Object Store and Base64 to file conversion logic

#590 (closed) Object store

Incorporate coko/server file server changes

• Additional config variables & env variables to enable the file server
• New File model overwrites existing File model moving forward
• Migration scripts to move existing files in uploads volume to file server
• Refactor changes on both client and server for fetching and uploading files to file server
• Refactor changes fix permissions based on the new file model

Submission

• On uploading the .docx manuscript the xsweet provides us with images in Base64 format which are converted to the original image source and uploaded to the object-store. The variants of the converted file have three sizes original, medium, and small with format saved either as PNG/JPEG. Then the base64 string is replaced with a medium-sized file URL in the manuscript source HTML.

Wax & manuscript

• added migration script to replace base64 in manuscript source HTML to object-store image URLs.
• As the generated file URL by default expires in one day it's refreshed when the manuscript source is fetched from the server.
• On insertion of base64 images from wax get converted to object storage images on manuscript update and URLs are replaced with medium-sized images (interim solution TODO: Wax asset manager).

Pagedjs

• Tested Pagedjs issue pdf download with fileserver based images to identify & verify the inconsistency is caused by base64 images. Test results seem to indicate the inconsistency was caused by the google fonts imports and a different merge request implemented an interim solution.
• Pagedjs now uses original quality images from the object store on download

Misc

• Converted base64 file to webp logic experimented code