CI, base (binary compatibility), multi-arch discussions

cc: @robertsLando @leerob

It is much trickier to set up CI for this repo, because:

• Binary compatibility is affected by the build base (e.g. binaries compiled on 20.04 can not run on 18.04, Ubuntu vs. EL vs. etc.).
• Node.js is a huge program, and we have to compile multiple versions. It is easy to hit limits of Github Actions.
• We want to compile binaries for different architectures. That usually requires cross-compilation, which is more complicated. It is also possible to compile with native toolchain under emulation, but emulation is very inefficient.
• Others…

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For build base:

I think rhscl/devtoolset-10-toolchain-rhel7 is a great choice. It is RedHat’s certified/official GCC 10 toolchain for Enterprise Linux 7. Compiled binaries are compatible with glibc 2.17 and later. This allows the compiled binaries to run on Ubuntu 14.04+, EL7+ and most other distros. Plus, RedHat’s toolchain is production-grade.

However, RedHat do not provide certified cross toolchains, and only EL8+ supports arm64. Ubuntu does provide official cross toolchains. I think we can use Ubuntu 18.04 as base to compile binaries for architectures other than amd64.

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For workflow:

Each Node.js build takes approx. 1 hour.

At minimum, we have to support Active LTS and 1 maintenance LTS. Optimally, we want to support all maintained versions (Current, Active LTS, maintenance LTSs) and at least 1 recently deprecated LTS.

There are at least three platforms (linux, macos and windows) and at least two architectures (x64 and arm64). Additional platforms may include linuxstatic and alpine. Additional architectures may include armv7 and x86.

So, minimum case: 2 (Node.js versions) * 3 (platforms) * 2 (architectures) = 12 builds. worst case: 5 * 5 * 4 - 10 (no armv7/x86 for macOS) - 15 (no x86 for Linux platforms) = 75 builds.

Either way, it is impossible to run full CI frequently, unless you want to get an “excessive usage” email (or bill) from Github (well, idk if they really care, though).

I think we should use workflow_dispatch event, so CI is triggered manually only. We should also try to split jobs of different versions/platforms/archs, so we can choose to rebuild only the necessary ones.

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[leerob]

Added secrets for RHEL for GitHub Actions CI environment.

[robertsLando]

Well done @jesec ! BTW yeah I think that zip executable or compressed file system could be a way