How can I cache the build output for CI servers?

[NuckChorris]

I've got some tests which run on Github Actions and need a modern ImageMagick (which, of course, Ubuntu and Debian don't provide) so I'm using IMEI to build ImageMagick 7, but this adds 15 minutes to my build. Is there some way I can just compile into a folder, cache that, and then move it into place for each build?

[SoftCreatR]

One thing that COULD work is to use --checkinstall on initial build, and export the generated .deb files, e.g. by committing them into your repo.

[NuckChorris]

Yes, the build is reusing those three, but ImageMagick 7 is not in any of them. The imei-imagemagick_7.1.0-8-imei6.5.3_amd64.deb package is missing when I build in CI but there when I build on my own server 🤔

root@temp-ci-imagemagick-playground:/usr/local/src# ls -l
total 18024
-rw-r--r-- 1 root root 8511860 Sep 20 23:39 imei-imagemagick_7.1.0-8-imei6.5.3_amd64.deb
-rw-r--r-- 1 root root 3552096 Sep 20 23:24 imei-libaom_3.1.2-imei6.5.3_amd64.deb
-rw-r--r-- 1 root root 3958196 Sep 20 23:26 imei-libheif_1.12.0-imei6.5.3_amd64.deb
-rw-r--r-- 1 root root 2422728 Sep 20 23:31 imei-libjxl_0.5-imei6.5.3_amd64.deb

[SoftCreatR]

While I'm not sure about that (some time has passed since my last tests), this could be an issue: In your workflow file, you may first remove imagemagick* first. I remember, that I had some problems when using checkinstall, because it seems that the ubuntu-latest container already has imagemagick installed, which is incompatible with imagemagick we build using checkinstall: https://github.com/SoftCreatR/imei/blob/main/imei.sh#L835

However, if that's the problem, I wonder, why IMEI reports a successful installation 🤔

Then, you might use the --ci option to skip certain things from being done, because in a CI run, they're usually not needed. However, it's not necessary to enable this option, but I wanted to mention that.

[NuckChorris]

I ran apt remove imagemagick before running IMEI and it still is missing the deb for imagemagick:

https://github.com/hummingbird-me/kitsu-server/runs/3681480473?check_suite_focus=true#step:6:93

Gonna see if I can reproduce this on my own server to more easily debug the problem

[NuckChorris]

Great news, that works as long as I apt remove imagemagick imagemagick-* -y first! I think the make install task that checkinstall is running is refusing to overwrite anything which is already there 😅

Hoping to publish this as a Github action to install a specific ImageMagick version, so other people don't have to go through this in future

[SoftCreatR]

Sounds good :)