API

• Draw a page to the canvas.

  rasterizeHTML.drawURL( url [, canvas] [, options] [, callback] )

• Draw a HTML string to the canvas.

  rasterizeHTML.drawHTML( html [, canvas] [, options] [, callback] )

• Draw a Document to the canvas.

  rasterizeHTML.drawDocument( document [, canvas] [, options] [, callback] )

Parameters:

• url a URL, or
• html a string of HTML, or
• document a Document object.

Optional parameters:

• canvas a HTML5 canvas node
• options key/value pairs of further options
  • width the width of the rendered image, by default the width of the canvas, or '300' if not provided
  • height the height of the rendered image, by default the height of the canvas, or '200' if not provided
  • baseUrl the URL base of the HTML document which relative resources will be based on.
  • executeJs if set to true, it will execute JavaScript in the page/HTML string and wait for the onload event before drawing the content (not available for drawDocument)
  • cache if set to false, it will force requested pages not to be cached by the browser by adding a unique query string in the form of "?_=[timestamp]" to each request.
• callback(image, failedResources) callback function, called when the HTML has been rendered.
  • image the rendered image
  • failedResources a list of resources that failed to load. See below.

Failed resources list

The list of failed resources is returned in the following form: { resourceType: "TYPE_OF_RESOURCE", url: "THE_FAILED_URL", msg: "A_HUMAN_READABLE_MSG" }

Resource types:

• image an <img href="">
• stylesheet a <link rel="stylesheet" href="">
• backgroundImage a background-image: url("");
• fontFace a @font-face { src: url("") }
• script a <script src="">
• scriptExecution a script execution error message (no url specified)
• document a Document object (general error when the whole Document failed to render, no url specified)
• page a HTML page (passed to rasterizeHTML.drawURL())

Stability

rasterizeHTML.js is still in early development and as such might be subject to API changes.

The library exposes some further methods whose interfaces will not be guaranteed to be stable over time.