passthrough-truncate

node-passthrough-truncate

A PassThrough stream which truncates the last N bytes of a stream.

For example, let's say you are piping a file into a deflate stream, and you want to remove the 0x00 0x00 0xff 0xff at the end. You don't know how long the stream is going to be ahead of time, but you know you need to remove the last 4 bytes.

This module works by keeping enough extra buffers around such that at least N bytes are buffered when the stream is flushed, N being the number of bytes you wish to truncate.

Usage

var PassThroughTruncate = require('passthrough-truncate');
// chop off the last 4 bytes of the stream
myOtherStream.pipe(new PassThroughTruncate(4)).pipe(process.stdout);

API Documentation

new PassThroughStream(truncateByteCount, streamOptions)

• truncateByteCount - number - number of bytes to chop off the end of the stream.
• streamOptions - object - passed directly to the Transform stream constructor.

Returns a PassThrough stream which is missing the last truncateByteCount bytes.

Event: 'error'

function (error) { }

An 'error' event is emitted when the stream contains fewer bytes than truncateByteCount. In this situation, error.code === 'ETOOSMALL'.