{

stream<tcp_stream> ws(ioc);

{

//[code_websocket_4_1

net::const_buffer b("Hello, world!", 13);

// This sets all outgoing messages to be sent as text.

// Text messages must contain valid utf8, this is checked

// when reading but not when writing.

ws.text(true);

// Write the buffer as text

ws.write(b);

//]

}

{

//[code_websocket_4_2

// This DynamicBuffer will hold the received message

flat_buffer buffer;

// Read a complete message into the buffer's input area

ws.read(buffer);

// Set text mode if the received message was also text,

// otherwise binary mode will be set.

ws.text(ws.got_text());

// Echo the received message back to the peer. If the received

// message was in text mode, the echoed message will also be

// in text mode, otherwise it will be in binary mode.

ws.write(buffer.data());

// Discard all of the bytes stored in the dynamic buffer,

// otherwise the next call to read will append to the existing

// data instead of building a fresh message.

buffer.consume(buffer.size());

//]

}

{

//[code_websocket_4_3

// This DynamicBuffer will hold the received message

multi_buffer buffer;

// Read the next message in pieces

do

{

// Append up to 512 bytes of the message into the buffer

ws.read_some(buffer, 512);

}

while(! ws.is_message_done());

// At this point we have a complete message in the buffer, now echo it

// The echoed message will be sent in binary mode if the received

// message was in binary mode, otherwise we will send in text mode.

ws.binary(ws.got_binary());

// This buffer adaptor allows us to iterate through buffer in pieces

buffers_suffix<multi_buffer::const_buffers_type> cb{buffer.data()};

// Echo the received message in pieces.

// This will cause the message to be broken up into multiple frames.

for(;;)

{

if(buffer_bytes(cb) > 512)

{

// There are more than 512 bytes left to send, just

// send the next 512 bytes. The value `false` informs

// the stream that the message is not complete.

ws.write_some(false, buffers_prefix(512, cb));

// This efficiently discards data from the adaptor by

// simply ignoring it, but does not actually affect the

// underlying dynamic buffer.

cb.consume(512);

}

else

{

// Only 512 bytes or less remain, so write the whole

// thing and inform the stream that this piece represents

// the end of the message by passing `true`.

ws.write_some(true, cb);

break;

}

}

// Discard all of the bytes stored in the dynamic buffer,

// otherwise the next call to read will append to the existing

// data instead of building a fresh message.

buffer.consume(buffer.size());

//]

}

: public boost::beast::unit_test::suite

{

void

run() override

{

BEAST_EXPECT(&snippets);

}