Image upload workflow

• User uploads the image using web interface

• The upload progress is shown on the client side as the chunks of the image are uploaded into gridfs

• After the last chunk is processed

  • A celery task is submitted to deal with newly uploaded imagefile
  • Update the “status” in the metadata of the imagefile in gridfs to “pending”

• When celery worker picks up this task, following sub-tasks are executed in sequence

  • Copy file from gridfs into a temporary location
  • Update the “status” in the metadata of the imagefile in gridfs to “processing”
  • Choose the uploader based on file extention
  • Update the image metadata in imagestore
  • Dice the image to a multiresolution pyramid
  • Create a view in corresponding session
  • Update the “status” in the metadata of the imagefile in gridfs to “ready”
  • Cleanup the temporary download location

• If something goes wrong, the status of imagefile is updated to “failed” with some reason.

• Now when the user sees imagefile item, the user sees either “finish”, or “retry” buttons. At this time a view is also visible in the session.

• Finish button will hide the imagefile entry (or delete ?). The imagefile will now be only accessible through imagestore interface (Not ready)