Class: Ferrum::Browser::Xvfb

Inherits:
Object
  • Object
show all
Defined in:
lib/ferrum/browser/xvfb.rb

Overview

Manages an Xvfb virtual display server, letting a "headful" browser run in environments without a real display (e.g. CI). Spawned by Process when the :xvfb option is set, and exposes the DISPLAY environment variable the browser process needs to attach to it.

Constant Summary collapse

NOT_FOUND = 
"Could not find an executable for the Xvfb. Try to install " \
"it with your package manager"

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options) ⇒ Xvfb

Returns a new instance of Xvfb.

Raises:



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# File 'lib/ferrum/browser/xvfb.rb', line 29

def initialize(options)
  @path = Binary.find("Xvfb")
  raise BinaryNotFoundError, NOT_FOUND unless @path

  @screen_size = "#{options.window_size.join('x')}x24"
  @display_id = (Time.now.to_f * 1000).to_i % 100_000_000
end

Instance Attribute Details

#display_id ⇒ Object (readonly)

Returns the value of attribute display_id.



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# File 'lib/ferrum/browser/xvfb.rb', line 27

def display_id
  @display_id
end

#pid ⇒ Object (readonly)

Returns the value of attribute pid.



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# File 'lib/ferrum/browser/xvfb.rb', line 27

def pid
  @pid
end

#screen_size ⇒ Object (readonly)

Returns the value of attribute screen_size.



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# File 'lib/ferrum/browser/xvfb.rb', line 27

def screen_size
  @screen_size
end

Class Method Details

.start(*args) ⇒ Xvfb

Builds and starts a new Xvfb instance.

Parameters:

Returns:



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# File 'lib/ferrum/browser/xvfb.rb', line 23

def self.start(*args)
  new(*args).tap(&:start)
end

Instance Method Details

#start ⇒ void

This method returns an undefined value.

Spawns the Xvfb process on the configured display.



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# File 'lib/ferrum/browser/xvfb.rb', line 42

def start
  @pid = ::Process.spawn("#{@path} :#{display_id} -screen 0 #{screen_size}")
  ::Process.detach(@pid)
end

#to_env ⇒ Hash{String => String}

Environment variables needed to point the browser at this Xvfb display.

Returns:

  • (Hash{String => String}) 


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# File 'lib/ferrum/browser/xvfb.rb', line 52

def to_env
  { "DISPLAY" => ":#{display_id}" }
end