Migrating to appimageupdatetool to get delta updates

[Samueru-sama]

Since we already have appimageupdatetool in the repo, all that we need to do is use it if available.

I took a look at the update function in the main script, and it actually doesn't know the name of the applications, all it does is look for AM-updater scripts in APPSPATH.

I think it is simpler to simply insert something that would use appimageupdatetool in AM-updater and then exit, like this:

if command -v appimageupdatetool >/dev/null 2>&1; then
    appimageupdatetool -O -r "/opt/$APP/$APP" && chmod a+x "/opt/$APP/$APP" && exit 0
fi

...rest of the AM-updater...

I did some testing and it seems to work perfectly, some appimages have broken update info in them so I need to make sure that the script doesn't continue to exit 0 when that happens.

EDIT: It works even when the zsync info is broken as appimageupdatetool does indeed not exit with a zero status when that happens, phew!

[ivan-hc]

we can apply the patch the same way we do with the "remove" script, to prevent unprivileged users removing the app

[Samueru-sama]

we can apply the patch the same way we do with the "remove" script, to prevent unprivileged users removing the app

In that case I think it is easier to turn it into a single line, like this:

command -v appimageupdatetool && appimageupdatetool -O -r "/opt/$APP/$APP" && chmod a+x "/opt/$APP/$APP" && exit 0

and insert it between lines 4 and 5 in the typical AM-updater script for appimages.

[Samueru-sama]

I've found something interesting.

I tested adding this to the script, after the [ -n "$version" ] check, since we will have to add $version after the update is done to keep the version file up to date.

if command -v appimageupdatetool >/dev/null 2>&1; then
	cd "/opt/$APP" || exit 1
	appimageupdatetool -Or ./"$APP" && chmod a+x ./"$APP" && echo "$version" > ./version && exit 0
fi

Turns out that when you give relative paths to appimageupdatetool instead of full paths like I was doing before, it deletes the wrong file wtf

Testing it with brave.

~/Local/opt/brave/ ./AM-updater                                                                              2313ms 
Checking for updates...
Fetching release information for tag "stable" from GitHub API.
Fetching release information for tag "stable" from GitHub API.
zsync2: Using CA bundle found on system: /etc/ssl/cert.pem
... done!
Starting update...

Fetching release information for tag "stable" from GitHub API.
0% done
Updating from GitHub Releases via ZSync
Fetching release information for tag "stable" from GitHub API.
zsync2: Using CA bundle found on system: /etc/ssl/cert.pem
0% done
zsync2: /home/samuel/Local/opt/brave/./brave found, using as seed file
zsync2: Target file: /home/samuel/Local/opt/brave/./brave
zsync2: Reading seed file: /home/samuel/Local/opt/brave/./brave
5.27% done (7.79 of 147.71 MiB)...
zsync2: Usable data from seed files: 5.273040%
zsync2: Renaming temp file
zsync2: Fetching remaining blocks
5.27% done (7.79 of 147.71 MiB)...
zsync2: Downloading from https://objects.githubusercontent.com/github-production-release-asset-2e65be/321930328/f2885778-c984-4c24-80e0-89115ad655b2?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=releaseassetproduction%2F20240818%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240818T105710Z&X-Amz-Expires=300&X-Amz-Signature=aa9118e2a5faa04592467fe821434abaeecdf85fa38e013de1490dcd0acb85cb&X-Amz-SignedHeaders=host&actor_id=0&key_id=0&repo_id=321930328&response-content-disposition=attachment%3B%20filename%3DBrave-stable-v1.69.147-x86_64.AppImage&response-content-type=application%2Foctet-stream
zsync2: optimized ranges, old requests count 247, new requests count 6

96.95% done (143.21 of 147.71 MiB)...
zsync2: Verifying downloaded file
100.00% done (147.71 of 147.71 MiB)...
zsync2: checksum matches OK
zsync2: used 8167424 local, fetched 151826832
100.00% done (147.71 of 147.71 MiB)...
Validation warning: AppImage not signed
Removing old AppImage: /home/samuel/Local/opt/brave/brave
Update successful. Updated existing file /home/samuel/Local/opt/brave/./brave
chmod: cannot access './brave': No such file or directory

This left me with a brave.zs-old file and deleted the brave appimage.

[Samueru-sama]

Now all that's left is waiting for this PR to get merged.

[Samueru-sama]

The PR has been merged so now we can continue.

[ivan-hc]

the conversion is already in progress, while you are updating old scripts, the new scripts will adopt the template you created. I am doing the same, at least with my Conty-based AppImages.

Thanks for the contribution. I think I can close this issue.