InputStream in) throws IOException {
                try (final DigestOutputStream digestOut = new DigestOutputStream(new NullOutputStream(), digest)) {
                    StreamUtils.copy(in, digestOut);
                    final byte[] hash = digest.digest();
                    final StringBuilder strb = new StringBuilder(hash.length * 2);
                    for (int i = 0; i < hash.length; i++) {
                        strb.append(Integer.toHexString((hash[i] & 0xFF) | 0x100).substring(1, 3));
                    }
                    hashValueHolder.set(strb.toString());
                }
            }
        });
        final String attributeName = context.getProperty(ATTRIBUTE_NAME).getValue();
        flowFile = session.putAttribute(flowFile, attributeName, hashValueHolder.get());
        logger.info("Successfully added attribute '{}' to {} with a value of {}; routing to success", new Object[] { attributeName, flowFile, hashValueHolder.get() });
        session.getProvenanceReporter().modifyAttributes(flowFile);
        session.transfer(flowFile, REL_SUCCESS);
    } catch (final ProcessException e) {
        logger.error("Failed to process {} due to {}; routing to failure", new Object[] { flowFile, e });
        session.transfer(flowFile, REL_FAILURE);
    }
}

Example 49 with InputStreamCallback

use of org.apache.nifi.processor.io.InputStreamCallback in project nifi by apache.

the class ParseSyslog method onTrigger.

@Override
public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException {
    FlowFile flowFile = session.get();
    if (flowFile == null) {
        return;
    }
    final String charsetName = context.getProperty(CHARSET).getValue();
    // If the parser already exists and uses the same charset, it does not need to be re-initialized
    if (parser == null || !parser.getCharsetName().equals(charsetName)) {
        parser = new SyslogParser(Charset.forName(charsetName));
    }
    final byte[] buffer = new byte[(int) flowFile.getSize()];
    session.read(flowFile, new InputStreamCallback() {

        @Override
        public void process(final InputStream in) throws IOException {
            StreamUtils.fillBuffer(in, buffer);
        }
    });
    final SyslogEvent event;
    try {
        event = parser.parseEvent(buffer, null);
    } catch (final ProcessException pe) {
        getLogger().error("Failed to parse {} as a Syslog message due to {}; routing to failure", new Object[] { flowFile, pe });
        session.transfer(flowFile, REL_FAILURE);
        return;
    }
    if (event == null || !event.isValid()) {
        getLogger().error("Failed to parse {} as a Syslog message: it does not conform to any of the RFC formats supported; routing to failure", new Object[] { flowFile });
        session.transfer(flowFile, REL_FAILURE);
        return;
    }
    final Map<String, String> attributes = new HashMap<>(8);
    attributes.put(SyslogAttributes.PRIORITY.key(), event.getPriority());
    attributes.put(SyslogAttributes.SEVERITY.key(), event.getSeverity());
    attributes.put(SyslogAttributes.FACILITY.key(), event.getFacility());
    attributes.put(SyslogAttributes.VERSION.key(), event.getVersion());
    attributes.put(SyslogAttributes.TIMESTAMP.key(), event.getTimeStamp());
    attributes.put(SyslogAttributes.HOSTNAME.key(), event.getHostName());
    attributes.put(SyslogAttributes.BODY.key(), event.getMsgBody());
    flowFile = session.putAllAttributes(flowFile, attributes);
    session.transfer(flowFile, REL_SUCCESS);
}

Example 50 with InputStreamCallback

use of org.apache.nifi.processor.io.InputStreamCallback in project nifi by apache.

the class PostHTTP method onTrigger.

