Module: Palapala::ChromeProcess

Defined in:
lib/palapala/chrome_process.rb

Overview

Manage the Chrome child process

Class Method Summary collapse

Class Method Details

.chrome_path ⇒ Object

Get the path to the Chrome executable, if it’s not set, then guess based on the OS



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# File 'lib/palapala/chrome_process.rb', line 43

def self.chrome_path
  return Palapala.headless_chrome_path if Palapala.headless_chrome_path

  case RbConfig::CONFIG["host_os"]
  when /darwin/
    "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"
  when /linux/
    "/usr/bin/google-chrome" # or "/usr/bin/chromium-browser"
  when /win|mingw|cygwin/
    "#{ENV.fetch("ProgramFiles(x86)", nil)}\\Google\\Chrome\\Application\\chrome.exe"
  else
    raise "Unsupported OS"
  end
end

.chrome_process_healthy? ⇒ Boolean

Check if the Chrome process is healthy

Returns:

  • (Boolean) 


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# File 'lib/palapala/chrome_process.rb', line 17

def self.chrome_process_healthy?
  return false if @chrome_process_id.nil?

  begin
    Process.kill(0, @chrome_process_id) # Check if the process is alive
    true
  rescue Errno::ESRCH, Errno::EPERM
    false
  end
end

.chrome_running? ⇒ Boolean

Check if a Chrome is running

Returns:

  • (Boolean) 


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# File 'lib/palapala/chrome_process.rb', line 29

def self.chrome_running?
  port_in_use? || # Check if the port is in use and Chrome is running externally
  chrome_process_healthy? # Check if the process is still alive
end

.kill_chrome ⇒ Object

Kill the Chrome child process



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# File 'lib/palapala/chrome_process.rb', line 35

def self.kill_chrome
  return if @chrome_process_id.nil?

  Process.kill("KILL", @chrome_process_id) # Kill the process
  Process.wait(@chrome_process_id) # Wait for the process to finish
end

.npx_installed? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/palapala/chrome_process.rb', line 58

def self.npx_installed?
  system("which npx > /dev/null 2>&1")
end

.port_in_use?(port = 9222, host = "127.0.0.1") ⇒ Boolean

Check if the port is in use

Returns:

  • (Boolean) 


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# File 'lib/palapala/chrome_process.rb', line 8

def self.port_in_use?(port = 9222, host = "127.0.0.1")
  server = TCPServer.new(host, port)
  server.close
  false
rescue Errno::EADDRINUSE
  true
end

.spawn_chrome ⇒ Object

Spawn a Chrome child process



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# File 'lib/palapala/chrome_process.rb', line 97

def self.spawn_chrome
  return if chrome_running?

  if self.npx_installed?
    @chrome_process_id = spawn_chrome_headless_server
  else
    params = [ "--headless", "--disable-gpu", "--remote-debugging-port=9222" ]
    params.merge!(Palapala.chrome_params) if Palapala.chrome_params
    # Spawn an existing chrome with the path and parameters
    @chrome_process_id = Process.spawn(chrome_path, *params)
  end

  # Wait until the port is in use
  sleep 0.1 until port_in_use?
  # Detach the process so it runs in the background
  Process.detach(@chrome_process_id)

  at_exit do
    if @chrome_process_id
      begin
        Process.kill("TERM", @chrome_process_id)
        Process.wait(@chrome_process_id)
        puts "Child process #{@chrome_process_id} terminated."
      rescue Errno::ESRCH
        puts "Child process #{@chrome_process_id} is already terminated."
      rescue Errno::ECHILD
        puts "No child process #{@chrome_process_id} found."
      end
    end
  end

  # Handle when the process is killed
  trap("SIGCHLD") do
    while (@chrome_process_id = Process.wait(-1, Process::WNOHANG))
      break if @chrome_process_id.nil?

      puts "Process #{@chrome_process_id} was killed."
      # Handle the error or restart the process if necessary
      @chrome_process_id = nil
    end
  rescue Errno::ECHILD
    @chrome_process_id = nil
  end
end

.spawn_chrome_headless_server ⇒ Object 



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# File 'lib/palapala/chrome_process.rb', line 62

def self.spawn_chrome_headless_server
  # Run the command and capture the output
  puts "Installing latest stable chrome-headless-shell..."
  output, status = Open3.capture2("npx --yes @puppeteer/browsers install chrome-headless-shell@#{Palapala.chrome_headless_shell_version}")

  if status.success?
    # Extract the path from the output
    result = output.lines.find { |line| line.include?("chrome-headless-shell@") }
    if result.nil?
      raise "Failed to install chrome-headless-shell"
    end
    _, chrome_path = result.split(" ", 2).map(&:strip)

    # Directory you want the relative path from (current working directory)
    base_dir = Dir.pwd

    # Convert absolute path to relative path
    relative_path = Pathname.new(chrome_path).relative_path_from(Pathname.new(base_dir)).to_s

    puts "Launching chrome-headless-shell at #{relative_path}" if Palapala.debug
    # Display the version
    system("#{chrome_path} --version") if Palapala.debug
    # Launch chrome-headless-shell with the --remote-debugging-port parameter
    if Palapala.debug
      puts "spawning with output"
      spawn(chrome_path, "--remote-debugging-port=9222", "--disable-gpu")
    else
      spawn(chrome_path, "--remote-debugging-port=9222", "--disable-gpu", out: "/dev/null", err: "/dev/null")
    end
  else
    raise "Failed to install chrome-headless-shell"
  end
end