# Home of the gems? **URL:** \ **Category:** ruby-talk\ **Created:** [9 December 2005 02:11 UTC](https://rubytalk.org/t/home-of-the-gems/23142 "2005-12-09T02:11:40Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Kelly\_Dwight\_Felkins](https://avatars.discourse-cdn.com/v4/letter/k/ecccb3/32.png) [@Kelly\_Dwight\_Felkins](https://rubytalk.org/u/Kelly_Dwight_Felkins)\ **Post date:** [9 December 2005 02:11 UTC](https://rubytalk.org/t/home-of-the-gems/23142/1 "2005-12-09T02:11:40Z")
I'm trying to understand how gems are loaded. Please help. A little background: I decided to do some rails development work on a debian system. I didn't think rails was up to date, so I tried to do a 'gem update rails'. This failed because I did not have root access. So I installed the gems locally. Everthing seemed fine. I later deleted the local gem directory. Now:    - "gem list" says there are no gems.    - "gemwhich rails" says "can't find rails.    - The application runs fine. By now it is clear to me that there are gems installed in the default location. I would like to override this with a local install. I don't understand how the load path is determined. Thanks for your help. -Kelly ---
**Author:** ![Jim\_Weirich1](https://avatars.discourse-cdn.com/v4/letter/j/73ab20/32.png) [@Jim\_Weirich1](https://rubytalk.org/u/Jim_Weirich1)\ **Post date:** [9 December 2005 04:52 UTC](https://rubytalk.org/t/home-of-the-gems/23142/2 "2005-12-09T04:52:26Z")
railsinator wrote: > I'm trying to understand how gems are loaded. Please help. > > A little background: > > I decided to do some rails development work on a debian system. I didn't > think rails was up to date, so I tried to do a 'gem update rails'. This > failed because I did not have root access. So I installed the gems > locally. > Everthing seemed fine. > > I later deleted the local gem directory. Now: > >    - "gem list" says there are no gems. >    - "gemwhich rails" says "can't find rails. >    - The application runs fine. > > By now it is clear to me that there are gems installed in the default > location. I would like to override this with a local install. I don't > understand how the load path is determined. > > Thanks for your help. 'gem env' will give you some information about your gem environment. You can control the details here via environment variables:    GEM\_HOME -- Path to gem repository where gems are installed by default.    GEM\_PATH -- List of paths of gem repositories to be searched. -- Jim Weirich > **···** > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Kelly\_Dwight\_Felkins](https://avatars.discourse-cdn.com/v4/letter/k/ecccb3/32.png) [@Kelly\_Dwight\_Felkins](https://rubytalk.org/u/Kelly_Dwight_Felkins)\ **Post date:** [9 December 2005 18:03 UTC](https://rubytalk.org/t/home-of-the-gems/23142/3 "2005-12-09T18:03:33Z")
Thanks for getting back to me Jim. Please bear with me as I try to understand how this works. If I do "gem env" I get a stack trace: kfelkins@lurch:~/bin$ gem env /usr/local/lib/site\_ruby/1.8/rubygems.rb:194:in `report\_activate\_error': Could not find RubyGem sources (\> 0.0.0) (Gem::LoadError)     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:136:in `activate'     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:37:in `require\_gem\_with\_options'     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:31:in `require\_gem'     from /usr/local/lib/site\_ruby/1.8/rubygems/remote\_installer.rb:403:in `sources'     from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_commands.rb:897:in `execute'     from /usr/local/lib/site\_ruby/1.8/rubygems/command.rb:49:in `invoke'     from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:92:in `process\_args'     from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:65:in `run'     from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_runner.rb:9:in `run'     from /home/kfelkins/bin/gem:17 kfelkins@lurch:~/bin$ Still, my rails app will run when I start it with script/server. So clearly there are a set of gems installed somewhere. These were likely installed via the debian package management system. So how are gems found? kfelkins@lurch:~/bin$ echo $GEM\_HOME /home/kfelkins/gem-repository kfelkins@lurch:~/bin$ ls -l $GEM\_HOME total 16 drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 cache drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 doc drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 gems drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 specifications kfelkins@lurch:~/bin$ cd $GEM\_HOME/gems kfelkins@lurch:~/gem-repository/gems$ ls kfelkins@lurch:~/gem-repository/gems$ echo $GEM\_PATH kfelkins@lurch:~/gem-repository/gems$ Thanks again. -Kelly > **···** > > On 12/8/05, Jim Weirich \ wrote: > > > railsinator wrote: > > \> I'm trying to understand how gems are loaded. Please help. > > \> > > \> A little background: > > \> > > \> I decided to do some rails development work on a debian system. I didn't > > \> think rails was up to date, so I tried to do a 'gem update rails'. This > > \> failed because I did not have root access. So I installed the gems > > \> locally. > > \> Everthing seemed fine. > > \> > > \> I later deleted the local gem directory. Now: > > \> > > \> - "gem list" says there are no gems. > > \> - "gemwhich rails" says "can't find rails. > > \> - The application runs fine. > > \> > > \> By now it is clear to me that there are gems installed in the default > > \> location. I would like to override this with a local install. I don't > > \> understand how the load path is determined. > > \> > > \> Thanks for your help. > > > > 'gem env' will give you some information about your gem environment. > > You can control the details here via environment variables: > > > >    GEM\_HOME -- Path to gem repository where gems are installed by > > default. > >    GEM\_PATH -- List of paths of gem repositories to be searched. > > > > -- Jim Weirich > > > > -- > > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Jim\_Weirich1](https://avatars.discourse-cdn.com/v4/letter/j/73ab20/32.png) [@Jim\_Weirich1](https://rubytalk.org/u/Jim_Weirich1)\ **Post date:** [9 December 2005 18:53 UTC](https://rubytalk.org/t/home-of-the-gems/23142/4 "2005-12-09T18:53:13Z")
railsinator wrote: > Thanks for getting back to me Jim. Please bear with me as I try to > understand how this works. > > If I do "gem env" I get a stack trace: > > kfelkins@lurch:~/bin$ gem env > /usr/local/lib/site\_ruby/1.8/rubygems.rb:194:in `report\_activate\_error': > Could not find RubyGem sources (\> 0.0.0) (Gem::LoadError) >     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:136:in `activate' >     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:37:in > `require\_gem\_with\_options' >     from /usr/local/lib/site\_ruby/1.8/rubygems.rb:31:in `require\_gem' >     from > /usr/local/lib/site\_ruby/1.8/rubygems/remote\_installer.rb:403:in > `sources' >     from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_commands.rb:897:in > `execute' >     from /usr/local/lib/site\_ruby/1.8/rubygems/command.rb:49:in `invoke' >     from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:92:in > `process\_args' >     from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:65:in > `run' >     from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_runner.rb:9:in `run' >     from /home/kfelkins/bin/gem:17 > kfelkins@lurch:~/bin$ > > Still, my rails app will run when I start it with script/server. > > So clearly there are a set of gems installed somewhere. These were > likely > installed via the debian package management system. So how are gems > found? > > kfelkins@lurch:~/bin$ echo $GEM\_HOME > /home/kfelkins/gem-repository > kfelkins@lurch:~/bin$ ls -l $GEM\_HOME > total 16 > drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 cache > drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 doc > drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 gems > drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 specifications > kfelkins@lurch:~/bin$ cd $GEM\_HOME/gems > kfelkins@lurch:~/gem-repository/gems$ ls > kfelkins@lurch:~/gem-repository/gems$ echo $GEM\_PATH > kfelkins@lurch:~/gem-repository/gems$ Ok, it looks like you no longer have the system gem repository in your GEM\_PATH. Gem can't find its sources gem. Try adding the original repository to the GEM\_PATH. Perhaps something like this:    export GEM\_PATH=/usr/local/lib/ruby/gems/1.8 (you might need to tweek the directory for your local system). Once you add that line, gems should search both your $GEM\_HOME repository and the GEM\_PATH repository. You can add more repositories to GEM\_PATH if you wish. -- Jim Weirich > **···** > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Kelly\_Dwight\_Felkins](https://avatars.discourse-cdn.com/v4/letter/k/ecccb3/32.png) [@Kelly\_Dwight\_Felkins](https://rubytalk.org/u/Kelly_Dwight_Felkins)\ **Post date:** [9 December 2005 19:02 UTC](https://rubytalk.org/t/home-of-the-gems/23142/5 "2005-12-09T19:02:52Z")
I think rails can find the gems. Do you know how rails does it? I'm not certain that rails uses gems \*after\* an application has been created. Rails is installed as a collection of gems, but I guess it is possible that when you create a rails application all of the required libraries are copied or linked, though I doubt it. -kelly > **···** > > On 12/9/05, Jim Weirich \ wrote: > > > railsinator wrote: > > \> Thanks for getting back to me Jim. Please bear with me as I try to > > \> understand how this works. > > \> > > \> If I do "gem env" I get a stack trace: > > \> > > \> kfelkins@lurch:~/bin$ gem env > > \> /usr/local/lib/site\_ruby/1.8/rubygems.rb:194:in `report\_activate\_error': > > \> Could not find RubyGem sources (\> 