ferrum

Headless Chrome Ruby API

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Ruby

Ferrum - high-level API to control Chrome in Ruby

As simple as Puppeteer, though even simpler.

It is Ruby clean and high-level API to Chrome. Runs headless by default, but you
can configure it to run in a headful mode. All you need is Ruby and
Chrome or
Chromium. Ferrum connects to the browser by CDP
protocol and there’s no
Selenium/WebDriver/ChromeDriver dependency. The emphasis was made on a raw CDP
protocol because Chrome allows you to do so many things that are barely
supported by WebDriver because it should have consistent design with other
browsers.

Cuprite is a pure Ruby driver for
Capybara based on Ferrum. If you are
going to crawl sites you better use Ferrum or
Vessel because you crawl, not test.
Vessel high-level web crawling framework
based on Ferrum and Mechanize.

Index

Install

There’s no official Chrome or Chromium package for Linux don’t install it this
way because it’s either outdated or unofficial, both are bad. Download it from
official source for Chrome or
Chromium.
Chrome binary should be in the PATH or BROWSER_PATH and you can pass it as an
option to browser instance see :browser_path in
Customization.

Add this to your Gemfile and run bundle install.

gem "ferrum"

Examples

Navigate to a website and save a screenshot:

browser = Ferrum::Browser.new
browser.go_to("https://google.com")
browser.screenshot(path: "google.png")
browser.quit

When you work with browser instance Ferrum creates and maintains a default page for you, in fact all the methods above
are sent to the page instance that is created in the default_context of the browser instance. You can interact
with a page created manually and this is preferred:

browser = Ferrum::Browser.new
page = browser.create_page
page.go_to("https://google.com")
input = page.at_xpath("//input[@name='q']")
input.focus.type("Ruby headless driver for Chrome", :Enter)
page.at_css("a > h3").text # => "rubycdp/ferrum: Ruby Chrome/Chromium driver - GitHub"
browser.quit

Evaluate some JavaScript and get full width/height:

browser = Ferrum::Browser.new
page = browser.create_page
page.go_to("https://www.google.com/search?q=Ruby+headless+driver+for+Capybara")
width, height = page.evaluate <<~JS
  [document.documentElement.offsetWidth,
   document.documentElement.offsetHeight]
JS
# => [1024, 1931]
browser.quit

Do any mouse movements you like:

# Trace a 100x100 square
browser = Ferrum::Browser.new
page = browser.create_page
page.go_to("https://google.com")
page.mouse
  .move(x: 0, y: 0)
  .down
  .move(x: 0, y: 100)
  .move(x: 100, y: 100)
  .move(x: 100, y: 0)
  .move(x: 0, y: 0)
  .up

browser.quit

Docker

In docker as root you must pass the no-sandbox browser option:

Ferrum::Browser.new(browser_options: { 'no-sandbox': nil })

It has also been reported that the Chrome process repeatedly crashes when running inside a Docker container on an M1 Mac preventing Ferrum from working. Ferrum should work as expected when deployed to a Docker container on a non-M1 Mac.

Customization

You can customize options with the following code in your test setup:

Ferrum::Browser.new(options)

