Allow to define gem in the gemfile with the path option

Fixes #2375

lib/logstash/bundler_patch.rb

@@ -0,0 +1,49 @@
+require 'bundler'
+
+module Bundler
+  class RubygemsIntegration
+    # When you call Bundler#setup it will bootstrap
+    # a new rubygems environment and wipe all the existing
+    # specs available if they are not defined in the current gemfile.
+    # This patch change the behavior and will merge the specs.
+    #
+    # If you use :path to declare a gem in your gemfile this will create
+    # a virtual specs for this gems and add will add them to the $LOAD_PATH
+    #
+    # Future >= rubygems 2.0
+    class Future < RubygemsIntegration
+      def stub_rubygems(specs)
+        merged = merge_specs(specs)
+
+        Gem::Specification.all = merged
+
+        Gem.post_reset {
+          Gem::Specification.all = merged
+        }
+      end
+
+      def merge_specs(specs)
+        merged_array = Gem::Specification.to_a + specs.to_a
+        SpecSet.new(merged_array)
+      end
+    end
+  end  
+
+  # Patch bundler to write a .lock file specific to the version of ruby.
+  # This keeps MRI/JRuby/RBX from conflicting over the Gemfile.lock updates
+  module SharedHelpers
+    def default_lockfile
+      ruby = "#{LogStash::Environment.ruby_engine}-#{LogStash::Environment.ruby_abi_version}"
+      Pathname.new("#{default_gemfile}.#{ruby}.lock")
+    end
+  end
+
+  # Add the Bundler.reset! method which has been added in master but is not in 1.7.9.
+  class << self
+    unless self.method_defined?("reset!")
+      def reset!
+        @definition = nil
+      end
+    end
+  end
+end

lib/logstash/environment.rb

@@ -57,6 +57,22 @@ module LogStash
     # of some plugins dependedant gems.
     def set_gem_paths!
       ENV["GEM_HOME"] = ENV["GEM_PATH"] = logstash_gem_home
+      ENV["BUNDLE_GEMFILE"] = GEMFILE_PATH
+
+      require 'bundler'
+      require 'logstash/bundler_patch'
+
+      Bundler.setup
+
+      # Bundler.setup will wipe the existing $LOAD_PATH.
+      # Since we are using gems not declared in the gemfile we need to
+      # recalculate the $LOAD_PATH with all the available gems
+      load_paths = Gem::Specification
+        .collect(&:load_paths)
+        .flatten
+        .reject { |path| $LOAD_PATH.include?(path) }
+
+      $LOAD_PATH.unshift(*load_paths)
     end
 
     def bundler_install_command(gem_file, gem_path)

rakelib/bundler_patch.rb

@@ -1,20 +0,0 @@
-module Bundler
-
-  # Patch bundler to write a .lock file specific to the version of ruby.
-  # This keeps MRI/JRuby/RBX from conflicting over the Gemfile.lock updates
-  module SharedHelpers
-    def default_lockfile
-      ruby = "#{LogStash::Environment.ruby_engine}-#{LogStash::Environment.ruby_abi_version}"
-      Pathname.new("#{default_gemfile}.#{ruby}.lock")
-    end
-  end
-
-  # Add the Bundler.reset! method which has been added in master but is not in 1.7.9.
-  class << self
-    unless self.method_defined?("reset!")
-      def reset!
-        @definition = nil
-      end
-    end
-  end
-end

rakelib/dependency.rake

@@ -3,7 +3,7 @@ namespace "dependency" do
   task "bundler" do
     Rake::Task["gem:require"].invoke("bundler", ">= 1.3.5", LogStash::Environment.logstash_gem_home)
     require "bundler/cli"
-    require_relative "bundler_patch"
+    require "logstash/bundler_patch"
   end
 
   task "rbx-stdlib" do