Example usage for io.netty.buffer ByteBuf readableBytes

List of usage examples for io.netty.buffer ByteBuf readableBytes

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Introduction

In this page you can find the example usage for io.netty.buffer ByteBuf readableBytes.

Prototype

public abstract int readableBytes();

Source Link

Document

Returns the number of readable bytes which is equal to (this.writerIndex - this.readerIndex) .

Usage

From source file:com.chiorichan.http.HttpHandler.java

License:Mozilla Public License

/**
 * Handles the HTTP request. Each HTTP subsystem will be explicitly activated until a resolve is determined.
 *
 * @throws IOException/*from  www. j a va2s. c o m*/
 *              Universal exception for all Input/Output errors
 * @throws HttpError
 *              for HTTP Errors
 * @throws PermissionException
 *              for permission problems, like access denied
 * @throws MultipleException
 *              for multiple Scripting Factory Evaluation Exceptions
 * @throws ScriptingException
 *              for Scripting Factory Evaluation Exception
 * @throws SessionException
 *              for problems initializing a new or used session
 */
private void handleHttp() throws Exception // IOException, HttpError, SiteException, PermissionException, MultipleException, ScriptingException, SessionException
{
    log.log(Level.INFO, request.methodString() + " " + request.getFullUrl());

    Session sess = request.startSession();

    log.log(Level.FINE, "Session {id=%s,timeout=%s,new=%s}", sess.getSessId(), sess.getTimeout(), sess.isNew());

    if (response.getStage() == HttpResponseStage.CLOSED)
        throw new IOException("Connection reset by peer"); // This is not the only place 'Connection reset by peer' is thrown

    RequestEvent requestEvent = new RequestEvent(request);

    try {
        EventBus.instance().callEventWithException(requestEvent);
    } catch (EventException ex) {
        throw new IOException(
                "Exception encountered during request event call, most likely the fault of a plugin.", ex);
    }

    response.setStatus(requestEvent.getStatus());

    if (requestEvent.isCancelled()) {
        int status = requestEvent.getStatus();
        String reason = requestEvent.getReason();

        if (status == 200) {
            status = 502;
            reason = "Navigation Cancelled by Plugin Event";
        }

        NetworkManager.getLogger().warning("Navigation was cancelled by a Plugin Event");

        throw new HttpError(status, reason);
    }

    if (response.isCommitted())
        return;

    // Throws IOException and HttpError
    fi = new WebInterpreter(request);
    response.annotations.putAll(fi.getAnnotations());

    currentSite = request.getLocation();
    sess.setSite(currentSite);

    if (request.getSubdomain().length() > 0
            && !currentSite.getSubdomain(request.getSubdomain()).isMaped(request.getDomain())) {
        if ("www".equalsIgnoreCase(request.getSubdomain())
                || AppConfig.get().getBoolean("sites.redirectMissingSubDomains")) {
            log.log(Level.SEVERE, "Redirecting non-existent subdomain '%s' to root domain '%s'",
                    request.getSubdomain(), request.getFullUrl(""));
            response.sendRedirect(request.getFullUrl(""));
        } else {
            log.log(Level.SEVERE, "The requested subdomain '%s' is non-existent.", request.getSubdomain(),
                    request.getFullDomain(""));
            response.sendError(HttpResponseStatus.NOT_FOUND, "Subdomain not found");
        }
        return;
    }

    File docRoot = currentSite.getSubdomain(request.getSubdomain()).directory();

    Validate.notNull(docRoot);

    if (sess.isLoginPresent())
        log.log(Level.FINE, "Account {id=%s,displayName=%s}", sess.getId(), sess.getDisplayName());