options Hash
- :headless (String | Boolean) - Set browser as headless or not, true by default. You can set "new" to support
  new headless mode.
- :xvfb (Boolean) - Run browser in a virtual framebuffer, false by default.
- :flatten (Boolean) - Use one websocket connection to the browser and all the pages in flatten mode.
- :window_size (Array) - The dimensions of the browser window in which to
  test, expressed as a 2-element array, e.g. [1024, 768]. Default: [1024, 768]
- :extensions (Array[String | Hash]) - An array of paths to files or JS
  source code to be preloaded into the browser e.g.:
  ["/path/to/script.js", { source: "window.secret = 'top'" }]
- :logger (Object responding to puts) - When present, debug output is
  written to this object.
- :slowmo (Integer | Float) - Set a delay in seconds to wait before sending command.
  Useful companion of headless option, so that you have time to see changes.
- :timeout (Numeric) - The number of seconds we’ll wait for a response when
  communicating with browser. Default is 5.
- :js_errors (Boolean) - When true, JavaScript errors get re-raised in Ruby.
- :pending_connection_errors (Boolean) - When main frame is still waiting for slow responses while timeout is
  reached PendingConnectionsError is raised. It’s better to figure out why you have slow responses and fix or
  block them rather than turn this setting off. Default is true.
- :browser_name (Symbol) - :chrome by default, only experimental support
  for :firefox for now.
- :browser_path (String) - Path to Chrome binary, you can also set ENV
  variable as BROWSER_PATH=some/path/chrome bundle exec rspec.
- :browser_options (Hash) - Additional command line options,
  see them all
  e.g. { "ignore-certificate-errors" => nil }
- :ignore_default_browser_options (Boolean) - Ferrum has a number of default
  options it passes to the browser, if you set this to true then only
  options you put in :browser_options will be passed to the browser,
  except required ones of course.
- :port (Integer) - Remote debugging port for headless Chrome.
- :host (String) - Remote debugging address for headless Chrome.
- :url (String) - URL for a running instance of Chrome. If this is set, a
  browser process will not be spawned.
- :ws_url (String) - Websocket url for a running instance of Chrome. If this is set, a
  browser process will not be spawned. It’s higher priority than :url, setting both doesn’t make sense.
- :process_timeout (Integer) - How long to wait for the Chrome process to
  respond on startup.
- :ws_max_receive_size (Integer) - How big messages to accept from Chrome
  over the web socket, in bytes. Defaults to 64MB. Incoming messages larger
  than this will cause a Ferrum::DeadBrowserError.
- :proxy (Hash) - Specify proxy settings, read more
- :save_path (String) - Path to save attachments with Content-Disposition header.
- :env (Hash) - Environment variables you’d like to pass through to the process

Navigation

go_to(url) : `String`

Navigate page to.

url String The url should include scheme unless you set base_url when
configuring driver.

page.go_to("https://github.com/")

back

Navigate to the previous page in history.

page.go_to("https://github.com/")
page.at_xpath("//a").click
page.back

forward

Navigate to the next page in history.

page.go_to("https://github.com/")
page.at_xpath("//a").click
page.back
page.forward

refresh

Reload current page.

page.go_to("https://github.com/")
page.refresh

stop

Stop all navigations and loading pending resources on the page

page.go_to("https://github.com/")
page.stop

position = **options

Set the position for the browser window

options Hash
- :left Integer
- :top Integer

browser.position = { left: 10, top: 20 }

position : `Array<Integer>`

Get the position for the browser window

browser.position # => [10, 20]

window_bounds = **options

Set window bounds

options Hash
- :left Integer
- :top Integer
- :width Integer
- :height Integer
- :window_state String

browser.window_bounds = { left: 10, top: 20, width: 1024, height: 768, window_state: "normal" }

window_bounds : `Hash<String, Integer | String>`

Get window bounds

browser.window_bounds # => { "left": 0, "top": 1286, "width": 10, "height": 10, "windowState": "normal" }

window_id : `Integer`

Current window id

browser.window_id # => 1

Finders

at_css(selector, **options) : `Node` | `nil`

Find node by selector. Runs document.querySelector within the document or
provided node.

selector String
options Hash
- :within Node | nil

page.go_to("https://github.com/")
page.at_css("a[aria-label='Issues you created']") # => Node

css(selector, **options) : `Array<Node>` | `[]`

Find nodes by selector. The method runs document.querySelectorAll within the
document or provided node.

selector String
options Hash
- :within Node | nil

page.go_to("https://github.com/")
page.css("a[aria-label='Issues you created']") # => [Node]

at_xpath(selector, **options) : `Node` | `nil`

Find node by xpath.

selector String
options Hash
- :within Node | nil

page.go_to("https://github.com/")
page.at_xpath("//a[@aria-label='Issues you created']") # => Node

xpath(selector, **options) : `Array<Node>` | `[]`

Find nodes by xpath.

selector String
options Hash
- :within Node | nil

page.go_to("https://github.com/")
page.xpath("//a[@aria-label='Issues you created']") # => [Node]

current_url : `String`

Returns current top window location href.

page.go_to("https://google.com/")
page.current_url # => "https://www.google.com/"

current_title : `String`

Returns current top window title

page.go_to("https://google.com/")
page.current_title # => "Google"

body : `String`

Returns current page’s html.

page.go_to("https://google.com/")
page.body # => '<html itemscope="" itemtype="http://schema.org/WebPage" lang="ru"><head>...

