Can't use with ActiveRecord

[dwbutler]

I tried using this gem as a drop-in replacement for pg while attempting to get Discourse to run on JRuby.

Due to this line, the ActiveRecord Postgresql adapter is unable to recognize this gem as satisfying its requirements. I always get:

Gem::LoadError: Specified 'postgresql' for database adapter, but the gem is not loaded. Add `gem 'pg'` to your Gemfile.

I was able to get things to work by forking the gem and editing the gemspec.

I'm not sure what the correct long-term approach is. Either ActiveRecord should be fixed (ideal?), or the gem method itself needs to be patched (ugly?).

[headius]

Yeah, this is kinda why we'd really like to get jruby-pg rolled into the pg gem, so that dependencies are just resolved as normal.

[headius]

I just filed this, so hopefully sometime soon we might be able to get a -java version of the pg gem: https://bitbucket.org/ged/ruby-pg/issue/177/incorporate-jruby-version-of-pg-gem-for-a

In the short term, one thing you could do to help us would be to clone jruby-pg and modify it to produce a pg-####-java.gem instead of jruby-pg-####-java.gem. That should allow your dependencies to resolve and you can see if it works.

[dwbutler]

I was able to get the dependencies to work by changing:

 Gem::Specification.new do |s|
-  s.name = "pg_jruby"
+  s.name = "pg"

I'm also working on some other fixes to make this compatible with Discourse, which I'll probably submit in a separate pull request.

Thanks!

[headius]

@dwbutler That works too! Thanks for giving this a try. We'd really like to prove the jruby-pg library is ready (or close to ready) for inclusion into the standard pg gem, and the best way to do that (other than running test cases, which @jvshahid has done a lot of) is getting real users trying it out.

This issue isn't really a bug in jruby-pg per se, but we'll leave it open as a placeholder for getting jruby-pg merged into ruby-pg.

[jvshahid]

I'm working on making the gem compatible with version 0.16 of the C pg gem. I'm getting very close to implementing all the new features. As soon as this is done, I'll open a pull request in https://github.com/ged/ruby-pg?source=c to merge my changes.

[jvshahid]

See ged/ruby-pg#1

[pmontrasio]

I run into this problem now, after having seen the announcement of JRuby 9000 and tried to run a Rails 4.2 application with it. I could fork the gem and apply the patch from @dwbutler but haven't been any progresses since December 2013?

[Ch4s3]

👍