tebako-packer doesn't support the new ./exe binary directory

[bradgessler]

Took me a while to figure this out, but the packaging scenarios at https://github.com/tamatebako/blob/a1d21fb64f8df2b849f7d1696f2f1c86ff0a80af/README.adoc#L1002-L1021 won't work gems created via bundler gem.

By default, bundler gem blah creates an ./exe directory, which is defined in the gemspec via spec.bindir = "exe". This changed from a few years ago when binaries were stored in ./bin, but this path has since been reserved for developers binary stubs, for bundler, and the exe folder is reserved for the binaries that are to be distributed.

I think the best approach might be for Tebake to find the gemspec, load it, ask for the bindir, and use that path.

I haven't tracked down in the code where this is happening, but I'm guessing the bin path is hard coded.

For now my work around is to throw the ./exe/blah file into ./bin/blah and get it running.

[bradgessler]

Another proposal: it might make sense to pass the path into the —entry-point argument. For example —entry-point=exe/blah instead of —entry-point=blah with the implicit bin prefix.

I don't understand the project well enough to know if there's a reason entry-point doesn't have a folder in front of it, but I'd guess there's a reason.

[ronaldtse]

Thank you @bradgessler for the feedback (and the recent PR #213 )!

I think the best approach might be for Tebake to find the gemspec, load it, ask for the bindir, and use that path.

As you realize the entrypoint is currently defined using the --entry-point argument, and any implicit prefixes for legacy compatibility is probably moot at this point since Tebako does not need to be compatible with ruby-packer (that was the original motivation).

I believe it is time we take a clean look at how to make entrypoint definitions (we have previously discussed a Tebafile):

• gem: check gemspec for executables (but we can only have one..., so the user still needs to choose)
• command line exe: specify directly without adding any prefix

[maxirmx]

Hi, @bradgessler

You are three times right :)

• bin is hardcoded
• tebako shall parse gemspec (and also Gemfile.lock) and do not make silly assumptions
• we shall remove implict prefixes from --entry-point argument

if you are interested in details you can look at maxirmx-separate-runtime branch. Somewhere between scenario_manager.rb and deploy_helper.rb

Main branch has the same logic implemented in CMake script that would be very hard to change.

[maxirmx]

After revisiting this issue I do not see any errors or unsupported features
Tebako 100% depends on gemspec and gem install command

There is no ./exe binary directory in specification.
gemspec can define bindir and executables within bindir

Specification explicitly says "You don’t specify the full path (as in bin/rake); all application-style files are expected to be found in bindir", tebako follows this convention and expects the entry-point executable to be found in bindir as defined in gemspec

There is also bindir option of gem install command

-n, --bindir DIR - Directory where executables will be placed when the gem is installed

Tebako sets this option to a path within memfs like \__tebako_memfs__\bin which is actually gem install default (the folder where Ruby executable resides). In any case the specification does not say that gem install bindir option can be set or restricted by a gem in any way.

So I believe that tebako relies follows specifications. I have added some tests for different bindir settings in gemspec and included this information to tutorial.