Koala breaks with faraday 2.0 release `File does not exist: net/http/post/multipart`

[ericmustin]

• This is a Koala bug/issue/documentation problem.

Hello y'all. I help maintain Opentelemetry-ruby, which supports tracing instrumentation for the Koala gem. We noticed the Koala instrumentation test suite is broken in CI in opentelemetry-ruby, here's a test run thats failing

Relevant debug output

Installing faraday 2.0.0
Fetching koala 3.0.0
Installing koala 3.0.0
Bundle complete! 19 Gemfile dependencies, 43 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
opentelemetry-instrumentation-koala: appraisal
>> bundle check --gemfile='/home/runner/work/opentelemetry-ruby/opentelemetry-ruby/instrumentation/koala/gemfiles/koala_3.gemfile' || bundle install --gemfile='/home/runner/work/opentelemetry-ruby/opentelemetry-ruby/instrumentation/koala/gemfiles/koala_3.gemfile' --retry 1
Your Gemfile lists the gem koala (~> 3.0.0) more than once.
You should probably keep only one of them.
Remove any duplicate entries and specify the gem only once.
While it's not a problem now, it could cause errors if you change the version of one of them later.
Resolving dependencies...
The Gemfile's dependencies are satisfied
opentelemetry-instrumentation-koala: test
>> BUNDLE_GEMFILE=/home/runner/work/opentelemetry-ruby/opentelemetry-ruby/instrumentation/koala/gemfiles/koala_3.gemfile bundle exec rake test

File does not exist: net/http/post/multipart

So, net/http/post/multipart is a file from the gem https://github.com/socketry/multipart-post, which isn't required by koala, but instead it's required by faraday, a koala dependency.  However, the issue is that koala adds faraday as a dependency without any version constraint( see here). Faraday just cut a 2.0 release this morning(upgrade guide here), the 2.0 release is chok-ful-o breaking changes, including ripping out it's middleware into separate gems. One of those now "not included by default" middleware gems is faraday-multipart which is what brings in that socketry/multipart-post gem. (see here). Since that's not part of Faraday 2.0, koala raises an exception when it attempts to use that now missing nested dependency.

I am not sure the "right" way to fix this, but I imagine it's to either add a max version of <2.0 to this gemspec, or to add the relevant middleware from faraday that Koala is leveraging as a dependency as well.

Lmk if there's any more info needed on the above. Not super familiar with this library tbh, but happy to contribute a PR to fix this, just not sure what direction y'all want to take.

[ylecuyer]

Thanks for the really well detailed report, I'll have a look at what can be done here, meanwhile your workarround setting a max version of < 2 for faraday will allow you to continue using the gem

[ylecuyer]

I'd suggest the following:

1. add faraday < 2 to the runtime dependency and release a 3.1.0
   2.1 Remove the multipart hack introduced in OAuthException: (#100) properties must be a dictionary #125 I tried and couldn't reproduce. I'll do more testing tomorrow just to be sure
   2.2 Upgrade the gem to be compatible with faraday 2 following their upgrading guide https://github.com/lostisland/faraday/blob/main/UPGRADING.md
   2.3 add faraday > 1, < 3 to the runtime dependency and release a 4.0.0

I do not think it is worth having koala supporting both farday 1 and farday 2 at the same time. The gem is well done and does not need updates when facebook releases new API versions. If a security fix is needed or a feature really needs to be added, backporting to the 3.x should be easier.

@arsduo WDYT? Would you be able to help with the releasing process on rubygems?

[ylecuyer]

Part 1 of the plan is ready and release 3.1.0 should be out soon (#663)

@ericmustin I checked with the opentelemetry projects and everything is OK https://github.com/ylecuyer/opentelemetry-ruby/runs/4845955846?check_suite_focus=true and https://github.com/ylecuyer/opentelemetry-ruby/pull/1/files

regarding the plan, I also added 3.x support so that we don't have to do another release when ruby 3 will be mainstream

Later this week I'll work on the part 2 of the plan adding faraday 2 support

[ericmustin]

ok, sounds good, thanks for the quick help here!

[jimtng]

I came across this issue just now. Another gem needs Faraday 2, so I had to downgrade koala to 3.0.0