module Dev::Kit::System
Constants
- SUDO_PROMPT
Public Class Methods
Execute a command in the user's environment This is meant to be largely equivalent to backticks, only with the env passed in. Captures the results of the command without output to the console
#### Parameters
-
`*a`: A splat of arguments evaluated as a command. (e.g. `'rm', folder` is equivalent to `rm #{folder}`)
-
`sudo`: If truthy, run this command with sudo. If String, pass to `sudo_reason`
-
`env`: process environment with which to execute this command
-
`**kwargs`: additional arguments to pass to Open3.capture2
#### Returns
-
`output`: output (STDOUT) of the command execution
-
`status`: boolean success status of the command execution
#### Usage `out, stat = Dev::Kit::System.capture2
('ls', 'a_folder')`
# File lib/dev/kit/system.rb, line 47 def capture2(*a, sudo: false, env: ENV, **kwargs) delegate_open3(*a, sudo: sudo, env: env, method: :capture2, **kwargs) end
Execute a command in the user's environment This is meant to be largely equivalent to backticks, only with the env passed in. Captures the results of the command without output to the console
#### Parameters
-
`*a`: A splat of arguments evaluated as a command. (e.g. `'rm', folder` is equivalent to `rm #{folder}`)
-
`sudo`: If truthy, run this command with sudo. If String, pass to `sudo_reason`
-
`env`: process environment with which to execute this command
-
`**kwargs`: additional arguments to pass to Open3.capture2e
#### Returns
-
`output`: output (STDOUT merged with STDERR) of the command execution
-
`status`: boolean success status of the command execution
#### Usage `out_and_err, stat = Dev::Kit::System.capture2e
('ls', 'a_folder')`
# File lib/dev/kit/system.rb, line 68 def capture2e(*a, sudo: false, env: ENV, **kwargs) delegate_open3(*a, sudo: sudo, env: env, method: :capture2e, **kwargs) end
Execute a command in the user's environment This is meant to be largely equivalent to backticks, only with the env passed in. Captures the results of the command without output to the console
#### Parameters
-
`*a`: A splat of arguments evaluated as a command. (e.g. `'rm', folder` is equivalent to `rm #{folder}`)
-
`sudo`: If truthy, run this command with sudo. If String, pass to `sudo_reason`
-
`env`: process environment with which to execute this command
-
`**kwargs`: additional arguments to pass to Open3.capture3
#### Returns
-
`output`: STDOUT of the command execution
-
`error`: STDERR of the command execution
-
`status`: boolean success status of the command execution
#### Usage `out, err, stat = Dev::Kit::System.capture3
('ls', 'a_folder')`
# File lib/dev/kit/system.rb, line 90 def capture3(*a, sudo: false, env: ENV, **kwargs) delegate_open3(*a, sudo: sudo, env: env, method: :capture3, **kwargs) end
Ask for sudo access with a message explaning the need for it Will make subsequent commands capable of running with sudo for a period of time
#### Parameters
-
`msg`: A message telling the user why sudo is needed
#### Usage `ctx.sudo_reason(“We need to do a thing”)`
# File lib/dev/kit/system.rb, line 21 def sudo_reason(msg) # See if sudo has a cached password `env SUDO_ASKPASS=/usr/bin/false sudo -A true` return if $CHILD_STATUS.success? Dev::UI.with_frame_color(:blue) do puts(Dev::UI.fmt("{{i}} #{msg}")) end end
Execute a command in the user's environment Outputs result of the command without capturing it
#### Parameters
-
`*a`: A splat of arguments evaluated as a command. (e.g. `'rm', folder` is equivalent to `rm #{folder}`)
-
`sudo`: If truthy, run this command with sudo. If String, pass to `sudo_reason`
-
`env`: process environment with which to execute this command
-
`**kwargs`: additional keyword arguments to pass to Process.spawn
#### Returns
-
`status`: boolean success status of the command execution
#### Usage `stat = Dev::Kit::System.system
('ls', 'a_folder')`
# File lib/dev/kit/system.rb, line 109 def system(*a, sudo: false, env: ENV, **kwargs) a = apply_sudo(*a, sudo) out_r, out_w = IO.pipe err_r, err_w = IO.pipe in_stream = STDIN.closed? ? :close : STDIN pid = Process.spawn(env, *resolve_path(a, env), 0 => in_stream, :out => out_w, :err => err_w, **kwargs) out_w.close err_w.close handlers = if block_given? { out_r => ->(data) { yield(data.force_encoding(Encoding::UTF_8), '') }, err_r => ->(data) { yield('', data.force_encoding(Encoding::UTF_8)) }, } else { out_r => ->(data) { STDOUT.write(data) }, err_r => ->(data) { STDOUT.write(data) }, } end loop do ios = [err_r, out_r].reject(&:closed?) break if ios.empty? readers, = IO.select(ios) readers.each do |io| begin handlers[io].call(io.readpartial(4096)) rescue IOError io.close end end end Process.wait(pid) $CHILD_STATUS end
Private Class Methods
# File lib/dev/kit/system.rb, line 147 def apply_sudo(*a, sudo) a.unshift('sudo', '-S', '-p', SUDO_PROMPT, '--') if sudo sudo_reason(sudo) if sudo.is_a?(String) a end
# File lib/dev/kit/system.rb, line 153 def delegate_open3(*a, sudo: raise, env: raise, method: raise, **kwargs) a = apply_sudo(*a, sudo) Open3.send(method, env, *resolve_path(a, env), **kwargs) rescue Errno::EINTR raise(Errno::EINTR, "command interrupted: #{a.join(' ')}") end
Ruby resolves the program to execute using its own PATH, but we want it to use the provided one, so we ensure ruby chooses to spawn a shell, which will parse our command and properly spawn our target using the provided environment.
This is important because dev clobbers its own environment such that ruby means /usr/bin/ruby, but we want it to select the ruby targeted by the active project.
See github.com/Shopify/dev/pull/625 for more details.
# File lib/dev/kit/system.rb, line 169 def resolve_path(a, env) # If only one argument was provided, make sure it's interpreted by a shell. return ["true ; " + a[0]] if a.size == 1 return a if a.first.include?('/') item = env.fetch('PATH', '').split(':').detect do |f| File.exist?("#{f}/#{a.first}") end a[0] = "#{item}/#{a.first}" if item a end