Class: ReplRunner::PtyParty

Inherits:
Object
  • Object
show all
Defined in:
lib/repl_runner/pty_party.rb

Constant Summary collapse

TIMEOUT = 
1

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(command) ⇒ PtyParty

Returns a new instance of PtyParty.



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# File 'lib/repl_runner/pty_party.rb', line 6

def initialize(command)
  @output, @input, @pid = PTY.spawn(command)
end

Instance Attribute Details

#input ⇒ Object

Returns the value of attribute input.



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# File 'lib/repl_runner/pty_party.rb', line 3

def input
  @input
end

#output ⇒ Object

Returns the value of attribute output.



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# File 'lib/repl_runner/pty_party.rb', line 3

def output
  @output
end

#pid ⇒ Object

Returns the value of attribute pid.



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# File 'lib/repl_runner/pty_party.rb', line 3

def pid
  @pid
end

Instance Method Details

#close(timeout = TIMEOUT) ⇒ Object 



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# File 'lib/repl_runner/pty_party.rb', line 21

def close(timeout = TIMEOUT)
  Timeout::timeout(timeout) do
    input.close
    output.close
  end
rescue Timeout::Error
  # do nothing
ensure
  Process.kill('TERM', pid)   if pid.present?
end

#read(timeout = TIMEOUT, str = "") ⇒ Object

There be dragons - (You’re playing with process deadlock)

We want to read the whole output of the command First pull all contents from stdout (except we don’t know how many there are) So we have to go until our process deadlocks, then we timeout and return the string



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# File 'lib/repl_runner/pty_party.rb', line 38

def read(timeout = TIMEOUT, str = "")
  while true
    Timeout::timeout(timeout) do
      str << output.readline
      break if output.eof?
    end
  end

  return str
rescue Timeout::Error, EOFError, Errno::EIO
  return str
end

#run(cmd, timeout = TIMEOUT) ⇒ Object 



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# File 'lib/repl_runner/pty_party.rb', line 16

def run(cmd, timeout = TIMEOUT)
  write(cmd)
  return read(timeout)
end

#write(cmd) ⇒ Object 



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# File 'lib/repl_runner/pty_party.rb', line 10

def write(cmd)
  input.write(cmd)
rescue Errno::EIO => e
  raise e, "#{e.message} | trying to write '#{cmd}'"
end