Notes on building release apk using Github Actions - cordova commandline build

1. The working workflow file for building the modified version of the Moodle app version 4.1.0 is at buildSSSVV.yml
   
   
2. Though the main idea was to clone a private repo similar to this post, one difference was that I used my user's private key instead of adding a separate key-pair as deployment key - that also worked, but I should be careful to remove my private key from the destination repo as soon as I finish my builds.
   
   
3. We must clone the private repo and build the public repo as part of the same job in the github workflow, or else the file would be cleaned up and not available (unless stored as an artifact.) 
   
   
4. One stumbling block preventing builds on the first attempt was to find the correct syntax for the release build using cordova build. Turns out it needs several points which were not clearly discussed at cordova's documentation example, but was mentioned in ionic's documentation example. (Edit - all the flags required are mentioned at https://cordova.apache.org/docs/en/11.x/guide/platforms/android/index.html#using-flags - I had not seen this page earlier.) I did not create a build.json since the commandline switches worked for me. "failed to read key from store" was because I missed the --password parameter, I had put in only the --storePassword parameter. The error was not due to requiring escaping of special characters in the password.
   
   
5. We also need -- -- twice in order to get an apk instead of an aab as the output file, Cordova generate release apk instead of aab - Stack Overflow.
   
   
6. The final correct command to build (at least for this version of cordova android) was
   npx ionic cordova build android --release -- -- --packageType=apk --keystore="~/sssvv_mobile-release-key.keystore" --password=$KEY_PW --storePassword=$KEY_PW --alias=$KEY_ALIAS
   
   
7. Before trying all this, I tried building just an unsigned apk - but jarsigner signing of the unsigned release apk didn't work. I wonder why.
   jarsigner -keystore <keystore_file>  -storepass <storepass> -keypass <keypass> <unsigned_apk_file> <alias_name>
   The apk was not showing the correct icon, and "problem parsing file" when try to install. Maybe this problem is due to some version difference between the java / SDK / build tools on the build machine and the signing machine? No idea.
   
   
8. The technique of using this GUI tool to avoid typing out all the paths - Android APK Signer & Aligner - Luke Alderton - also failed, probably due to the same issue as in the above point, whatever that is. Which is why I went ahead with trying to generate the signed release apk from the workflow itself, as above.