Faraday 2.0 Alpha

[iMacTia]

Faraday 2.0.0.alpha-1

This is the first alpha release for the upcoming Faraday 2.0 major release 🎉 .
Please note, this version is not production ready, but we'd appreciate everyone feedback if you have the chance to try it in your personal projects 🙌.

To learn more about how to safely upgrade to Faraday 2.0 and update your code, please checkout our UPGRADING guide!

And you have any feedback, please feel free to join us in Discussions 💬 !

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This discussion was created from the release v2.0.0.alpha-1.

[mattbrictson]

Hi! Thanks for all your work on getting Faraday 2.0 ready.

I'm wanting to try 2.0.0.alpha.pre.1 on a personal project, as suggested in the release notes. But my project also requires faraday_middleware. I don't see any way to use faraday_middleware in conjunction with faraday >= 2.0.0.alpha.pre.1 because the gemspec is incompatible: it is pinned to ~> 1.0.

https://github.com/lostisland/faraday_middleware/blob/61b1422c831434caa1d84ab35e2e77f1ada39679/faraday_middleware.gemspec#L19

Any suggestions?

[mattbrictson]

Oh! I just found that the json middleware has been moved into the core faraday gem: #1300. That is big news because it is the whole reason I have the faraday_middleware dependency. Now that it is in core, I don't need the extra gem.

Maybe this should be mentioned in the UPGRADING guide? I suspect many developers will be in the same boat.

[iMacTia]

That's a really great point, thank you for the feedback @mattbrictson 🙌 !
It's not a strict compatibility requirement, that's why I didn't included it in the UPGRADING file and was instead leaving that for the release notes, but you got a point on the interoperability with faraday_middleware, so it should definitely be mentioned 👍 !

Thank you so much for trying the 2.0 alpha and providing feedback, this is invaluable for us 🙇 !

[mattbrictson]

I am still a bit stuck on how to use the 2.0 alpha.

It looks like the adapter setting is being ignored. Here is a simple script:

require "bundler/inline"

gemfile do
  source "https://rubygems.org"
  gem "faraday", "2.0.0.alpha.pre.1"
  gem "faraday-net_http"
end

conn = Faraday.new do |builder|
  builder.adapter :net_http
end

conn.get("https://github.com/")

This blows up:

gems/faraday-2.0.0.alpha.pre.1/lib/faraday/middleware_registry.rb:57:in `lookup_middleware': :test is not registered on Faraday::Adapter (Faraday::Error)
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/rack_builder.rb:114:in `adapter'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/rack_builder.rb:77:in `build'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/rack_builder.rb:65:in `initialize'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/options/connection_options.rb:19:in `new'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/options/connection_options.rb:19:in `new_builder'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday/connection.rb:81:in `initialize'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday.rb:96:in `new'
  from gems/faraday-2.0.0.alpha.pre.1/lib/faraday.rb:96:in `new'
  from faraday.rb:9:in `<main>'

Digging through the faraday source, I see that it falls back to an adapter named :test if no adapter is specified. But then :test is apparently an invalid adapter name, hence the exception.

A couple points of confusion here:

1. Why is faraday ignoring builder.adapter :net_http? Do I have that written incorrectly?
2. If I am using the builder API wrong, why am I not getting an ArgumentError?
3. :test is not registered on Faraday::Adapter is a very confusing error for someone not intimately familiar with the faraday source code. Could this be improved for users who forget to specify an adapter?

[mattbrictson]

It looks like the block passed to Faraday.new is not being evaluated at all. For example, the raise in this code is never reached:

conn = Faraday.new do |builder|
  raise "wat"
  builder.adapter :net_http
end

[iMacTia]

Hi @mattbrictson and thanks once more for testing the alpha!
I was working on this last weekend and I noticed that we have a somewhat complicated setup in the rack builder where a stack is first created without any config (hence defaulting to the default adapter) and only AFTER this, the actual block you provide is called.
This normally works because the custom block will simply override the default configuration, but I agree it should be refactored at some point. (if interested, here is where we do that)

Since you get an exception during the first step, then the code won't reach your block, explaining why you don't see the exception.
Long term solution would be to improve the rack builder, but since I'm aiming for a major rewrite after 2.0, I'd just fix the issue with the test adapter for now and that should solve the problem.