Screenshots

screenshot(**options) : `String` | `Integer`

Saves screenshot on a disk or returns it as base64.

options Hash
- :path String to save a screenshot on the disk. :encoding will be set to
  :binary automatically
- :encoding Symbol :base64 | :binary you can set it to return image as
  Base64
- :format String “jpeg” (“jpg”) | “png” | “webp”
- :quality Integer 0-100 works for jpeg only
- :full Boolean whether you need full page screenshot or a viewport
- :selector String css selector for given element, optional
- :area Hash area for screenshot, optional
  - :x Integer
  - :y Integer
  - :width Integer
  - :height Integer
- :scale Float zoom in/out
- :background_color Ferrum::RGBA.new(0, 0, 0, 0.0) to have specific background color

page.go_to("https://google.com/")
# Save on the disk in PNG
page.screenshot(path: "google.png") # => 134660
# Save on the disk in JPG
page.screenshot(path: "google.jpg") # => 30902
# Save to Base64 the whole page not only viewport and reduce quality
page.screenshot(full: true, quality: 60, encoding: :base64) # "iVBORw0KGgoAAAANSUhEUgAABAAAAAMACAYAAAC6uhUNAAAAAXNSR0IArs4c6Q...
# Save on the disk with the selected element in PNG
page.screenshot(path: "google.png", selector: 'textarea') # => 11340
# Save to Base64 with an area of the page in PNG
page.screenshot(path: "google.png", area: { x: 0, y: 0, width: 400, height: 300 }) # => 54239
# Save with specific background color
page.screenshot(background_color: Ferrum::RGBA.new(0, 0, 0, 0.0))

pdf(**options) : `String` | `Boolean`

Saves PDF on a disk or returns it as base64.

options Hash
- :path String to save a pdf on the disk. :encoding will be set to
  :binary automatically
- :encoding Symbol :base64 | :binary you can set it to return pdf as
  Base64
- :landscape Boolean paper orientation. Defaults to false.
- :scale Float zoom in/out
- :format symbol standard paper sizes :letter, :legal, :tabloid, :ledger, :A0, :A1, :A2, :A3, :A4, :A5, :A6
- :paper_width Float set paper width
- :paper_height Float set paper height
- See other native options you can pass

page.go_to("https://google.com/")
# Save to disk as a PDF
page.pdf(path: "google.pdf", paper_width: 1.0, paper_height: 1.0) # => true

mhtml(**options) : `String` | `Integer`

Saves MHTML on a disk or returns it as a string.

options Hash
- :path String to save a file on the disk.

page.go_to("https://google.com/")
page.mhtml(path: "google.mhtml") # => 87742

Network

page.network

traffic `Array<Network::Exchange>`

Returns all information about network traffic as Network::Exchange instance
which in general is a wrapper around request, response and error.

page.go_to("https://github.com/")
page.network.traffic # => [#<Ferrum::Network::Exchange, ...]

request : `Network::Request`

Page request of the main frame.

page.go_to("https://github.com/")
page.network.request # => #<Ferrum::Network::Request...

response : `Network::Response`

Page response of the main frame.

page.go_to("https://github.com/")
page.network.response # => #<Ferrum::Network::Response...

status : `Integer`

Contains the status code of the main page response (e.g., 200 for a
success). This is just a shortcut for response.status.

page.go_to("https://github.com/")
page.network.status # => 200

wait_for_idle(**options) : `Boolean`

Waits for network idle, returns true in case of success and false if there are still connections.

options Hash
- :connections Integer how many connections are allowed for network to be
  idling, 0 by default
- :duration Float sleep for given amount of time and check again, 0.05 by
  default
- :timeout Float during what time we try to check idle, browser.timeout
  by default

page.go_to("https://example.com/")
page.at_xpath("//a[text() = 'No UI changes button']").click
page.network.wait_for_idle # => true

wait_for_idle!(**options)

Waits for network idle or raises Ferrum::TimeoutError error. Accepts same arguments as wait_for_idle.

