Cloudflare Developers•8mo ago

Workers: watermark images hosted on Cloudflare Images

We're trying to apply a watermark with a simple worker script. Code is taken from documentation. It seems that worker's fetch method completely ignores cf.image options. It just returns original image without any modification. It seems a lot of people have this problem. Is it even possible to apply a watermark to an image hosted on Cloudflare Images? Without this feature we would have to store twice the amount of images, and it's a no-go for us. Worker code for reference:

const CLOUDFLARE_IMAGES_PATH = 'https://imagedelivery.net/0lmOObetrqINsoEQE6c8AQ'
const WATERMARK = {
  bottom: 5,
  left: 5,
  opacity: 0.8,
  url: 'https://imagedelivery.net/0lmOObetrqINsoEQE6c8AQ/c544da56-c5cd-47d1-4207-9d3af0451900/origin',
}

addEventListener("fetch", event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  const url = new URL(request.url)
  const image = url.searchParams.get("image")
  if (!image) return new Response('Missing "image" value', { status: 400 })
  if (image.startsWith('http')) return new Response('Provide imageId/variant in "image" value', { status: 400 })
  if (!/(origin|thumb|list|x0grid|x1grid|x2grid)$/.test(image)) {
    return new Response('Disallowed variant name', { status: 400 })
  }

  const imageURL = [CLOUDFLARE_IMAGES_PATH, image].join('/')
  
  return fetch(imageURL, {
    cf: { 
      image: {
        draw: [WATERMARK],
      }
    }
  })
}

const CLOUDFLARE_IMAGES_PATH = 'https://imagedelivery.net/0lmOObetrqINsoEQE6c8AQ'
const WATERMARK = {
  bottom: 5,
  left: 5,
  opacity: 0.8,
  url: 'https://imagedelivery.net/0lmOObetrqINsoEQE6c8AQ/c544da56-c5cd-47d1-4207-9d3af0451900/origin',
}

addEventListener("fetch", event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  const url = new URL(request.url)
  const image = url.searchParams.get("image")
  if (!image) return new Response('Missing "image" value', { status: 400 })
  if (image.startsWith('http')) return new Response('Provide imageId/variant in "image" value', { status: 400 })
  if (!/(origin|thumb|list|x0grid|x1grid|x2grid)$/.test(image)) {
    return new Response('Disallowed variant name', { status: 400 })
  }

  const imageURL = [CLOUDFLARE_IMAGES_PATH, image].join('/')
  
  return fetch(imageURL, {
    cf: { 
      image: {
        draw: [WATERMARK],
      }
    }
  })
}

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Workers: watermark images hosted on Cloudflare Images