@Override
public void onTrigger(final ProcessContext context, final ProcessSession session) {
    FlowFile firstFlowFile = session.get();
    if (firstFlowFile == null) {
        return;
    }
    final ComponentLog logger = getLogger();
    final String url = context.getProperty(URL).evaluateAttributeExpressions(firstFlowFile).getValue();
    try {
        new java.net.URL(url);
    } catch (final MalformedURLException e) {
        logger.error("After substituting attribute values for {}, URL is {}; this is not a valid URL, so routing to failure", new Object[] { firstFlowFile, url });
        firstFlowFile = session.penalize(firstFlowFile);
        session.transfer(firstFlowFile, REL_FAILURE);
        return;
    }
    final List<FlowFile> toSend = new ArrayList<>();
    toSend.add(firstFlowFile);
    final boolean sendAsFlowFile = context.getProperty(SEND_AS_FLOWFILE).asBoolean();
    final int compressionLevel = context.getProperty(COMPRESSION_LEVEL).asInteger();
    final String userAgent = context.getProperty(USER_AGENT).getValue();
    final RequestConfig.Builder requestConfigBuilder = RequestConfig.custom();
    requestConfigBuilder.setConnectionRequestTimeout(context.getProperty(DATA_TIMEOUT).asTimePeriod(TimeUnit.MILLISECONDS).intValue());
    requestConfigBuilder.setConnectTimeout(context.getProperty(CONNECTION_TIMEOUT).asTimePeriod(TimeUnit.MILLISECONDS).intValue());
    requestConfigBuilder.setRedirectsEnabled(false);
    requestConfigBuilder.setSocketTimeout(context.getProperty(DATA_TIMEOUT).asTimePeriod(TimeUnit.MILLISECONDS).intValue());
    final RequestConfig requestConfig = requestConfigBuilder.build();
    final StreamThrottler throttler = throttlerRef.get();
    final Double maxBatchBytes = context.getProperty(MAX_BATCH_SIZE).asDataSize(DataUnit.B);
    final AtomicLong bytesToSend = new AtomicLong(firstFlowFile.getSize());
    DestinationAccepts destinationAccepts = null;
    CloseableHttpClient client = null;
    final String transactionId = UUID.randomUUID().toString();
    final AtomicReference<String> dnHolder = new AtomicReference<>("none");
    final Config config = getConfig(url, context);
    final HttpClientConnectionManager conMan = config.getConnectionManager();
    final HttpClientBuilder clientBuilder = HttpClientBuilder.create();
    clientBuilder.setConnectionManager(conMan);
    clientBuilder.setUserAgent(userAgent);
    clientBuilder.addInterceptorFirst(new HttpResponseInterceptor() {

        @Override
        public void process(final HttpResponse response, final HttpContext httpContext) throws HttpException, IOException {
            final HttpCoreContext coreContext = HttpCoreContext.adapt(httpContext);
            final ManagedHttpClientConnection conn = coreContext.getConnection(ManagedHttpClientConnection.class);
            if (!conn.isOpen()) {
                return;
            }
            final SSLSession sslSession = conn.getSSLSession();
            if (sslSession != null) {
                final Certificate[] certChain = sslSession.getPeerCertificates();
                if (certChain == null || certChain.length == 0) {
                    throw new SSLPeerUnverifiedException("No certificates found");
                }
                try {
                    final X509Certificate cert = CertificateUtils.convertAbstractX509Certificate(certChain[0]);
                    dnHolder.set(cert.getSubjectDN().getName().trim());
                } catch (CertificateException e) {
                    final String msg = "Could not extract subject DN from SSL session peer certificate";
                    logger.warn(msg);
                    throw new SSLPeerUnverifiedException(msg);
                }
            }
        }
    });
    clientBuilder.disableAutomaticRetries();
    clientBuilder.disableContentCompression();
    final String username = context.getProperty(USERNAME).getValue();
    final String password = context.getProperty(PASSWORD).getValue();
    // set the credentials if appropriate
    if (username != null) {
        final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
        if (password == null) {
            credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username));
        } else {
            credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
        }
        clientBuilder.setDefaultCredentialsProvider(credentialsProvider);
    }
    // Set the proxy if specified
    if (context.getProperty(PROXY_HOST).isSet() && context.getProperty(PROXY_PORT).isSet()) {
        final String host = context.getProperty(PROXY_HOST).getValue();
        final int port = context.getProperty(PROXY_PORT).asInteger();
        clientBuilder.setProxy(new HttpHost(host, port));
    }
    client = clientBuilder.build();
    // determine whether or not destination accepts flowfile/gzip
    destinationAccepts = config.getDestinationAccepts();
    if (destinationAccepts == null) {
        try {
            destinationAccepts = getDestinationAcceptance(sendAsFlowFile, client, url, getLogger(), transactionId);
            config.setDestinationAccepts(destinationAccepts);
        } catch (final IOException e) {
            firstFlowFile = session.penalize(firstFlowFile);
            session.transfer(firstFlowFile, REL_FAILURE);
            logger.error("Unable to communicate with destination {} to determine whether or not it can accept " + "flowfiles/gzip; routing {} to failure due to {}", new Object[] { url, firstFlowFile, e });
            context.yield();
            return;
        }
    }
    // then we can get more flowfiles from the session up to MAX_BATCH_SIZE for the same URL
    if (sendAsFlowFile && (destinationAccepts.isFlowFileV3Accepted() || destinationAccepts.isFlowFileV2Accepted())) {
        toSend.addAll(session.get(new FlowFileFilter() {