    /*
     * Start: SSL enforcer
     *
     * Acts on the value of annotation 'SSL'.
     * REQUIRED means a forbidden error will be thrown is it can not be accomplished
     *
     * Options include:
     * Preferred: If SSL is available, we preferred to be switched to it
     * PostOnly: SSL is REQUIRED is this is a POST request
     * GetOnly: SSL is REQUIRED if this is a GET request
     * Required: SSL is REQUIRED, no exceptions!
     * Deny: SSL is DENIED, no exceptions!
     * Ignore: We don't care one way or other, do nothing! DEFAULT
     */
    SslLevel sslLevel = SslLevel.parse(fi.get("ssl"));
    boolean required = false;

    switch (sslLevel) {
    case Preferred:
        if (NetworkManager.isHttpsRunning())
            required = true;
        break;
    case PostOnly:
        if (request.method() == HttpMethod.POST)
            required = true;
        break;
    case GetOnly:
        if (request.method() == HttpMethod.GET)
            required = true;
        break;
    case Required:
        required = true;
        break;
    case Deny:
        if (ssl) {
            if (!response.switchToUnsecure())
                response.sendError(HttpCode.HTTP_FORBIDDEN, "This page requires an unsecure connection.");
            return;
        }
        break;
    case Ignore:
        break;
    }

    if (required && !ssl) {
        if (!response.switchToSecure())
            response.sendError(HttpCode.HTTP_FORBIDDEN, "This page requires a secure connection.");
        return;
    }
    /*
     * End: SSL enforcer
     */

    if (fi.getStatus() != HttpResponseStatus.OK)
        throw new HttpError(fi.getStatus());

    /*
     * Start: Apache Configuration Section
     *
     * Loads a Apache configuration and .htaccess files into a common handler, then parsed for directives like access restrictions and basic auth
     * TODO Load server-wide Apache Configuration then merge with Site Configuration
     */
    ApacheHandler htaccess = new ApacheHandler();
    response.setApacheParser(htaccess);

    try {
        boolean result = htaccess.handleDirectives(currentSite.getApacheConfig(), this);

        if (htaccess.overrideNone() || htaccess.overrideListNone()) // Ignore .htaccess files
        {
            if (fi.hasFile())
                if (!htaccess.handleDirectives(new ApacheConfiguration(fi.getFile().getParentFile()), this))
                    result = false;

            if (!htaccess.handleDirectives(new ApacheConfiguration(docRoot), this))
                result = false;
        }

        if (!result) {
            if (!response.isCommitted())
                response.sendError(500,
                        "Your request was blocked by an internal configuration directive, exact details are unknown.");
            return;
        }
    } catch (ApacheDirectiveException e) {
        log.log(Level.SEVERE, "Caught Apache directive exception: " + e.getMessage());

        // TODO Throw 500 unless told not to
    }
    /*
     * End: Apache Configuration Section
     */

    if (!fi.hasFile() && !fi.hasHTML())
        response.setStatus(HttpResponseStatus.NO_CONTENT);

    sess.setGlobal("__FILE__", fi.getFile());

    request.putRewriteParams(fi.getRewriteParams());
    response.setContentType(fi.getContentType());
    response.setEncoding(fi.getEncoding());

    request.getServer().put(ServerVars.DOCUMENT_ROOT, docRoot);

    request.setGlobal("_SERVER", request.getServer());
    request.setGlobal("_POST", request.getPostMap());
    request.setGlobal("_GET", request.getGetMap());
    request.setGlobal("_REWRITE", request.getRewriteMap());
    request.setGlobal("_FILES", request.getUploadedFiles());

    // TODO Implement NONCE requirement for login page
    NonceLevel level = NonceLevel.parse(fi.get("nonce"));
    boolean nonceProvided = sess.nonce() == null ? false
            : request.getRequestMap().get(sess.nonce().key()) != null;
    boolean processNonce = false;

    switch (level) {
    case Required:
        processNonce = true;
        break;
    case GetOnly:
        processNonce = request.method() == HttpMethod.GET || nonceProvided;
        break;
    case PostOnly:
        processNonce = request.method() == HttpMethod.POST || nonceProvided;
        break;
    case Flexible:
        processNonce = nonceProvided;
        break;
    case Disabled:
    default:
        // Do Nothing
    }

    Map<String, String> nonceMap = Maps.newHashMap();

    if (processNonce) {
        if (!nonceProvided) {
            log.log(Level.SEVERE,
                    "The request has failed NONCE validation, because the nonce key was not present!");
            response.sendError(HttpResponseStatus.FORBIDDEN, "Your request has failed NONCE validation!");
            return;
        }

