Re: [PATCH] limit rack version for ruby compatibility

[Adam Duke <adamduke@twitter.com>]

Following up on this, it seems to me like keeping the Ruby 2.2.2
requirement is the right way to go for rack. If the unicorn project
wants to continue support for older rubies, the unicorn gemspec should
be changed to limit the rack dependency to '< 2'. If rack 2.0.0 is
released and there is no limit on the dependency in unicorn's gemspec,
it seems to me like any deployments that are not running Ruby 2.2.2
will fail.

From 2f3b39edb5d477e0efcbe5ce55af37ddea289e9e Mon Sep 17 00:00:00 2001
From: Adam Duke <adam.v.duke@gmail.com>
Date: Fri, 8 Jan 2016 13:06:31 -0500
Subject: [PATCH] limit rack version for ruby compatibility

rack introduced a dependency on ruby 2.2.2 or greater in
https://github.com/rack/rack/commit/771d94e5dbe53058160a1f8a4cc56384c1d2a048

In order to maintain support for ruby versions less than 2.2.2, limit
the rack dependency to supported versions for the current ruby.
---
 unicorn.gemspec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/unicorn.gemspec b/unicorn.gemspec
index 1099361..16607ac 100644
--- a/unicorn.gemspec
+++ b/unicorn.gemspec
@@ -35,7 +35,7 @@
   # up/downgrade to any other version, the Rack dependency may be
   # commented out.  Nevertheless, upgrading to Rails 2.3.4 or later is
   # *strongly* recommended for security reasons.
-  s.add_dependency(%q<rack>)
+  s.add_dependency(%q<rack>, '< 2')
   s.add_dependency(%q<kgio>, '~> 2.6')
   s.add_dependency(%q<raindrops>, '~> 0.7')

-- 
2.6.4

On Fri, Jan 8, 2016 at 6:19 PM, Aaron Patterson
<tenderlove@ruby-lang.org> wrote:
> On Fri, Jan 08, 2016 at 10:37:32PM +0000, Eric Wong wrote:
>> Aaron Patterson <tenderlove@ruby-lang.org> wrote:
>> > The main reason I bumped it up to Ruby 2.2.x is because that will be the
>> > minimum version of Ruby I'll be stuck with throughout Rack 2.x's
>> > lifetime.  IOW, I can't drop Ruby versions in anything but a major
>> > release so I'm being conservative and only going with the latest (at the
>> > time that was 2.2).
>> >
>> > I could be convinced to bring down the version number, but I'd like to
>> > know why first. :)
>>
>> Because other people are _always_ slow to upgrade :)
>
> Yes, exactly. I am betting that by the time people upgrade to Rack 2.0,
> Ruby 2.2.2 will be old hat (Ruby 2.3 has been released already!)  ;)
>
>> However, I suppose it's fine to bring the requirement up with a
>> major version bump of Rack.  I don't want to burden you with
>> old cruft, either.
>>
>> unicorn may also be able to drop the dependency on rack by
>> lazy loading:
>>
>> * Rack::Utils::HTTP_STATUS_CODES is the main thing we use from
>>   Rack at runtime; and unicorn would actually function fine if
>>   the hash were empty; HTTP status lines would just be short
>>   and non-descriptive.
>>
>> * The Rack::Builder dependency can be optional, even.
>>
>> Fwiw, I plan to support Rack 1.x and Ruby 1.9.3 under unicorn for a few
>> more years because of LTS distros.  New versions take priority, of
>> course.
>
> Ok.  Let me know if there's anything I can do to help.  Removing the
> strict requirement from the gemspec *is* on the table, as long as we
> document the supported versions in the README.  I don't plan on using
> anything that would be specific to Ruby 2.2.2 and up, but I don't want
> to be burdened by older ones either.  A simple comment in the README
> would suffice.
>
> --
> Aaron Patterson
> http://tenderlovemaking.com/