remove APIGen project

[bollhals]

Proposed Changes

Removes the ApiGen project and brings code into separate files (resolves #742)

Types of Changes

What types of changes does your code introduce to this project?
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• Bug fix (non-breaking change which fixes issue Re-consider per-build AMQP API generation #742)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)

Checklist

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• I have read the CONTRIBUTING.md document
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• All tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in related repositories

[bollhals]

I have created a new PR for this, as it was too difficult to update the old one.

There are more changes coming for formatting and stuff (similar to original PR #877), which I'll add as separate commits.

[michaelklishin]

@bording @danielmarbach @stebet @lukebakken @kjnilsson before I pull the trigger on this, any last minute objections to removing the API generator? The protocol doesn't change often but we do add things to it occasionally. I personally think it'd be a great simplification to the build system and the codebase, so we should do it, and maybe other clients will follow suit eventually. But maybe it's just me :)

[danielmarbach]

I agree it can go. Makes it also simpler to understand and evolve if needed

[stebet]

I agree as well. Makes it simpler to build and make beneficial changes.

[bollhals]

@reviewers, look at the actual changes made in the commits after the first one. The first is the removal of the project (split of the generated code into their own classes, and removal of the old generator project)

Changes:

• I removed all I... interfaces (e.g. IBasicDeliver, IConfirmSelect) as they were not used at all anywhere.
• I removed all AppendArgumentDebugStringTo methods, as they were not used at all anywhere
• Unified rpc handling

[bollhals]

Ok I think this is done from my side. This can be reviewed.

One thing that I saw was some simplifications around method / class id. I'll check this out in a separate PR.

[bollhals]

Build is still failing. Am I missing something or does this not have the desired effect?

[lukebakken]

I had to fix some scripts - #924 (comment)

[lukebakken]

@michaelklishin I just fixed up concourse to take this change into account. Thanks for reviewing and merging.

https://github.com/rabbitmq/rabbitmq-ci/commit/2d3e9680c2aafb79446437e486b7b2ad491c5901