page.go_to("https://example.com/")
page.at_xpath("//a[text() = 'No UI changes button']").click
page.network.wait_for_idle! # might raise an error

clear(type)

Clear page’s cache or collected traffic.

type Symbol it is either :traffic or :cache

traffic = page.network.traffic # => []
page.go_to("https://github.com/")
traffic.size # => 51
page.network.clear(:traffic)
traffic.size # => 0

intercept(**options)

Set request interception for given options. This method is only sets request
interception, you should use on callback to catch requests and abort or
continue them.

options Hash
- :pattern String * by default
- :resource_type Symbol one of the resource types

browser = Ferrum::Browser.new
page = browser.create_page
page.network.intercept
page.on(:request) do |request|
  if request.match?(/bla-bla/)
    request.abort
  elsif request.match?(/lorem/)
    request.respond(body: "Lorem ipsum")
  else
    request.continue
  end
end
page.go_to("https://google.com")

authorize(**options, &block)

If site or proxy uses authorization you can provide credentials using this method.

options Hash
- :type Symbol :server | :proxy site or proxy authorization
- :user String
- :password String
&block accepts authenticated request, which you must subsequently allow or deny, if you don’t
care about unwanted requests just call request.continue.

page.network.authorize(user: "login", password: "pass") { |req| req.continue }
page.go_to("http://example.com/authenticated")
puts page.network.status # => 200
puts page.body # => Welcome, authenticated client

Since Chrome implements authorize using request interception you must continue or abort authorized requests. If you
already have code that uses interception you can use authorize without block, but if not you are obliged to pass
block, so this is version doesn’t pass block and can work just fine:

browser = Ferrum::Browser.new
page = browser.create_page
page.network.intercept
page.on(:request) do |request|
  if request.resource_type == "Image"
    request.abort
  else
    request.continue
  end
end

page.network.authorize(user: "login", password: "pass", type: :proxy)

page.go_to("https://google.com")

You used to call authorize method without block, but since it’s implemented using request interception there could be
a collision with another part of your code that also uses request interception, so that authorize allows the request
while your code denies but it’s too late. The block is mandatory now.

emulate_network_conditions(**options)

Activates emulation of network conditions.

options Hash
- :offline Boolean emulate internet disconnection, false by default
- :latency Integer minimum latency from request sent to response headers received (ms), 0 by
  default
- :download_throughput Integer maximal aggregated download throughput (bytes/sec), -1
  by default, disables download throttling
- :upload_throughput Integer maximal aggregated upload throughput (bytes/sec), -1
  by default, disables download throttling
- :connection_type String connection type if known, one of: none, cellular2g, cellular3g, cellular4g,
  bluetooth, ethernet, wifi, wimax, other. nil by default

page.network.emulate_network_conditions(connection_type: "cellular2g")
page.go_to("https://github.com/")

offline_mode

Activates offline mode for a page.

page.network.offline_mode
page.go_to("https://github.com/") # => Ferrum::StatusError (Request to https://github.com/ failed(net::ERR_INTERNET_DISCONNECTED))

cache(disable: `Boolean`)

Toggles ignoring cache for each request. If true, cache will not be used.

page.network.cache(disable: true)

Downloads

page.downloads

files `Array<Hash>`

Returns all information about downloaded files as a Hash.

page.go_to("http://localhost/attachment.pdf")
page.downloads.files # => [{"frameId"=>"E3316DF1B5383D38F8ADF7485005FDE3", "guid"=>"11a68745-98ac-4d54-9b57-9f9016c268b3", "url"=>"http://localhost/attachment.pdf", "suggestedFilename"=>"attachment.pdf", "totalBytes"=>4911, "receivedBytes"=>4911, "state"=>"completed"}]

wait(timeout)

Waits until the download is finished.

page.go_to("http://localhost/attachment.pdf")
page.downloads.wait

page.go_to("http://localhost/page")
page.downloads.wait { page.at_css("#download").click }

set_behavior(**options)

Sets behavior in case of file to be downloaded.

options Hash
- :save_path String absolute path of where to store the file
- :behavior Symbol deny | allow | allowAndName | default, allow by default

page.go_to("https://example.com/")
page.downloads.set_behavior(save_path: "/tmp", behavior: :allow)