            @Override
            public FlowFileFilterResult filter(FlowFile flowFile) {
                // if over MAX_BATCH_SIZE, then stop adding files
                if (bytesToSend.get() + flowFile.getSize() > maxBatchBytes) {
                    return FlowFileFilterResult.REJECT_AND_TERMINATE;
                }
                // check URL to see if this flowfile can be included in the batch
                final String urlToCheck = context.getProperty(URL).evaluateAttributeExpressions(flowFile).getValue();
                if (url.equals(urlToCheck)) {
                    bytesToSend.addAndGet(flowFile.getSize());
                    return FlowFileFilterResult.ACCEPT_AND_CONTINUE;
                } else {
                    return FlowFileFilterResult.REJECT_AND_CONTINUE;
                }
            }
        }));
    }
    final HttpPost post = new HttpPost(url);
    final DestinationAccepts accepts = destinationAccepts;
    final boolean isDestinationLegacyNiFi = accepts.getProtocolVersion() == null;
    final EntityTemplate entity = new EntityTemplate(new ContentProducer() {

        @Override
        public void writeTo(final OutputStream rawOut) throws IOException {
            final OutputStream throttled = throttler == null ? rawOut : throttler.newThrottledOutputStream(rawOut);
            OutputStream wrappedOut = new BufferedOutputStream(throttled);
            if (compressionLevel > 0 && accepts.isGzipAccepted()) {
                wrappedOut = new GZIPOutputStream(wrappedOut, compressionLevel);
            }
            try (final OutputStream out = wrappedOut) {
                for (final FlowFile flowFile : toSend) {
                    session.read(flowFile, new InputStreamCallback() {

                        @Override
                        public void process(final InputStream rawIn) throws IOException {
                            try (final InputStream in = new BufferedInputStream(rawIn)) {
                                FlowFilePackager packager = null;
                                if (!sendAsFlowFile) {
                                    packager = null;
                                } else if (accepts.isFlowFileV3Accepted()) {
                                    packager = new FlowFilePackagerV3();
                                } else if (accepts.isFlowFileV2Accepted()) {
                                    packager = new FlowFilePackagerV2();
                                } else if (accepts.isFlowFileV1Accepted()) {
                                    packager = new FlowFilePackagerV1();
                                }
                                // formats is acceptable if sending as FlowFile.
                                if (packager == null) {
                                    StreamUtils.copy(in, out);
                                } else {
                                    final Map<String, String> flowFileAttributes;
                                    if (isDestinationLegacyNiFi) {
                                        // Old versions of NiFi expect nf.file.name and nf.file.path to indicate filename & path;
                                        // in order to maintain backward compatibility, we copy the filename & path to those attribute keys.
                                        flowFileAttributes = new HashMap<>(flowFile.getAttributes());
                                        flowFileAttributes.put("nf.file.name", flowFile.getAttribute(CoreAttributes.FILENAME.key()));
                                        flowFileAttributes.put("nf.file.path", flowFile.getAttribute(CoreAttributes.PATH.key()));
                                    } else {
                                        flowFileAttributes = flowFile.getAttributes();
                                    }
                                    packager.packageFlowFile(in, out, flowFileAttributes, flowFile.getSize());
                                }
                            }
                        }
                    });
                }
                out.flush();
            }
        }
    }) {

