chunkify-stream

chunkify-stream is a duplex stream that combines incoming chunks into arrays of chunks. Functions can be used to control how many chunks are combined and how they are combined.

Usage

The package exports a factory method that creates the duplex stream. The following options are supported:

• combine: A callback function to control how the array of chunks is combined. The function will be called like this: combine(chunks), where the chunks is an array of the chunks. By default a function is used that passes the input array through.

• split: A callback function to control when to split the chunks. The function will be called like this: split(current, last, chunks).

  • current is the current chunk, which is not yet part of the chunks.
  • last is the last chunk, which is already part of the chunks.
  • chunks is the array of all collected chunks.

  If the function returns true, chunks will be emitted and current goes into the next collection of chunks. By default a function is used that always returns false, so all chunks are combined into one big array.

Example

const chunkify = require('chunkify-stream')
 
const alphabeticWordList = chunkify({
  // combine all chunks to a comma separated string
  combine: chunks => chunks.join(', '),
  // split if the first character of the chunks is different
  split: (current, last) => current.slice(0, 1) !== last.slice(0, 1)
})
 
// write the output to the console
alphabeticWordList.on('data', chunk => console.log(chunk))
 
// feed the stream with alphabetic sorted animal names
alphabeticWordList.write('ant')
alphabeticWordList.write('ape')
alphabeticWordList.write('bat')
alphabeticWordList.write('bee')
alphabeticWordList.end()