        Nonce nonce = sess.nonce();

        if (level == NonceLevel.Required)
            // Required NonceLevels are of the highest protected state
            sess.destroyNonce();

        try {
            if (!(request.getRequestMap().get(nonce.key()) instanceof String))
                throw new NonceException("Nonce token is not a string");
            nonce.validateWithException((String) request.getRequestMap().get(nonce.key()));
        } catch (NonceException e) {
            log.log(Level.SEVERE,
                    "The request has failed NONCE validation, because " + e.getMessage().toLowerCase() + "!");
            response.sendError(HttpResponseStatus.FORBIDDEN, "Your request has failed NONCE validation!");
            sess.destroyNonce();
            return;
        } finally {
            log.log(Level.INFO, "The request has passed the NONCE validation!");
            request.nonceProcessed(true);
            nonceMap = nonce.mapValues();
        }
    }

    if (request.validateLogins())
        return;

    if (level != NonceLevel.Disabled)
        request.setGlobal("_NONCE", nonceMap);

    try {
        if (request.getUploadedFiles().size() > 0)
            log.log(Level.INFO,
                    "Uploads {"
                            + StringFunc.limitLength(
                                    Joiner.on(",").skipNulls().join(request.getUploadedFiles().values()), 255)
                            + "}");

        if (request.getGetMap().size() > 0)
            log.log(Level.INFO, "Params GET {" + StringFunc.limitLength(
                    Joiner.on(",").withKeyValueSeparator("=").useForNull("null").join(request.getGetMap()), 255)
                    + "}");

        if (request.getPostMap().size() > 0)
            log.log(Level.INFO, "Params POST {" + StringFunc.limitLength(
                    Joiner.on(",").withKeyValueSeparator("=").useForNull("null").join(request.getPostMap()),
                    255) + "}");

        if (request.getRewriteMap().size() > 0)
            log.log(Level.INFO, "Params REWRITE {" + StringFunc.limitLength(
                    Joiner.on(",").withKeyValueSeparator("=").useForNull("null").join(request.getRewriteMap()),
                    255) + "}");

        if (fi.getAnnotations().size() > 0)
            log.log(Level.INFO, "Params ANNOTATIONS {" + StringFunc.limitLength(
                    Joiner.on(",").withKeyValueSeparator("=").useForNull("null").join(fi.getAnnotations()), 255)
                    + "}");
    } catch (Throwable t) {
        t.printStackTrace();
    }

    if (AppConfig.get().getBoolean("advanced.security.requestMapEnabled", true))
        request.setGlobal("_REQUEST", request.getRequestMap());

    ByteBuf rendered = Unpooled.buffer();

    ScriptingFactory factory = request.getEvalFactory();
    factory.setEncoding(fi.getEncoding());

    NetworkSecurity.isForbidden(htaccess, currentSite, fi);

    String req = fi.get("reqperm");

    if (req == null)
        req = "-1";

    sess.requirePermission(req, currentSite.getId());

    // Enhancement: Allow HTML to be ran under different shells. Default is embedded.
    if (fi.hasHTML()) {
        ScriptingResult result = factory.eval(
                ScriptingContext.fromSource(fi.getHTML(), "<embedded>").request(request).site(currentSite));

        if (result.hasExceptions())
            // TODO Print notices to output like PHP does
            for (ScriptingException e : result.getExceptions()) {
                ExceptionReport.throwExceptions(e);
                log.exceptions(e);
                if (e.reportingLevel().isEnabled())
                    rendered.writeBytes(e.getMessage().getBytes());
            }

        if (result.isSuccessful()) {
            rendered.writeBytes(result.content());
            if (result.getObject() != null && !(result.getObject() instanceof NullObject))
                try {
                    rendered.writeBytes(ObjectFunc.castToStringWithException(result.getObject()).getBytes());
                } catch (Exception e) {
                    log.log(Level.SEVERE, "Exception Excountered: %s", e.getMessage());
                    if (Versioning.isDevelopment())
                        log.log(Level.SEVERE, e.getStackTrace()[0].toString());
                }
        }

        log.log(Level.INFO, "EvalHtml {timing=%sms,success=%s}", Timings.mark(this), result.isSuccessful());
    }

    if (fi.hasFile()) {
        if (fi.isDirectoryRequest()) {
            processDirectoryListing();
            return;
        }

