Adds another layer on top of Net::SSH for a proper handling of CLI sessions which last longer than one command. This is especially usefull for enterprise Switches and Routers.
Add this line to your application's Gemfile:
gem 'net-ssh-cli'
And then execute:
$ bundle
Or install it yourself as:
$ gem install net-ssh-cli
- provides an abstraction on top of the text-stream of a long living CLI sessions
- tries to be highly configurable
- has methods like #cmd and #dialog for common usecases
- offers waiting operations like #read_till
Net::SSH.start('host', 'user', password: "password") do |ssh| cli = ssh.cli(default_prompt: /(\nuser@host):/m) cli.cmd "" # => "Last login: \nuser@host:" cli.cmd "echo 'bananas'" # => "echo 'bananas'\nbananas\nuser@host:" end
net_ssh = Net::SSH.start('host', 'user', password: "password") cli = Net::SSH::CLI::Session.new(net_ssh: net_ssh) cli.cmd ""
cli = Net::SSH::CLI::Session.new(net_ssh_options: {host: 'host', user: 'user', password: 'password'}) cli.cmd ""
cli = ssh.cli(default_prompt: /(\nuser@host):/m) cli.cmd "echo 'bananas'" # => "echo 'bananas'\nbananas\nuser@host:" cli.cmd "echo 'bananas'", rm_command: true # => "bananas\nuser@host:" cli.cmd "echo 'bananas'", rm_prompt: true # => "echo 'bananas'\nbananas" cli.cmd "echo 'bananas'", rm_command: true, rm_prompt: true # => "bananas"
Remove the command and the prompt for #cmd & #dialog by default
cli = ssh.cli(default_prompt: /(\nuser@host):/m, cmd_rm_command: true, cmd_rm_prompt: true) cli.cmd "echo 'bananas'" # => "bananas"
It's the same as #cmd but for multiple commands.
cli.cmds ["echo 'bananas'", "echo 'apples'"], rm_command: true, rm_prompt: true # => ["bananas", "apples"]
Use this method to specify a differnt 'prompt' for once. This is perfect for interactive commands.
cli.dialog "echo 'are you sure?' && read -p 'yes|no>'", /\nyes|no>/ # => "echo 'are you sure?' && read -p 'yes|no>'\nyes|no>" cli.cmd "yes"
cli.dialog "passwd", /Current Password:/i cli.dialog "Old Password", /New Password:/i cli.dialog "New Password", /Repeat Password:/i cli.cmd "New Password"
The very same as #cmd but it respects a flag whether to run commands with 'impact'.
This can be used in a setup where you don't want to run certain commands under certain conditions.
For example in testing.
cli.run_impact? # => false cli.impact "reboot now" # => "skip: 'reboot now'"
cli.run_impact = true cli.impact "reboot now" # => connection closed
cli.write "echo 'hello'\n" # => "echo 'hello'\n" cli.read # => "echo 'hello'\nhello\nuser@host:"
cli.write_n "echo 'hello'" # => "echo 'hello'\n"
keep on processing till the stdout matches to given|default prompt and then read the whole stdin.
cli.write "echo 'hello'\n" # => "echo 'hello'\n" cli.read_till # => "echo 'hello'\nhello\nuser@host:"
This method is used by #cmd, see lib/net/ssh/cli.rb#cmd
cli.write_n "sleep 180" # => "" cli.read_for(seconds: 181) # => "..."
Have a deep look at the various Options configured by Net::SSH::CLI::OPTIONS in lib/net/ssh/cli.rb
Nearly everything can be configured.
The following callbacks are available
- before_open_channel
- after_open_channel
- before_on_stdout
- after_on_stdout
cli.before_open_channel do puts "The channel will open soon" end
cli.after_open_channel do cmd "logger 'Net::SSH::CLI works'" cmd "sudo -i" end
Using the callbacks you can define a debugger which shows the stdout buffer content each time new data is received.
cli.after_on_stdout do warn stdout end
cli.after_on_stdout do stdout.gsub!("\r\n", "\n") end
cli.to_s # => "localhost" cli.hostname # => "localhost" cli.host # => "localhost"
NET::SSH::CLI can try to guess the prompt by waiting for it and using the last line. This works usually, but is not guaranteed to work well.
cli.open_channel # => ... cli.detect_prompt(seconds: 3) # => "[my prompt]"
After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/swisscom/net-ssh-cli.
The gem is available as open source under the terms of the MIT License.