Chromium rendering under the hood

Knowledge Drop

Last tested: Feb 13, 2019

  1. Run all queries for the dashboard and cache them
  2. Take the dash/look URL we're supposed to render and prepend/append some URL changes and parameters to open the page in presentation mode and to hide some UI elements
  3. Open that URL in headless chromium, wait for it to finish loading
  4. Run some JS on that page which resizes the invisible "viewport" to get the vis at the right size and includes a call to `captureScreenshot` which is a method provided by Chrome Devtools Protocol
  5. Take that image data, send it over to the looker codebase, convert it to the proper image format and deliver (there's a lot more complexity there but that's the gist of it)

     

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Version history
Last update:
‎06-14-2021 06:18 PM
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