ByteToStringDecoder Class Reference

Inheritance diagram for ByteToStringDecoder:

Public Member Functions
bool	decode (Context *, IOBufQueue &buf, std::string &result, size_t &) override
Public Member Functions inherited from wangle::ByteToMessageDecoder< std::string >
void	transportActive (Context *ctx) override
void	transportInactive (Context *ctx) override
void	read (Context *ctx, folly::IOBufQueue &q) override
Public Member Functions inherited from wangle::InboundHandler< folly::IOBufQueue &, std::string >
	~InboundHandler () override=default
virtual void	readEOF (Context *ctx)
virtual void	readException (Context *ctx, folly::exception_wrapper e)
Public Member Functions inherited from wangle::HandlerBase< InboundHandlerContext< std::string > >
virtual	~HandlerBase ()=default
virtual void	attachPipeline (InboundHandlerContext< std::string > *)
virtual void	detachPipeline (InboundHandlerContext< std::string > *)
InboundHandlerContext< std::string > *	getContext ()

Additional Inherited Members
Public Types inherited from wangle::ByteToMessageDecoder< std::string >
typedef InboundHandler< folly::IOBufQueue &, std::string >::Context	Context
Public Types inherited from wangle::InboundHandler< folly::IOBufQueue &, std::string >
typedef folly::IOBufQueue &	rin
typedef std::string	rout
typedef folly::Unit	win
typedef folly::Unit	wout
typedef InboundHandlerContext< std::string >	Context
Static Public Attributes inherited from wangle::InboundHandler< folly::IOBufQueue &, std::string >
static const HandlerDir	dir

Detailed Description

Steps to run: 1) Run an upstream server that can broadcast messages:

nc -l localhost 8081

This starts a server on localhost:8081.

2) Start the broadcast proxy with the upstream_port set to 8081:

./broadcast_proxy –port 8080 –upstream_port 8081

This starts the proxy on localhost:8080 and sets the upstream server as localhost:8081

3) Start a new instances of telnet clients to connect to the broadcast proxy and listen to the messages broadcasted by the upstream server:

telnet localhost 8080

Send some bytes in the telnet terminals for broadcast_proxy to kick off the connection.

4) Type something in the nc terminal and notice that it is broadcasted to all the telnet clients. A simple decoder that decodes bytes in IOBufQueue to std::string. This is used in the BroadcastPipeline to convert bytes read from the upstream server's socket to strings of messages that can be broadcasted to all the clients/observers.

Definition at line 69 of file BroadcastProxy.cpp.

Member Function Documentation

bool ByteToStringDecoder::decode ( Context *  ctx, IOBufQueue &  buf, std::string &  result, size_t &    )

inlineoverridevirtual

Decode bytes from buf into result.

Returns

bool - Return true if decoding is successful, false if buf has insufficient bytes.

Implements wangle::ByteToMessageDecoder< std::string >.

Definition at line 71 of file BroadcastProxy.cpp.

References folly::IOBufQueue::chainLength(), and folly::IOBufQueue::move().

                                {
    if (buf.chainLength() > 0) {
      result = buf.move()->moveToFbString().toStdString();
      return true;
    }
    return false;
  }

---

The documentation for this class was generated from the following file:

• proxygen/wangle/wangle/example/broadcast/BroadcastProxy.cpp