0.0.0) (Gem::LoadError) > > \> from /usr/local/lib/site\_ruby/1.8/rubygems.rb:136:in `activate' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems.rb:37:in > > \> `require\_gem\_with\_options' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems.rb:31:in `require\_gem' > > \> from > > \> /usr/local/lib/site\_ruby/1.8/rubygems/remote\_installer.rb:403:in > > \> `sources' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_commands.rb:897:in > > \> `execute' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems/command.rb:49:in `invoke' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:92:in > > \> `process\_args' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems/cmd\_manager.rb:65:in > > \> `run' > > \> from /usr/local/lib/site\_ruby/1.8/rubygems/gem\_runner.rb:9:in `run' > > \> from /home/kfelkins/bin/gem:17 > > \> kfelkins@lurch:~/bin$ > > \> > > \> Still, my rails app will run when I start it with script/server. > > \> > > \> So clearly there are a set of gems installed somewhere. These were > > \> likely > > \> installed via the debian package management system. So how are gems > > \> found? > > \> > > \> kfelkins@lurch:~/bin$ echo $GEM\_HOME > > \> /home/kfelkins/gem-repository > > \> kfelkins@lurch:~/bin$ ls -l $GEM\_HOME > > \> total 16 > > \> drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 cache > > \> drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 doc > > \> drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 gems > > \> drwxrwxr-x 2 kfelkins genome 4096 2005-12-08 17:15 specifications > > \> kfelkins@lurch:~/bin$ cd $GEM\_HOME/gems > > \> kfelkins@lurch:~/gem-repository/gems$ ls > > \> kfelkins@lurch:~/gem-repository/gems$ echo $GEM\_PATH > > \> kfelkins@lurch:~/gem-repository/gems$ > > > > Ok, it looks like you no longer have the system gem repository in your > > GEM\_PATH. Gem can't find its sources gem. > > > > Try adding the original repository to the GEM\_PATH. Perhaps something > > like this: > > > >    export GEM\_PATH=/usr/local/lib/ruby/gems/1.8 > > > > (you might need to tweek the directory for your local system). > > > > Once you add that line, gems should search both your $GEM\_HOME > > repository and the GEM\_PATH repository. You can add more repositories > > to GEM\_PATH if you wish. > > > > -- Jim Weirich > > > > -- > > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Jim\_Weirich1](https://avatars.discourse-cdn.com/v4/letter/j/73ab20/32.png) [@Jim\_Weirich1](https://rubytalk.org/u/Jim_Weirich1)\ **Post date:** [9 December 2005 19:50 UTC](https://rubytalk.org/t/home-of-the-gems/23142/6 "2005-12-09T19:50:38Z")
railsinator wrote: > I think rails can find the gems. Do you know how rails does it? > > I'm not certain that rails uses gems \*after\* an application has been > created. Rails is installed as a collection of gems, but I guess it is > possible that when you create a rails application all of the required > libraries are copied or linked, though I doubt it. hard to say without knowing more details. Some possibilities are: (1) Rails comes in non-gem versions, is one of those installed? (2) GEM\_HOME is an environment variable. Although your interactive shell was messed up, it could be that rails is running in a different window with its own, properly setup, GEM\_HOME value. (Possibly started before you changed it). -- Jim Weirich > **···** > > -- > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C). ---
**Author:** ![Kelly\_Dwight\_Felkins](https://avatars.discourse-cdn.com/v4/letter/k/ecccb3/32.png) [@Kelly\_Dwight\_Felkins](https://rubytalk.org/u/Kelly_Dwight_Felkins)\ **Post date:** [9 December 2005 20:24 UTC](https://rubytalk.org/t/home-of-the-gems/23142/7 "2005-12-09T20:24:51Z")
Thanks Jim. I'm going to go with your #1. Since this is a debian system, my guess is rails was installed using apt-get. I also run debian on my personal systems but I don't use apt-get to install rails -- I use gems. -Kelly > **···** > > On 12/9/05, Jim Weirich \ wrote: > > > railsinator wrote: > > \> I think rails can find the gems. Do you know how rails does it? > > \> > > \> I'm not certain that rails uses gems \*after\* an application has been > > \> created. Rails is installed as a collection of gems, but I guess it is > > \> possible that when you create a rails application all of the required > > \> libraries are copied or linked, though I doubt it. > > > > hard to say without knowing more details. Some possibilities are: > > > > (1) Rails comes in non-gem versions, is one of those installed? > > (2) GEM\_HOME is an environment variable. Although your interactive > > shell was messed up, it could be that rails is running in a different > > window with its own, properly setup, GEM\_HOME value. (Possibly started > > before you changed it). > > > > -- Jim Weirich > > > > -- > > Posted via [http://www.ruby-forum.com/\](http://www.ruby-forum.com/%5C).