README.md

gulp-spawn

Plugin to spawn a CLI program for piping with gulp. Uses spawn.

Usage

gulp-spawn options follow child_process.spawn conventions.

Not all CLI programs support piping. In fact, many newer ones don't. Some programs require that you pass certain arguments if you intend to use stdin and/or stdout. Please check the documentation of the program you intend to use to ensure piping is supported.

The following example pipes image files to ImageMagick's convert. In the case of convert, you must specify a - before arguments and after arguments if you wish to use stdin and stdout, respectively.

var spawn = require("gulp-spawn");

// example using ImageMagick's convert
// setting "buffer: false" optional but recommended for heavy I/O
gulp.src("./src/images/*.{jpg,png,gif}", { buffer: false })
	.pipe(spawn({
		cmd: "convert",
		args: [
			"-",
			"-resize",
			"50%",
			"-"
		],
		// optional
		opts: { cwd: "." },
		filename: function(base, ext) {
			return base + "-half" + ext;
		}
	}))
	.pipe(gulp.dest("./dist/images/"));

The UNIX Pipe Philosophy

If you write spawn programs please consider taking the time to support stdin & stdout. Piping is one of the many reasons UNIX systems have endured the test of time.

Changelog

v0.1.0 - Initial Release v0.2.0 - Added filename callback option v0.2.1 - Fixed support for streams. Effeciency improvements. v0.3.0 - Latest stream support and error emits.