stream-octet-frame

Uses octet counting to frame data through a stream

Data sent using the method frame will be prefixed with the number of bytes in the data. All chunks recieved on the stream will be buffered until the full frame has been recieved, and then it will be emitted as a frame event.

 
var octetFrame = require('stream-octet-frame')
  , net = require('net')
;
 
var server = net.createServer(socket) {
    socket.on('frame', function (buf) {
        console.log('frame recieved: ', buf.toString());
    });
    
    octetFrame(socket, { maxFrameSize: 64 });
    
    socket.frame('write this frame to the socket');
});
 

Installation

npm install stream-octet-frame

Dependencies

none

API

octetFrame(stream, [options])

Adds frame function to stream and listens for octet framed data

options.maxFrameSize (default: 1024)

Maximum number of bytes in each frame

Maximum value is Maximum value is 4294967295 (Math.pow(2, 32) - 1, 4gb - 1byte)

This may also be set on the stream:

stream.maxFrameSize = 1024;

options.readable (default: true)

Set to true to buffer data into frames

options.writable (default: true)

Set to true to add a frame method to stream

options.frameEncoding

Readable stream - will call .toString(frameEncoding) on the frame buffer before emitting the frame event

Writable stream - will use as the default encoding when converting a string into a buffer. Specifying an encoding when calling frame will overwrite this value

This may also be set on the stream:

stream.frameEncoding = 'utf8';

stream.frame(data, [encoding])

Converts data to a buffer with encoding, frames the data, and write the frame and data to the stream

data - A string or buffer encoding - Encoding to use when converting data to a buffer. Overrides options.frameEncoding

Only available if stream is writable and options.writable is true

Events (emitted on the stream)

'frame'

Emitted when a full data frame has been received.

Arguments:

• data - A Buffer containing the data frame. If options.frameEncoding is set, a String will be passes with the specified encoding

Limitations

• Do not use stream.setEncoding() when using this to frame data. The encoding will try to convert the raw bytes into strings, mangling the octet count and data byte cound in the process. The stream docs suggest to always use setEncoding when reading the data as strings, but this is just to buffer parts of the data enough to properly encode multi-byte characters. When framing data, all of the data will be buffered and encoding should work as expected.
• The stream will automatically start to be consumed when using this method.