This class uploads to an S3 bucket. And was adapted from this blog post: http://www.ioncannon.net/programming/1539/direct-browser-uploading-amazon-s3-cors-fileapi-xhr2-and-signed-puts/ You need to have an endpoint on your server that will sign your S3 request for you ('covered in the plog post'). To use: App.S3Upload.create({ file: file-from-fil…

S3Upload.js

App.S3Upload = Ember.Object.extend({
  progress: 0,
	state: "pending",
	bucket: 'your-bucket'
	complete: false,
	s3url: null,
	xhr: null,
	file: null,
	fileName: function() {
		var file = this.get('file');
		return file.name;
	}.property('file'),
	progressStyle: function() {
		return 'width: ' + this.get('progress') + '%';
	}.property('progress'),
	startUpload: function() {
		var model = this;
		var file = this.get('file');
		var jqxhr = $.get('admin/signput?name=' + file.name + '&type=' + file.type + '&bucket=' + this.get('bucket'))
            		.done(function(url) {
            			model.set('s3url', url);
            			model.uploadtoS3();
            		});
	},
	uploadtoS3: function() {
		this.createCORSRequest();
	  	var xhr = this.get('xhr'),
			model = this;

		if (!xhr) {
			model.set('state', 'CORS not supported');
		}
		else {
			xhr.onload = function() {
			  if(xhr.status == 200) {
			    model.set('state', 'Upload Completed');
			  }
			  else {
			    model.set('state', 'Upload error: ' + xhr.status);
			  }
			  model.onComplete();
			};

			xhr.onerror = function() {
				model.set('state', 'XHR Error' + xhr.status);
				model.onComplete();
			};

			xhr.upload.onprogress = function(e) {
				if (e.lengthComputable) {
					var percentLoaded = Math.round((e.loaded / e.total) * 100);
					model.set('progress', percentLoaded);
					model.set('state', percentLoaded == 100 ? 'Finalizing.' : 'Uploading.');
				}
			};

			xhr.setRequestHeader('Content-Type', model.get('file').type);
			xhr.setRequestHeader('x-amz-acl', 'public-read');
			xhr.send(model.get('file'));
		}
	},
	createCORSRequest: function() {
		var xhr = new XMLHttpRequest(),
			url = this.get('s3url');
		if ("withCredentials" in xhr) {
			xhr.open('PUT', url, true);
		} 
		else if (typeof XDomainRequest != "undefined")  {
			xhr = new XDomainRequest();
			xhr.open('PUT', url);
		} 
		else {
			xhr = null;
		}
		this.set('xhr', xhr);
	},
	onComplete: function() {
		this.set('complete', true);
	}
});