Greetings,
I'm wondering if anyone has used Capistrano to automate the
installation of gems on remote machines.
The problem I'm having is that when you install a gem from the
command line, at various stages it will prompt you for a 'Y' or 'N'
answer.
Let's say I have the following task and I want it to run on a remote
machine:
desc "Install rails"
task :install_rails do
run "gem install rails"
end
The task starts up and begins the installation, but then hangs after
I get the 'Y' or 'N' prompt.
Is there a way to just skip the prompt and specify 'Y' for everything?
Regards,
Steven
Hey Steven-
Here is a capistrano plugin for installing gems remotely. This
supports slecting gem versions or letting it pick from the list itself
when it gets presented with a list of choices it will choose the
correct latest version based on architecture.
This is code adapted and extracted from the vmgen gem for
generating Xen instances.
require 'capistrano'
# Installs within Capistrano as the plugin _gem_.
# Prefix all calls to the library with <tt>gem.</tt>
# Manages installing gems and versioned gems.
module Gem
# Default install command
#
# * doesn't install documentation
# * installs all required dependencies automatically.
#
GEM_INSTALL="gem install -y --no-rdoc"
# Upgrade the *gem* system to the latest version. Runs via *sudo*
def update_system
sudo "gem update --system"
end
# Updates all the installed gems to the latest version. Runs via
*sudo*.
# Don't use this command if any of the gems require a version
selection.
def upgrade
sudo "gem update --no-rdoc"
end
# Removes old versions of gems from installation area.
def cleanup
sudo "gem cleanup"
end
# Installs the gems detailed in +packages+, selecting version
+version+ if
# specified.
#
# +packages+ can be a single string or an array of strings.
#
def install(packages, version=nil)
sudo "#{GEM_INSTALL} #{if version then '-v '+version.to_s end}
#{packages.to_a.join(' ')}"
end
# Auto selects a gem from a list and installs it.
#
# *gem* has no mechanism on the command line of disambiguating
builds for
# different platforms, and instead asks the user. This method has
the necessary
# conversation to select the +version+ relevant to +platform+ (or
the one nearest
# the top of the list if you don't specify +version+).
def select(package, version=nil, platform='ruby')
selections={}
cmd="#{GEM_INSTALL} #{if version then '-v '+version.to_s end}
#{package}"
sudo cmd do |channel, stream, data|
data.each_line do | line |
case line
when /\s(\d+).*\(#{platform}\)/
if selections[channel[:host]].nil?
selections[channel[:host]]=$1.dup+"\n"
logger.info "Selecting #$&", "#{stream} :: #{channel[:host]}"
end
when /\s\d+\./
# Discard other selections from data stream
when /^>/
channel.send_data selections[channel[:host]]
logger.debug line, "#{stream} :: #{channel[:host]}"
else
logger.info line, "#{stream} :: #{channel[:host]}"
end
end
end
end
end
Capistrano.plugin :gem, Gem
Cheers-
-- Ezra Zygmuntowicz-- Lead Rails Evangelist
-- (e-mail address removed)
-- Engine Yard, Serious Rails Hosting
-- (866) 518-YARD (9273)