        @Override
        public long getContentLength() {
            if (compressionLevel == 0 && !sendAsFlowFile && !context.getProperty(CHUNKED_ENCODING).asBoolean()) {
                return toSend.get(0).getSize();
            } else {
                return -1;
            }
        }
    };
    if (context.getProperty(CHUNKED_ENCODING).isSet()) {
        entity.setChunked(context.getProperty(CHUNKED_ENCODING).asBoolean());
    }
    post.setEntity(entity);
    post.setConfig(requestConfig);
    final String contentType;
    if (sendAsFlowFile) {
        if (accepts.isFlowFileV3Accepted()) {
            contentType = APPLICATION_FLOW_FILE_V3;
        } else if (accepts.isFlowFileV2Accepted()) {
            contentType = APPLICATION_FLOW_FILE_V2;
        } else if (accepts.isFlowFileV1Accepted()) {
            contentType = APPLICATION_FLOW_FILE_V1;
        } else {
            logger.error("Cannot send data to {} because the destination does not accept FlowFiles and this processor is " + "configured to deliver FlowFiles; rolling back session", new Object[] { url });
            session.rollback();
            context.yield();
            IOUtils.closeQuietly(client);
            return;
        }
    } else {
        final String contentTypeValue = context.getProperty(CONTENT_TYPE).evaluateAttributeExpressions(toSend.get(0)).getValue();
        contentType = StringUtils.isBlank(contentTypeValue) ? DEFAULT_CONTENT_TYPE : contentTypeValue;
    }
    final String attributeHeaderRegex = context.getProperty(ATTRIBUTES_AS_HEADERS_REGEX).getValue();
    if (attributeHeaderRegex != null && !sendAsFlowFile && toSend.size() == 1) {
        final Pattern pattern = Pattern.compile(attributeHeaderRegex);
        final Map<String, String> attributes = toSend.get(0).getAttributes();
        for (final Map.Entry<String, String> entry : attributes.entrySet()) {
            final String key = entry.getKey();
            if (pattern.matcher(key).matches()) {
                post.setHeader(entry.getKey(), entry.getValue());
            }
        }
    }
    post.setHeader(CONTENT_TYPE_HEADER, contentType);
    post.setHeader(FLOWFILE_CONFIRMATION_HEADER, "true");
    post.setHeader(PROTOCOL_VERSION_HEADER, PROTOCOL_VERSION);
    post.setHeader(TRANSACTION_ID_HEADER, transactionId);
    if (compressionLevel > 0 && accepts.isGzipAccepted()) {
        if (sendAsFlowFile) {
            post.setHeader(GZIPPED_HEADER, "true");
        } else {
            post.setHeader(CONTENT_ENCODING_HEADER, CONTENT_ENCODING_GZIP_VALUE);
        }
    }
    // Do the actual POST
    final String flowFileDescription = toSend.size() <= 10 ? toSend.toString() : toSend.size() + " FlowFiles";
    final String uploadDataRate;
    final long uploadMillis;
    CloseableHttpResponse response = null;
    try {
        final StopWatch stopWatch = new StopWatch(true);
        response = client.execute(post);
        // consume input stream entirely, ignoring its contents. If we
        // don't do this, the Connection will not be returned to the pool
        EntityUtils.consume(response.getEntity());
        stopWatch.stop();
        uploadDataRate = stopWatch.calculateDataRate(bytesToSend.get());
        uploadMillis = stopWatch.getDuration(TimeUnit.MILLISECONDS);
    } catch (final IOException e) {
        logger.error("Failed to Post {} due to {}; transferring to failure", new Object[] { flowFileDescription, e });
        context.yield();
        for (FlowFile flowFile : toSend) {
            flowFile = session.penalize(flowFile);
            session.transfer(flowFile, REL_FAILURE);
        }
        return;
    } finally {
        if (response != null) {
            try {
                response.close();
            } catch (final IOException e) {
                getLogger().warn("Failed to close HTTP Response due to {}", new Object[] { e });
            }
        }
    }
    // If we get a 'SEE OTHER' status code and an HTTP header that indicates that the intent
    // of the Location URI is a flowfile hold, we will store this holdUri. This prevents us
    // from posting to some other webservice and then attempting to delete some resource to which
    // we are redirected
    final int responseCode = response.getStatusLine().getStatusCode();
    final String responseReason = response.getStatusLine().getReasonPhrase();
    String holdUri = null;
    if (responseCode == HttpServletResponse.SC_SEE_OTHER) {
        final Header locationUriHeader = response.getFirstHeader(LOCATION_URI_INTENT_NAME);
        if (locationUriHeader != null) {
            if (LOCATION_URI_INTENT_VALUE.equals(locationUriHeader.getValue())) {
                final Header holdUriHeader = response.getFirstHeader(LOCATION_HEADER_NAME);
                if (holdUriHeader != null) {
                    holdUri = holdUriHeader.getValue();
                }
            }
        }
        if (holdUri == null) {
            for (FlowFile flowFile : toSend) {
