gm/index.js

// gm - Copyright Aaron Heckmann <aaron.heckmann+github@gmail.com> (MIT Licensed)

/**
 * Module dependencies.
 */

var Stream = require('stream').Stream;
var EventEmitter = require('events').EventEmitter;

/**
 * Constructor.
 *
 * @param {String|Number} path - path to img source or ReadableStream or width of img to create
 * @param {Number} [height] - optional filename of ReadableStream or height of img to create
 * @param {String} [color] - optional hex background color of created img
 */

function gm (source, height, color) {
  var width;

  if (!(this instanceof gm)) {
    return new gm(source, height, color);
  }

  EventEmitter.call(this);

  this._options = {};
  this.options(this.__proto__._options);

  this.data = {};
  this._in = [];
  this._out = [];
  this._outputFormat = null;
  this._subCommand = 'convert';

  if (source instanceof Stream) {
    this.sourceStream = source;
    source = height || 'unknown.jpg';
  } else if (height) {
    // new images
    width = source;
    source = "";

    this.in("-size", width + "x" + height);

    if (color) {
      this.in("xc:"+ color);
    }
  }

  if (typeof source === "string") {
    // then source is a path

    // parse out gif frame brackets from filename
    // since stream doesn't use source path
    // eg. "filename.gif[0]"
    var frames = source.match(/(\[.+\])$/);
    if (frames) {
      this.sourceFrames = source.substr(frames.index, frames[0].length);
      source = source.substr(0, frames.index);
    }
  }

  this.source = source;

  this.addSrcFormatter(function (src) {
    // must be first source formatter
    var inputFromStdin = this.sourceStream || Buffer.isBuffer(this.source);

    var ret = inputFromStdin ? '-' : this.source;
    if (ret && this.sourceFrames) ret += this.sourceFrames;
    src.length = 0;
    src[0] = ret;
  });
}

/**
 * Mixin EventEmitter
 */

for (var method in EventEmitter.prototype) {
  gm.prototype[method] = EventEmitter.prototype[method];
}

var parent = gm;
gm.subClass = function subClass (options) {
  function gm (source, height, color) {
    if (!(this instanceof parent)) {
      return new gm(source, height, color);
    }

    parent.call(this, source, height, color);
  }

  gm.prototype.__proto__ = parent.prototype;
  gm.prototype._options = {};
  gm.prototype.options(options);

  return gm;
}

/**
 * Augment the prototype.
 */

require("./lib/options")(gm.prototype);
require("./lib/getters")(gm);
require("./lib/args")(gm.prototype);
require("./lib/drawing")(gm.prototype);
require("./lib/convenience")(gm.prototype);
require("./lib/command")(gm.prototype);

/**
 * Expose.
 */

module.exports = exports = gm;
module.exports.utils = require('./lib/utils');
module.exports.version = JSON.parse(
  require('fs').readFileSync(__dirname + '/package.json', 'utf8')
).version;