Jruby support?

[chriskilding]

When I tried to use this gem on Jruby 1.7.10 I got the following error, basically it looks like this gem has a hard requirement on the MRI / cruby 'pg' gem at the moment. Could this be fixed to support running on Jruby?

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

    /Users/me/.rbenv/versions/jruby-1.7.10/bin/jruby extconf.rb 
NotImplementedError: C extension support is not enabled. Pass -Xcext.enabled=true to JRuby or set JRUBY_OPTS.

   (root) at /Users/me/.rbenv/versions/jruby-1.7.10/lib/ruby/shared/mkmf.rb:8
  require at org/jruby/RubyKernel.java:1083
   (root) at /Users/me/.rbenv/versions/jruby-1.7.10/lib/ruby/shared/rubygems/core_ext/kernel_require.rb:1
   (root) at extconf.rb:2


Gem files will remain installed in /Users/me/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/gems/pg-0.17.1 for inspection.
Results logged to /Users/me/.rbenv/versions/jruby-1.7.10/lib/ruby/gems/shared/gems/pg-0.17.1/ext/gem_make.out
An error occurred while installing pg (0.17.1), and Bundler cannot continue.
Make sure that `gem install pg -v '0.17.1'` succeeds before bundling.

[diogob]

The thing is, I don't have a JRuby env to test the gem, but I believe it could work with a JDBC adapter and some tweaks in the code. Beware that I use some methods of the pg raw interface, that's why there is a dependency. But If you want to do this and send me a PR I'll gladly merge it ;)

[chriskilding]

Not able to do a full PR for you at this time, but here's some code that Worked For Me:

require 'java'
require "jdbc/postgres"
...
# Ensure you are using absolute path for safety
path = File.expand_path [some path], __FILE__

# Load DB driver
Jdbc::Postgres.load_driver

# Load the JDBC underlying connection
connection = [some model].connection.jdbc_connection

# Invoke some Java to let us use the COPY command
# not allowed to do that normally by the JDBC driver.
copier = org.postgresql.copy.CopyManager.new(connection)
istream = java.io.FileInputStream.new path
copier.copyIn("COPY [pluralised lower case model name] FROM STDIN WITH (FORMAT CSV, HEADER TRUE, DELIMITER ',')", istream)

If you want to have a crack at integrating this into the gem, setting up a jruby env is trivial - rbenv install jruby-[version] will do, the rvm equivalent is probably also a one-liner.

[aditya-sanghi]

@themasterchef I am doing copier.copyIn("\copy order_transactions TO '/tmp/foo.csv' DELIMITER E'\t' CSV HEADER")

but getting following error:

Java::OrgPostgresqlUtil::PSQLException: ERROR: syntax error at or near ""

[diogob]

JRuby support will require some major refactoring. The current code is too brittle to accept different database drivers.
The interface could also receive some love (I would drop the acts_as pattern and pass the model as a dependency).
I see that the test cases are a valuable thing that could be shared between a common gem for MRI and JRuby.
Having said that I'll reopen the issue as a possible enhancement.
If you are reading this thread and would like to see this gem supporting jruby please add a 👍 reaction to this comment.