        ScriptingResult result = factory.eval(ScriptingContext.fromFile(fi).request(request).site(currentSite));

        if (result.hasExceptions())
            // TODO Print notices to output like PHP does
            for (ScriptingException e : result.getExceptions()) {
                ExceptionReport.throwExceptions(e);
                log.exceptions(e);
                if (e.reportingLevel().isEnabled() && e.getMessage() != null)
                    rendered.writeBytes(e.getMessage().getBytes());
            }

        if (result.isSuccessful()) {
            rendered.writeBytes(result.content());
            if (result.getObject() != null && !(result.getObject() instanceof NullObject))
                try {
                    rendered.writeBytes(ObjectFunc.castToStringWithException(result.getObject()).getBytes());
                } catch (Exception e) {
                    rendered.writeBytes(result.getObject().toString().getBytes());
                    log.log(Level.SEVERE, "Exception encountered while writing returned object to output. %s",
                            e.getMessage());
                    if (Versioning.isDevelopment())
                        log.log(Level.SEVERE, e.getStackTrace()[0].toString());
                }
        }

        log.log(Level.INFO, "EvalFile {file=%s,timing=%sms,success=%s}", fi.getFilePath(), Timings.mark(this),
                result.isSuccessful());
    }

    // if the connection was in a MultiPart mode, wait for the mode to change then return gracefully.
    if (response.stage == HttpResponseStage.MULTIPART) {
        while (response.stage == HttpResponseStage.MULTIPART)
            // I wonder if there is a better way to handle multipart responses.
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                throw new HttpError(500, "Internal Server Error encountered during multipart execution.");
            }

        return;
    }
    // If the connection was closed from page redirect, return gracefully.
    else if (response.stage == HttpResponseStage.CLOSED || response.stage == HttpResponseStage.WRITTEN)
        return;

    // Allows scripts to directly override interpreter values. For example: Themes, Views, Titles
    for (Entry<String, String> kv : response.annotations.entrySet())
        fi.put(kv.getKey(), kv.getValue());

    RenderEvent renderEvent = new RenderEvent(this, rendered, fi.getEncoding(), fi.getAnnotations());

    try {
        EventBus.instance().callEventWithException(renderEvent);
        if (renderEvent.getSource() != null)
            rendered = renderEvent.getSource();
    } catch (EventException ex) {
        throw new ScriptingException(ReportingLevel.E_ERROR,
                "Caught EventException while trying to fire the RenderEvent", ex.getCause());
    }

    log.log(Level.INFO, "Written {bytes=%s,total_timing=%sms}", rendered.readableBytes(), Timings.finish(this));

    try {
        response.write(rendered);
    } catch (IllegalReferenceCountException e) {
        log.log(Level.SEVERE, "Exception encountered while writting script object to output, %s",
                e.getMessage());
    }
}

From source file:com.chiorichan.http.ssl.SniNegotiator.java

License:Mozilla Public License

@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
    if (!handshaken && in.readableBytes() >= 5) {
        String hostname = sniHostNameFromHandshakeInfo(in);
        if (hostname != null)
            hostname = IDN.toASCII(hostname, IDN.ALLOW_UNASSIGNED).toLowerCase(Locale.US);
        this.hostname = hostname;

        selectedContext = SslManager.instance().map(hostname);

        if (handshaken) {
            SSLEngine engine = selectedContext.newEngine(ctx.alloc());

            List<String> supportedCipherSuites = Arrays.asList(engine.getSupportedCipherSuites());

            if (!supportedCipherSuites.containsAll(enabledCipherSuites))
                for (String cipher : enabledCipherSuites)
                    if (!supportedCipherSuites.contains(cipher)) {
                        NetworkManager.getLogger()
                                .severe(String.format(
                                        "The SSL/TLS cipher suite '%s' is not supported by SSL Provider %s",
                                        cipher, SslContext.defaultServerProvider().name()));
                        enabledCipherSuites.remove(cipher);
                    }/*from  w  ww  . j a  va  2  s . c om*/

            engine.setUseClientMode(false);
            engine.setEnabledCipherSuites(enabledCipherSuites.toArray(new String[0]));

            ctx.pipeline().replace(this, ctx.name(), new SslExceptionHandler(engine));
        }
    }
}

