[build] Add Android build action to GitHub CI

[maxsharabayko]

Add Android build CI action with NDK R23.

TODO

• How to properly set script dir?

[maxsharabayko]

When running from Github CI Action, the initial SCRIPT_DIR value is correct, while after auto-detection it becomes kinda invalid.
@sergeiignatov could you advise what would be the best way to resolve this? Maybe allow passing SCRIPT_DIR as an argument of the script?

SCRIPT_DIR: /home/runner/work/srt/srt/scripts/build-android
uname: Linux
readlink -f $0: /home/runner/work/_temp/01987a7f-8cc7-4d32-818f-f57770e2a163.sh
New SCRIPT_DIR: /home/runner/work/_temp

[sergeiignatov]

@maxsharabayko I suggest to create new script, like build-android-ci, that will call mkssl/mkmbedtls and mksrt.
Not only path detection should be changed, but

• build-android:96 will clone srt repository each time but travis build will use own working copy;
• build-android:86 same clone logic for mbedtls repo;
• mkssl:20 will download openssl on each build and this should go to build-android:82 to be more consistent.

[sergeiignatov]

@maxsharabayko it s not not required to re-build openssl on each push. This will be waste of time. Do the following: comment out srt part from build-android and run it on local machine with -e openssl and then with -e mbedtls.

You will get "sysroots" for 4 architectures in working directory. Copy it somewhere to travis machine, then just pass $INSTALL_DIR to mksrt.

mksrt -n NDK_ROOT -a 21 -t arm64-v8a -e openssl -s /path/to/srt/repo/root -i /travis/prebuilt_android_enc_libs/arm64-v8a

[maxsharabayko]

You will get "sysroots" for 4 architectures in working directory. Copy it somewhere to travis machine, then just pass $INSTALL_DIR to mksrt.

I am not sure if we could store them on the CI machine provided by GitHub, but we could create a dedicated repository to store those binaries there, and just download them instead of building each time. 🤔

I still wonder though why do you suggest creating a separate script? The existing one works well except for the SCRIPT_PATH variable. At the moment I have it commented and CI build succeeds.

[sergeiignatov]

I missed last status update, I thought status is still "stuck on openssl build". It's ok to use $(pwd) instead of auto-detection, don't add extra command-line argument.

Also build-android script clones own copy of srt repo (build-android:97). Will it get updated code from pull request's branch?

[maxsharabayko]

Also build-android script clones own copy of srt repo (build-android:97). Will it get updated code from pull request's branch?

Indeed! We already have a working copy of srt source code from the PR locally during the CI action (see the checkout action). Modification to the script is needed to handle this properly.

Currently:

if [ ! -d $BASE_DIR/srt ]; then
 git clone https://github.com/Haivision/srt srt
 if [ ! -z "$SRT_VERSION" ]; then
  git -C $BASE_DIR/srt checkout $SRT_VERSION
 fi
fi

[sergeiignatov]

Done. Script will build working copy: sergeiignatov@423f024

[maxsharabayko]

Thank you, @sergeiignatov !

I assume line 108 can also be removed now, right?

git -C $BASE_DIR/srt clean -fd

Currently it causes the following error:

2021-10-13T08:47:31.9152247Z Before git -C BASE_DIR/srt clean -fd
2021-10-13T08:47:31.9169783Z fatal: cannot change to '/home/runner/work/srt/srt/scripts/build-android/srt': No such file or directory

[sergeiignatov]

No, git clean is still required to move between architectures. And it should ignore work already done inside scripts/build-android.
sergeiignatov@ae918e0 should be final version of script.

[maxsharabayko]

Great, thank you @sergeiignatov !
Android build action is working now!