Gems in a jar can't be required from code

[blerins]

Hi!

I'm using gems-in-a-jar (http://blog.nicksieger.com/articles/2009/01/10/jruby-1-1-6-gems-in-a-jar/) for packaging an application, but I'm having trouble with it, I can't require the jar from within code:

$ jar tf andlib.jar 
META-INF/
META-INF/MANIFEST.MF
gems/
gems/andand-1.3.3/
gems/andand-1.3.3/test/
gems/andand-1.3.3/test/test_helper.rb
gems/andand-1.3.3/test/andand_spec.rb
gems/andand-1.3.3/License.txt
gems/andand-1.3.3/lib/
gems/andand-1.3.3/lib/andand/
gems/andand-1.3.3/lib/andand/version.rb
gems/andand-1.3.3/lib/andand.rb
gems/andand-1.3.3/History.txt
gems/andand-1.3.3/README.textile
build_info/
cache/
cache/andand-1.3.3.gem
doc/
specifications/
specifications/andand-1.3.3.gemspec

$ java -jar jruby-complete.jar -v
jruby 1.7.13 (1.9.3p392) 2014-06-24 43f133c on OpenJDK 64-Bit Server VM 1.7.0_55-b14 [linux-amd64]

$ java -jar jruby-complete.jar -I . -randlib.jar -S irb
irb(main):001:0> require 'andand'
=> true
irb(main):002:0> exit

$ java -jar jruby-complete.jar -I . -S irb
irb(main):001:0> require 'andlib.jar'
=> true
irb(main):002:0> require 'andand'
LoadError: no such file to load -- andand
    from org/jruby/RubyKernel.java:1065:in `require'
    from file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/rubygems/core_ext/kernel_require.rb:55:in `require'
    from (irb):2:in `evaluate'
    from org/jruby/RubyKernel.java:1101:in `eval'
    from org/jruby/RubyKernel.java:1501:in `loop'
    from org/jruby/RubyKernel.java:1264:in `catch'
    from org/jruby/RubyKernel.java:1264:in `catch'
    from file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/bin/jirb:13:in `(root)'
    from org/jruby/RubyKernel.java:1081:in `load'
    from file:/home/bruno/javajars/jruby-complete.jar!/jruby/commands.rb:1:in `(root)'
    from jirb:1:in `(root)'
irb(main):003:0> exit

Thanks

[ratnikov]

Any specific reason (documentation that might need to be fixed) that you expect it to work?

After all, requiring the JAR will merely add it to classpath but doesn't really muck with $LOAD_PATH which is used to resolve requires, so the fact that you're getting the error is fully expected.

What you should do is fix the GEM_PATH to point to the contents of the jar, e.g. GEM_PATH=file:/.../andlib.jar!

[mkristian]

I also wanted to add that added the andlib.jar to classpath via the command line helps.

not sure why that works better than the require 'andlib'

[blerins]

I don't get which is the difference between argument:
-rlibrary require the library, before executing your script

And doing a require 'library' on ruby code

As you can see, just the second example fails.

[blerins]

In both cases $LOAD_PATH and ENV['GEM_PATH'] seem to be the same:

$ PATH=/bin:/usr/bin java -jar jruby-complete.jar -I . -S irb
irb(main):001:0> $LOAD_PATH
=> [".", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/1.9/site_ruby", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/1.9"]
irb(main):002:0> ENV['GEM_PATH']
=> nil
irb(main):003:0> exit

$ PATH=/bin:/usr/bin java -jar jruby-complete.jar -I . -randlib -S irb
irb(main):001:0> $LOAD_PATH
=> [".", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/1.9/site_ruby", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared", "file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/1.9"]
irb(main):002:0> ENV['GEM_PATH']
=> nil
irb(main):003:0> exit

[blerins]

For $CLASSPATH, after doing the require it seams the same too:

$ PATH=/bin:/usr/bin java -jar jruby-complete.jar -I . -randlib -S irb
irb(main):001:0> $CLASSPATH
=> ["file:/home/bruno/javajars/andlib.jar", "jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/jline-2.11.jar", "jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/readline.jar"]
irb(main):002:0> exit

$ PATH=/bin:/usr/bin java -jar jruby-complete.jar -I . -S irb
irb(main):001:0> $CLASSPATH
=> ["jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/jline-2.11.jar", "jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/readline.jar"]
irb(main):002:0> require 'andlib'
=> true
irb(main):003:0> $CLASSPATH
=> ["jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/jline-2.11.jar", "jar:file:/home/bruno/javajars/jruby-complete.jar!/META-INF/jruby.home/lib/ruby/shared/readline/readline.jar", "file:/home/bruno/javajars/andlib.jar"]
irb(main):004:0> exit

[ratnikov]

I think classpath discussion is a red herring.

Here's what's definitely working:

build gems.jar with thread_safe gem in it
$ GEM_HOME=$(mktemp -d) && gem install thread_safe && jar cf gems.jar -C "$GEM_HOME" .

Load the thread_safe from the gems.jar (with jruby 1.7.13)
$ GEM_HOME= GEM_PATH=jar:file:$PWD/gems.jar'!' ruby -e 'require "thread_safe"'

Note that technically GEM_PATH should be set to jar:file:$PWD/gems.jar! but I have to escape '!' to avoid bash treating it specially.

@blerins can you verify that that works for you?

[blerins]

Yes, even just with setting only GEM_PATH:

$ GEM_PATH=jar:file:$PWD/andlib.jar'!' PATH=/bin:/usr/bin java -jar jruby-complete.jar -I . -S irb
irb(main):001:0> require 'andand'
=> true
irb(main):002:0> exit

[ratnikov]

Excellent! So are you good to go (and we can close this issue)?

[mkristian]

alternatively
java -cp andlib.jar:jruby-complete.jar org.jruby.Main -S irb
will do as well.

[blerins]

Well, I'm good to go, but I still think that doing require 'andlib' from code should work, It adds the jar to the classpath, wouldn't that be enough? (look at the last example of @mkristian)
It seems like a bug to me.

Anyway, thanks a lot guys!!

[mkristian]

@blerins my example uses a different classloader
but -randlib and require 'andlib' should behave the same - IMO

[mkristian]

there is a lot of refactoring going on around "require" right now. and it seems to be consensus that requiring a jar should not add its gems to rubygems auto-magically.