Posted over 4 years ago. Visible to the public.

Fix Capistrano with RubyGems 1.6

After updating your RubyGems, you will probably not be able to run Capistrano any more, but receive an error similar to this:
can't activate net-ssh (= 2.0.22) for [], already activated net-ssh-2.1.0 for [] (Gem::LoadError)

If you have Bundler installed, you can use bundle exec to avoid this problem as follows:

Create a gemfile at ~/.capistrano/Gemfile (or at some other sensible place), that only contains these 2 lines:
source 'http://rubygems.org'
gem 'capistrano'
gem 'capistrano-ext' # You need this for multistage deployments
gem 'hoptoad_notifier' # Add this for projects that use Hoptoad and Capistrano integration

Run bundle install in the same directory.

Now you can use Capistrano again by prepending BUNDLE_GEMFILE=~/.capistrano/Gemfile bundle exec, i.e.
BUNDLE_GEMFILE=~/.capistrano/Gemfile bundle exec cap deploy

I suggest making a shell alias. For the Bash, append this to your ~/.bashrc:
alias cap='BUNDLE_GEMFILE=~/.capistrano/Gemfile bundle exec cap'

Now you can once again simply run cap deploy.

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Author of this card:

Avatar
Tobias Kraze
Keywords:
netssh, ruby, deployment, conflict
About this deck:
We are makandra and do test-driven, agile Ruby on Rails software development.
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All source code included in the card Fix Capistrano with RubyGems 1.6 is licensed under the license stated below. This includes both code snippets embedded in the card text and code that is included as a file attachment. Excepted from this license are code snippets that are explicitely marked as citations from another source.

The MIT License (MIT)

Copyright (c) 2011-2012 makandra GmbH

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Posted by Tobias Kraze to makandropedia