How to Download a File (or Image)

kevgski

Was trying to find a way to download an image from a url and use that image as the fill of a layer. Turns out there wasn't much on the topic here so I came up with a little example:

let sketch = require('sketch')
let fiber = require('sketch/async').createFiber()
let doc = sketch.getSelectedDocument()
let selection = doc.selectedLayers.layers[0]

let url = NSURL.URLWithString("https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Sketch_Logo.svg/1024px-Sketch_Logo.svg.png")
let session = NSURLSession.sharedSession()

let block = __mocha__.createBlock_function('v32@?0@"NSURL"8@"NSURLResponse"16@"NSError"24', (url,response,error) => {
    try {
        if (!error) {
          let data = NSData.dataWithContentsOfURL(url) 
          selection.style.fills[0].fillType = 'Pattern'
          selection.style.fills[0].pattern.patternType = 'Fit'
          selection.style.fills[0].pattern.image = data
        } else {
          console.log(error)
        }
    } catch(e) {
      console.log(e)
    }
    fiber.cleanup()
  }
))

let downloadTask = session.downloadTaskWithURL_completionHandler(url,block)
downloadTask.resume()

Couple of notes

Be extra careful with code inside your block. It can be very easy to crash Sketch if any of your code fails. Be sure to wrap in try / catch
Be sure to clean up the fiber when you are done as that can also crash Sketch