                flowFile = session.penalize(flowFile);
                logger.error("Failed to Post {} to {}: sent content and received status code {}:{} but no Hold URI", new Object[] { flowFile, url, responseCode, responseReason });
                session.transfer(flowFile, REL_FAILURE);
            }
            return;
        }
    }
    if (holdUri == null) {
        if (responseCode == HttpServletResponse.SC_SERVICE_UNAVAILABLE) {
            for (FlowFile flowFile : toSend) {
                flowFile = session.penalize(flowFile);
                logger.error("Failed to Post {} to {}: response code was {}:{}; will yield processing, " + "since the destination is temporarily unavailable", new Object[] { flowFile, url, responseCode, responseReason });
                session.transfer(flowFile, REL_FAILURE);
            }
            context.yield();
            return;
        }
        if (responseCode >= 300) {
            for (FlowFile flowFile : toSend) {
                flowFile = session.penalize(flowFile);
                logger.error("Failed to Post {} to {}: response code was {}:{}", new Object[] { flowFile, url, responseCode, responseReason });
                session.transfer(flowFile, REL_FAILURE);
            }
            return;
        }
        logger.info("Successfully Posted {} to {} in {} at a rate of {}", new Object[] { flowFileDescription, url, FormatUtils.formatMinutesSeconds(uploadMillis, TimeUnit.MILLISECONDS), uploadDataRate });
        for (final FlowFile flowFile : toSend) {
            session.getProvenanceReporter().send(flowFile, url, "Remote DN=" + dnHolder.get(), uploadMillis, true);
            session.transfer(flowFile, REL_SUCCESS);
        }
        return;
    }
    // 
    // the response indicated a Hold URI; delete the Hold.
    // 
    // determine the full URI of the Flow File's Hold; Unfortunately, the responses that are returned have
    // changed over the past, so we have to take into account a few different possibilities.
    String fullHoldUri = holdUri;
    if (holdUri.startsWith("/contentListener")) {
        // If the Hold URI that we get starts with /contentListener, it may not really be /contentListener,
        // as this really indicates that it should be whatever we posted to -- if posting directly to the
        // ListenHTTP component, it will be /contentListener, but if posting to a proxy/load balancer, we may
        // be posting to some other URL.
        fullHoldUri = url + holdUri.substring(16);
    } else if (holdUri.startsWith("/")) {
        // URL indicates the full path but not hostname or port; use the same hostname & port that we posted
        // to but use the full path indicated by the response.
        int firstSlash = url.indexOf("/", 8);
        if (firstSlash < 0) {
            firstSlash = url.length();
        }
        final String beforeSlash = url.substring(0, firstSlash);
        fullHoldUri = beforeSlash + holdUri;
    } else if (!holdUri.startsWith("http")) {
        // Absolute URL
        fullHoldUri = url + (url.endsWith("/") ? "" : "/") + holdUri;
    }
    final HttpDelete delete = new HttpDelete(fullHoldUri);
    delete.setHeader(TRANSACTION_ID_HEADER, transactionId);
    while (true) {
        try {
            final HttpResponse holdResponse = client.execute(delete);
            EntityUtils.consume(holdResponse.getEntity());
            final int holdStatusCode = holdResponse.getStatusLine().getStatusCode();
            final String holdReason = holdResponse.getStatusLine().getReasonPhrase();
            if (holdStatusCode >= 300) {
                logger.error("Failed to delete Hold that destination placed on {}: got response code {}:{}; routing to failure", new Object[] { flowFileDescription, holdStatusCode, holdReason });
                for (FlowFile flowFile : toSend) {
                    flowFile = session.penalize(flowFile);
                    session.transfer(flowFile, REL_FAILURE);
                }
                return;
            }
            logger.info("Successfully Posted {} to {} in {} milliseconds at a rate of {}", new Object[] { flowFileDescription, url, uploadMillis, uploadDataRate });
            for (final FlowFile flowFile : toSend) {
                session.getProvenanceReporter().send(flowFile, url);
                session.transfer(flowFile, REL_SUCCESS);
            }
            return;
        } catch (final IOException e) {
            logger.warn("Failed to delete Hold that destination placed on {} due to {}", new Object[] { flowFileDescription, e });
        }
        if (!isScheduled()) {
            context.yield();
            logger.warn("Failed to delete Hold that destination placed on {}; Processor has been stopped so routing FlowFile(s) to failure", new Object[] { flowFileDescription });
            for (FlowFile flowFile : toSend) {
                flowFile = session.penalize(flowFile);
                session.transfer(flowFile, REL_FAILURE);
            }
            return;
        }
    }
}