From source file:com.chiorichan.http.ssl.SniNegotiator.java

License:Mozilla Public License

private String sniHostNameFromHandshakeInfo(ByteBuf in) {
    int readerIndex = in.readerIndex();
    try {/*  w w w  .j a v  a2s  . c o m*/
        int command = in.getUnsignedByte(readerIndex);

        // tls, but not handshake command
        switch (command) {
        case SslConstants.SSL_CONTENT_TYPE_CHANGE_CIPHER_SPEC:
        case SslConstants.SSL_CONTENT_TYPE_ALERT:
        case SslConstants.SSL_CONTENT_TYPE_APPLICATION_DATA:
            return null;
        case SslConstants.SSL_CONTENT_TYPE_HANDSHAKE:
            break;
        default:
            //not tls or sslv3, do not try sni
            handshaken = true;
            return null;
        }

        int majorVersion = in.getUnsignedByte(readerIndex + 1);

        // SSLv3 or TLS
        if (majorVersion == 3) {
            int packetLength = in.getUnsignedShort(readerIndex + 3) + 5;

            if (in.readableBytes() >= packetLength) {
                // decode the ssl client hello packet
                // we have to skip some var-length fields
                int offset = readerIndex + 43;

                int sessionIdLength = in.getUnsignedByte(offset);
                offset += sessionIdLength + 1;

                int cipherSuitesLength = in.getUnsignedShort(offset);
                offset += cipherSuitesLength + 2;

                int compressionMethodLength = in.getUnsignedByte(offset);
                offset += compressionMethodLength + 1;

                int extensionsLength = in.getUnsignedShort(offset);
                offset += 2;
                int extensionsLimit = offset + extensionsLength;

                while (offset < extensionsLimit) {
                    int extensionType = in.getUnsignedShort(offset);
                    offset += 2;

                    int extensionLength = in.getUnsignedShort(offset);
                    offset += 2;

                    // SNI
                    if (extensionType == 0) {
                        handshaken = true;
                        int serverNameType = in.getUnsignedByte(offset + 2);
                        if (serverNameType == 0) {
                            int serverNameLength = in.getUnsignedShort(offset + 3);
                            return in.toString(offset + 5, serverNameLength, CharsetUtil.UTF_8);
                        } else
                            // invalid enum value
                            return null;
                    }

                    offset += extensionLength;
                }

                handshaken = true;
                return null;
            } else
                // client hello incomplete
                return null;
        } else {
            handshaken = true;
            return null;
        }
    } catch (Throwable e) {
        // unexpected encoding, ignore sni and use default
        if (logger.isDebugEnabled())
            logger.debug("Unexpected client hello packet: " + ByteBufUtil.hexDump(in), e);
        handshaken = true;
        return null;
    }
}

From source file:com.chiorichan.util.ServerFunc.java

License:Mozilla Public License

public static byte[] byteBuf2Bytes(ByteBuf buf) {
    byte[] bytes = new byte[buf.readableBytes()];
    int readerIndex = buf.readerIndex();
    buf.getBytes(readerIndex, bytes);//from  www .j a  va  2s .  c o  m
    return bytes;
}

From source file:com.chuck.netty4.websocket.WebSocketIndexPageHandler.java

License:Apache License

@Override
protected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest req) throws Exception {
    // Handle a bad request.
    if (!req.decoderResult().isSuccess()) {
        sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST));
        return;/*  w w w . j  av  a2  s  .  co m*/
    }

    // Allow only GET methods.
    if (req.method() != GET) {
        sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN));
        return;
    }

    // Send the index page
    if ("/".equals(req.uri()) || "/index.html".equals(req.uri())) {
        String webSocketLocation = getWebSocketLocation(ctx.pipeline(), req, websocketPath);
        ByteBuf content = WebSocketServerIndexPage.getContent(webSocketLocation);
        FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content);

        res.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/html; charset=UTF-8");
        HttpUtil.setContentLength(res, content.readableBytes());

        sendHttpResponse(ctx, req, res);
    } else {
        sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND));
    }
}

