remove local golang dependency for ocb binary

[jackgopack4]

Is your feature request related to a problem? Please describe.
ocb binaries, even as they are compiled and built for specific architectures, still require a golang environment to run. This seems counterintuitive; I might expect go install command or compiling from scratch to require golang compiler, but I wouldn't expect a compiled binary to still require golang in the environment

Describe the solution you'd like
I would like to remove the golang dependency for the ocb binary, allowing users to run ocb in a minimal (e.g. scratch, alpine, etc.) environment

Describe alternatives you've considered
Alternative is adding some explicit mention of golang requirement for ocb in documentation, both on github and opentelemetry.io

Additional context
I have been working on and submitted open-telemetry/opentelemetry-collector-releases#671 which has a "thicker" image than required due the golang dependency for ocb binary. Making this change would allow a smaller image, such as from scratch that the collector distros run on.

[jackgopack4]

In my opinion, the quickest solution would be embedding the appropriate version of the golang compiler into ocb binary; this would necessarily raise the size of the ocb binary by around ~75MB.
However, I'm not even certain this is possible. Doing some more investigation to see if I can find any examples of this.

I am also looking into whether I could import golang's cmd/compile or go/build packages as a dependency and call the go build functions in code instead of running as a command.

Alternatively it might also be possible to use the command-line execution functionality of ocb to download and install go binary into a local path if it does not find it installed in PATH.

[Annosha]

Hi @jackgopack4 I'm an Outreachy applicant. If the documentation part of this issue is open and beginner friendly can I work on it?

[jackgopack4]

Absolutely, feel free to take a crack at it. I think it will be up for discussion whether this is a feature the maintainers want to include (certain security concerns with a program that downloads another binary and executes it on your behalf) but if it is a desired feature, it shouldn't be too complicated, code-wise.

[andrzej-stencel]

I don't think embedding the Go compiler in the OTel Collector Builder binary is the way to go. The builder's purpose is to generate the sources for a distro and then use the Go compiler to compile the sources. Go compiler is an external dependency of the Builder and in my opinion it should stay like that.

I have commented on open-telemetry/opentelemetry-collector-releases#671 too. Thanks Jack and sorry for the confusion I caused!