msgpack/v4 branch no longer exists

[jdub]

Entertainingly, the v4 branch of msgpack no longer exists, which breaks non-module builds that depend on libhoney-go. I have also reported the issue upstream.

[vmihailenco]

I've created v4 branch, but I did not delete v4 - it never existed. I believe it was working as long as there was no v5. Which is understandable but still surprising.

[jdub]

Thanks @vmihailenco – Vladimir created the v4 branch, so I'll close this issue now.

[jdub]

I have created a gopkg.in-based solution to fix libhoney-go's vmihailenco/msgpack v4 dependency for non-modules users.

[lizthegrey]

This fix introduces another bug :(

#79 (comment)

[lizthegrey]

We have two paths forward to unbreak things for non-module users on modern golang1.13+:
(1) Get Github's Dependabot team to fix dependabot/gomodules-extracted#5, and then de-support go1.12 (including the module users)
(2) Get @vmihailenco to change the canonical package name of msgpack library to use gopkg.in going forward, which would enable go1.12 module users, go1.13+ module users, and non-module users on any golang version to all be happy at the cost of having to add a replace directive or changing their import paths.

[lizthegrey]

(2) is not planned, and instead the proposed solution is to default to msgpack v5 branch.

[MikeGoldsmith]

Closing as I believe #127 fixed the issue.