From source file:com.cloudera.livy.client.local.rpc.KryoMessageCodec.java

License:Apache License

@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
    if (in.readableBytes() < 4) {
        return;//from   w ww . jav a 2  s  .  com
    }

    in.markReaderIndex();
    int msgSize = in.readInt();
    checkSize(msgSize);

    if (in.readableBytes() < msgSize) {
        // Incomplete message in buffer.
        in.resetReaderIndex();
        return;
    }

    try {
        ByteBuffer nioBuffer = maybeDecrypt(in.nioBuffer(in.readerIndex(), msgSize));
        Object msg = serializer.deserialize(nioBuffer);
        LOG.debug("Decoded message of type {} ({} bytes)", msg != null ? msg.getClass().getName() : msg,
                msgSize);
        out.add(msg);
    } finally {
        in.skipBytes(msgSize);
    }
}

From source file:com.cloudhopper.smpp.pdu.BaseBind.java

License:Apache License

@Override
public void readBody(ByteBuf buffer) throws UnrecoverablePduException, RecoverablePduException {
    this.systemId = ChannelBufferUtil.readNullTerminatedString(buffer);
    this.password = ChannelBufferUtil.readNullTerminatedString(buffer);
    this.systemType = ChannelBufferUtil.readNullTerminatedString(buffer);
    // at this point, we should have at least 3 bytes left
    if (buffer.readableBytes() < 3) {
        throw new NotEnoughDataInBufferException("After parsing systemId, password, and systemType",
                buffer.readableBytes(), 3);
    }/* w w w. jav a2 s .  c o m*/
    this.interfaceVersion = buffer.readByte();
    this.addressRange = ChannelBufferUtil.readAddress(buffer);
}

From source file:com.cloudhopper.smpp.pdu.BufferHelper.java

License:Apache License

static public byte[] createByteArray(ByteBuf buffer) throws Exception {
    byte[] bytes = new byte[buffer.readableBytes()];
    // temporarily read bytes from the buffer
    buffer.getBytes(buffer.readerIndex(), bytes);
    return bytes;
}

From source file:com.cloudhopper.smpp.pdu.Pdu.java

License:Apache License

public void readOptionalParameters(ByteBuf buffer, PduTranscoderContext context)
        throws UnrecoverablePduException, RecoverablePduException {
    // if there is any data left, it's part of an optional parameter
    while (buffer.readableBytes() > 0) {
        Tlv tlv = ChannelBufferUtil.readTlv(buffer);
        if (tlv.getTagName() == null) {
            tlv.setTagName(context.lookupTlvTagName(tlv.getTag()));
        }//from   w w w  .  j  a v a  2 s  . c o m
        this.addOptionalParameter(tlv);
    }
}

From source file:com.cloudhopper.smpp.simulator.SmppSimulatorSessionHandler.java

License:Apache License

@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf buffer, List<Object> out) throws Exception {
    // ignore requests with zero bytes
    if (buffer.readableBytes() <= 0) {
        return;/*w w w.ja  v  a2 s.  com*/
    }

    // decode the buffer into a pdu
    Pdu pdu = transcoder.decode(buffer);

    // if the pdu was null, we don't have enough data yet
    if (pdu == null) {
        logger.info("Received data on channel {}, but not enough to parse PDU fully yet", channel.toString());
        logger.info("Bytes in buffer: [{}]", ByteBufUtil.hexDump(buffer));
        return;
    }

    logger.info("Decoded buffer on channel {} into PDU: {}", channel.toString(), pdu);

    // if we have a pdu procesor registered, let's see if it handles it
    boolean processed = false;
    if (this.pduProcessor != null) {
        processed = this.pduProcessor.process(this, channel, pdu);
    }

    if (processed) {
        logger.info("This PDU was processed by the registered PduProcessor");
    } else {
        this.pduQueue.add(pdu);
    }

    // is there a PDU someone wants us to write in response?
    if (this.writePduQueue.size() > 0) {
        Pdu pduToWrite = this.writePduQueue.remove();
        logger.info("Automatically writing back on channel {} the PDU: {}", channel.toString(), pduToWrite);
        ByteBuf writeBuffer = this.transcoder.encode(pduToWrite);
        channel.writeAndFlush(writeBuffer);
    }

    out.add(pdu);
}