Previously we only allowed one image optimization per machine, this meant there
was cross talk between avatar resizing and Sidekiq. This could lead to large
amounts of starvation when optimized image version changed which in turn could
block the Sidekiq queue.
This increases amount of allowed load on machines but this is preferable to
having crosstalk between avatar resizing and Sidekiq.
Previously we had no idea what algorithm generated thumbnails, this starts tracking the version.
We also bumped up the version to force all optimized images to be generated. This is important cause we recently introduced pngquant which results in much smaller images.
This feature ensures optimized images run via pngquant, this results extreme amounts of savings for resized images. Effectively the only impact is that the color palette on small resized images is reduced to 256.
To ensure safety we only apply this optimisation to images smaller than 500k.
This commit also makes a bunch of image specs less fragile.
This generates a 10x10 PNG thumbnail for each lightboxed image.
If Image Lazy Loading is enabled (IntersectionObserver API) then
we'll load the low res version when offscreen. As the image scrolls
in we'll swap it for the high res version.
We use a WeakMap to track the old image attributes. It's much less
memory than storing them as `data-*` attributes and swapping them
back and forth all the time.
We regressed and optimized images no longer worked with svg
The following adds the correct logic to simply copy file for svgs
and bypasses resizing for svg avatars
If we detect redis is in readonly we can not correctly get a mutex
raise an exception to notify caller
When getting optimized images avoid the distributed mutex unless
for some reason it is the first call and we need to generate a thumb
In redis readonly no thumbnails will be generated
Previously we used width and height for thumbnails, new code ensures
1. We auto correct width and height
2. We added extra columns for thumbnail_width and height, this is determined
by actual upload and no longer passed in as a side effect
3. Optimized Image now stores filesize which can be used for analysis, decisions
Also
- fixes Android image manifest as a side effect
- fixes issue where a thumbnail generated that is smaller than the upload is no longer used
In the past the filename of the origin was used as the source
for the extension of the file when optimizing on upload.
We now use the actual calculated extension based on upload data.
* `rescue nil` is a really bad pattern to use in our code base.
We should rescue errors that we expect the code to throw and
not rescue everything because we're unsure of what errors the
code would throw. This would reduce the amount of pain we face
when debugging why something isn't working as expexted. I've
been bitten countless of times by errors being swallowed as a
result during debugging sessions.