Sentry fails without hackney at runtime but is fine at compile time

[andrew-combs]

Environment

~> 8.0

Steps to Reproduce

1. Fail to include :hackney in your application deps; use the default hackney adapter
2. Include something like {:excoveralls, "~> 0.15", only: [:dev, :test]} in mix.exs
3. Add Logger.add_backend(Sentry.LoggerBackend) to application.ex`
4. Compile and run

Expected Result

Sentry should fail to compile due to the missing dependency.

Actual Result

Sentry compiles and runs in dev and test environments (because excoveralls happens to require hackney), but crashes at runtime in prod.

Notes

This is really more of an improvement to dev/x. Because of a circumstantial issue where hackney was brought in from another project in a non-prod environment, things appeared to work fine out of the box. However, once deployed to prod, sentry blows up because suddenly hackney is missing. Since this is something that can be known at compile-time, it would save a bit of headache to catch it then if possible.

[rlopzc]

I wouldn't say is just a dev/x improvement. It literally broke our production system by not having hackney at runtime

[whatyouhide]

Fixed in #554.