fixes https://github.com/TryGhost/Team/issues/1652
fixes https://github.com/TryGhost/Ghost/issues/13319
**Image formatting**
Added support for changing the format of images via the `handle-image-sizes` middleware (e.g. format SVG to png, jpeg, webp)
This change was required:
- Not all browsers support SVG favicons, so we need to convert them to PNGs
- We can't fit image resizing and formatting in the `serve-favicon` middleware: we need to store the resized image to avoid resizing on every request. This system was already present in the `handle-image-sizes` middleware.
To format an uploaded image:
- Original URL: https://localhost/blog/content/images/2022/05/giphy.gif
- To resize: https://localhost/blog/content/images/size/w256h256/2022/05/giphy.gif (already supported)
- To resize and format to webp: https://localhost/blog/content/images/size/w256h256/format/webp/2022/05/giphy.gif
- Animations are preserved when converting Gifs to Webp and in reverse, and also when only resizing (https://github.com/TryGhost/Ghost/issues/13319)
**Favicons**
- Custom favicons are no longer served via `/favicon.png` or `/favicon.ico` (only for default favicon), but use their full path
- Added support for uploading more image extensions in Ghost as a favicon: .jpg, .jpeg, .gif, .webp and .svg are now supported (already supported .png and .ico).
- File extensions other than jpg/jpeg, png, or ico will always get transformed to the image/png format to guarantee browser support (webp and svg images are not yet supported as favicons by all browsers).
For all image formats, other than .ico files:
- Allowed to upload images larger than 1000px in width and height, they will get cropped to 256x256px.
- Allowed uploading favicons that are not square. They will get cropped automatically.
- Allowed to upload larger files, up to 20MB (will get served at a lower file size after being resized)
For .svg files:
- The minimum size of 60x60px is no longer required.
For .ico files:
- The file size limit is increased to 200kb (coming from 100kb)
refs: https://github.com/TryGhost/Team/issues/1633
- this makes /assets/ a more permissible folder - it can serve anything _except_ hbs files
- meanwhile the root folder becomes less permissible, and won't serve theme dev files commonly found in the root
- Currently it's assumed that public files are 100% static
- With card assets, we're using it for files that are partially static, but can change between reboots and theme changes
- We already have a system for managing cache busting across theme changes and restarts - the ?v= key that is added via the asset helper
- This was already in place and used, but servePublicFile's internal cache didn't honor this key, and cached for the lifetime of boot
- This small change means that if a ?v= query param is present on a request for a public file, that we pay attention to it. Else we cache as before
closes: https://github.com/TryGhost/Ghost/issues/13739
- Ghost cannot write to the core folder in correctly configured production installations
- Built assets therefore need to be written to the content directory
- Ghost does not overwrite anything in the content folder as part of an upgrade, therefore static files that are provided by Ghost
must still live inside /core
- So as a result, we now have core/frontend/public and content/public
- If we register the serve public file middleware for a file that doesn't exist, this will currently throw an ENOENT error
- Instead, we want to fall back to a standard 404 so that this behaves normally
- This will be useful for the card asset service, where the cards.min.css and cards.min.js files may or may not exist
- we're slowly trying to draw the lines between the backend and the frontend correctly
- these files deal only with serving the frontend so they should live there
- there are lots of mixed requires in these files, so having them in the right place makes that clear
