proc-stream

Get process output as a single stream.

This package splits a process's stdout and stderr into lines and merges them into a single stream, to make it easy to print its output with debug or similar libraries.

Optionally stdout and stderr can be transformed line by line before or after merging.

Installation

npm install proc-stream

Usage

var procStream = require('proc-stream');
 
var proc = spawn('script.sh', []);
 
// basic usage, get stdout and stderr in a single stream
procStream(proc).pipe(process.stdout);
 
// decorate stderr and log with debug()
procStream(proc, {
  // show stderr lines in red
  stderr: function(chunk) {
    return chalk.red(chunk);
  },
  // transform both stdout and stderr
  both: function(chunk) {
    return 'cmd: '+chunk;
  },
  // do not add newlines after each line
  newline: null
}).on('data', function(data) {
  debug(data);
});
 
// decorate stdout, disable stderr and set a custom newline
var stream = procStream(proc, {
  // transform stdout
  stdout: function(chunk) {
    return chalk.green(chunk);
  },
  // disable stderr
  stderr: null,
  // custom newline (default is '\n')
  newline: '\r\n'
}).pipe(process.stdout);

License

MIT license - http://www.opensource.org/licenses/mit-license.php