Class: Ferrum::Page::Tracing

Inherits:

Object

• Object
• Ferrum::Page::Tracing

Defined in:

lib/ferrum/page/tracing.rb

Constant Summary

EXCLUDED_CATEGORIES =

%w[*].freeze

SCREENSHOT_CATEGORIES =

%w[disabled-by-default-devtools.screenshot].freeze

INCLUDED_CATEGORIES =

%w[devtools.timeline v8.execute disabled-by-default-devtools.timeline
disabled-by-default-devtools.timeline.frame toplevel blink.console
blink.user_timing latencyInfo disabled-by-default-devtools.timeline.stack
disabled-by-default-v8.cpu_profiler disabled-by-default-v8.cpu_profiler.hires].freeze

DEFAULT_TRACE_CONFIG =

{
  includedCategories: INCLUDED_CATEGORIES,
  excludedCategories: EXCLUDED_CATEGORIES
}.freeze

Instance Method Summary

• #initialize(page) ⇒ Tracing constructor

  A new instance of Tracing.

• #record(path: nil, encoding: :binary, timeout: nil, trace_config: nil, screenshots: false) ⇒ String, true

  Accepts block, records trace and by default returns trace data from Tracing.tracingComplete event as output.

Constructor Details

#initialize(page) ⇒ Tracing

Returns a new instance of Tracing.

# File 'lib/ferrum/page/tracing.rb', line 17

def initialize(page)
  @page = page
  @subscribed_tracing_complete = false
end

Instance Method Details

#record(path: nil, encoding: :binary, timeout: nil, trace_config: nil, screenshots: false) ⇒ String, true

Accepts block, records trace and by default returns trace data from Tracing.tracingComplete event as output.

Parameters:

• path (String, nil) (defaults to: nil) —

  Save data on the disk.

• encoding (:binary, :base64) (defaults to: :binary) —

  Encode output as Base64 or plain text.

• timeout (Float, nil) (defaults to: nil) —

  Wait until file streaming finishes in the specified time or raise error.

• screenshots (Boolean) (defaults to: false) —

  capture screenshots in the trace.

• trace_config (Hash{String => Object}) (defaults to: nil) —

  config for [trace](chromedevtools.github.io/devtools-protocol/tot/Tracing/#type-TraceConfig), for categories see [getCategories](chromedevtools.github.io/devtools-protocol/tot/Tracing/#method-getCategories), only one trace config can be active at a time per browser.

Returns:

• (String, true) —

  The trace data from the Tracing.tracingComplete event. When path is specified returns true and stores trace data into file.

# File 'lib/ferrum/page/tracing.rb', line 48

def record(path: nil, encoding: :binary, timeout: nil, trace_config: nil, screenshots: false)
  @path = path
  @encoding = encoding
  @pending = Concurrent::IVar.new
  trace_config ||= DEFAULT_TRACE_CONFIG.dup

  if screenshots
    included = trace_config.fetch(:includedCategories, [])
    trace_config.merge!(includedCategories: included | SCREENSHOT_CATEGORIES)
  end

  subscribe_tracing_complete

  start(trace_config)
  yield
  stop

  @pending.value!(timeout || @page.timeout)
end