I believe the actual issue we're looking at has to do with loading, I'll take a look immediately

[iMacTia]

As I thought, the test adapter is not required anywhere except during rspec. I just pushed a commit to fix that, and released alpha-2. Your code works for me replacing the faraday version with 2.0.0.alpha.pre.2 🙌

[mattbrictson]

Great! Confirmed it is now working with 2.0.0.alpha.pre.2. Thanks!

[mattbrictson]

One more question: what is the status of faraday-net_http_persistent?

If I try this code:

require "bundler/inline"

gemfile do
  source "https://rubygems.org"
  gem "faraday", "2.0.0.alpha.pre.2"
  gem "faraday-net_http_persistent"
end

conn = Faraday.new do |builder|
  builder.adapter :net_http_persistent
end

conn.get("https://github.com/")

Then I get this exception:

gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:6:in `<class:Adapter>': uninitialized constant Faraday::Adapter::NetHttp (NameError)
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:4:in `<module:Faraday>'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:3:in `<top (required)>'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/net_http_persistent.rb:3:in `require_relative'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/net_http_persistent.rb:3:in `<top (required)>'
  from site_ruby/3.0.0/bundler/runtime.rb:73:in `require'
  from site_ruby/3.0.0/bundler/runtime.rb:73:in `rescue in block in require'
  from site_ruby/3.0.0/bundler/runtime.rb:51:in `block in require'
  from site_ruby/3.0.0/bundler/runtime.rb:44:in `each'
  from site_ruby/3.0.0/bundler/runtime.rb:44:in `require'
  from site_ruby/3.0.0/bundler/inline.rb:71:in `block in gemfile'
  from site_ruby/3.0.0/bundler/settings.rb:131:in `temporary'
  from site_ruby/3.0.0/bundler/inline.rb:55:in `gemfile'
  from faraday.rb:3:in `<main>'

So it looks like there is an implicit, undeclared dependency on the faraday-net_http gem?

If I then explicitly add gem "faraday-net_http" to my gemfile, then I get a different error:

gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:7:in `<class:NetHttpPersistent>': undefined method `dependency' for Faraday::Adapter::NetHttpPersistent:Class (NoMethodError)
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:6:in `<class:Adapter>'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:4:in `<module:Faraday>'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/adapter/net_http_persistent.rb:3:in `<top (required)>'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/net_http_persistent.rb:3:in `require_relative'
  from gems/3.0.0/gems/faraday-net_http_persistent-1.2.0/lib/faraday/net_http_persistent.rb:3:in `<top (required)>'
  from site_ruby/3.0.0/bundler/runtime.rb:73:in `require'
  from site_ruby/3.0.0/bundler/runtime.rb:73:in `rescue in block in require'
  from site_ruby/3.0.0/bundler/runtime.rb:51:in `block in require'
  from site_ruby/3.0.0/bundler/runtime.rb:44:in `each'
  from site_ruby/3.0.0/bundler/runtime.rb:44:in `require'
  from site_ruby/3.0.0/bundler/inline.rb:71:in `block in gemfile'
  from site_ruby/3.0.0/bundler/settings.rb:131:in `temporary'
  from site_ruby/3.0.0/bundler/inline.rb:55:in `gemfile'
  from faraday.rb:3:in `<main>'

It is not clear to me what that means. Any idea what is causing this? Perhaps faraday-net_http_persistent is not compatible with 2.0 yet?

[iMacTia]

I have a PR open that fixes this issue for net_http now: lostisland/faraday-net_http#9
I'll go through the other adapters as well, but I don't think I'll update them all before the final v2.0 is released.
My approach would be to proceed with a community interest-based priority

[iMacTia]

@mattbrictson PR merged and faraday-net_http v2.0.0.alpha-1 have been released 🎉

[mattbrictson]

I also opened this PR to make faraday-net_http_persistent compatible with 2.0: lostisland/faraday-net_http_persistent#7

[iMacTia]

Ahaha sorry @mattbrictson I totally missed that and opened one myself 🙈 lostisland/faraday-net_http_persistent#8

I like the changes you made to the README as well, and it seems like you kept net-http-persistent v3 compatibility, which I didn't.
Feel free to cherry-pick any other change from my PR (which I'm going to close now). Any further commit you do to your branch will now be built as I've reactivated the CI workflow 👍

[olleolleolle]

@mattbrictson Thanks so much for making that PR, we are rolling!