Proxy

You can set a proxy with a :proxy option:

Ferrum::Browser.new(proxy: { host: "x.x.x.x", port: "8800", user: "user", password: "pa$$" })

:bypass can specify semi-colon-separated list of hosts for which proxy shouldn’t be used:

Ferrum::Browser.new(proxy: { host: "x.x.x.x", port: "8800", bypass: "*.google.com;*foo.com" })

In general passing a proxy option when instantiating a browser results in a browser running with proxy command line
flags, so that it affects all pages and contexts. You can create a page in a new context which can use its own proxy
settings:

browser = Ferrum::Browser.new

browser.create_page(proxy: { host: "x.x.x.x", port: 31337, user: "user", password: "password" }) do |page|
  page.go_to("https://api.ipify.org?format=json")
  page.body # => "x.x.x.x"
end

browser.create_page(proxy: { host: "y.y.y.y", port: 31337, user: "user", password: "password" }) do |page|
  page.go_to("https://api.ipify.org?format=json")
  page.body # => "y.y.y.y"
end

Mouse

page.mouse

scroll_to(x, y)

Scroll page to a given x, y

x Integer the pixel along the horizontal axis of the document that you
want displayed in the upper left
y Integer the pixel along the vertical axis of the document that you want
displayed in the upper left

page.go_to("https://www.google.com/search?q=Ruby+headless+driver+for+Capybara")
page.mouse.scroll_to(0, 400)

click(**options) : `Mouse`

Click given coordinates, fires mouse move, down and up events.

options Hash
- :x Integer
- :y Integer
- :delay Float defaults to 0. Delay between mouse down and mouse up events
- :button Symbol :left | :right, defaults to :left
- :count Integer defaults to 1
- :modifiers Integer bitfield for key modifiers. Seekeyboard.modifiers

down(**options) : `Mouse`

Mouse down for given coordinates.

options Hash
- :button Symbol :left | :right, defaults to :left
- :count Integer defaults to 1
- :modifiers Integer bitfield for key modifiers. Seekeyboard.modifiers

up(**options) : `Mouse`

Mouse up for given coordinates.

options Hash
- :button Symbol :left | :right, defaults to :left
- :count Integer defaults to 1
- :modifiers Integer bitfield for key modifiers. Seekeyboard.modifiers

move(x:, y:, steps: 1) : `Mouse`

Mouse move to given x and y.

options Hash
- :x Integer
- :y Integer
- :steps Integer defaults to 1. Sends intermediate mousemove events.

Keyboard

page.keyboard

down(key) : `Keyboard`

Dispatches a keydown event.

key String | Symbol Name of key such as “a”, :enter, :backspace

up(key) : `Keyboard`

Dispatches a keyup event.

key String | Symbol Name of key such as “b”, :enter, :backspace

type(*keys) : `Keyboard`

Sends a keydown, keypress/input, and keyup event for each character in the text.

text String | Array<String> | Array<Symbol> A text to type into a focused
element, [:Shift, "s"], "tring"

modifiers(keys) : `Integer`

Returns bitfield for a given keys

keys Array<Symbol> :alt | :ctrl | :command | :shift

Cookies

page.cookies

all : `Hash<String, Cookie>`

Returns cookies hash

page.cookies.all # => {"NID"=>#<Ferrum::Cookies::Cookie:0x0000558624b37a40 @attributes={"name"=>"NID", "value"=>"...", "domain"=>".google.com", "path"=>"/", "expires"=>1583211046.575681, "size"=>178, "httpOnly"=>true, "secure"=>false, "session"=>false}>}

: `Cookie`

Returns cookie

value String

page.cookies["NID"] # => <Ferrum::Cookies::Cookie:0x0000558624b67a88 @attributes={"name"=>"NID", "value"=>"...", "domain"=>".google.com", "path"=>"/", "expires"=>1583211046.575681, "size"=>178, "httpOnly"=>true, "secure"=>false, "session"=>false}>

set(value) : `Boolean`

Sets a cookie

value Hash
- :name String
- :value String
- :domain String
- :expires Integer
- :samesite String
- :httponly Boolean

page.cookies.set(name: "stealth", value: "omg", domain: "google.com") # => true

value Cookie

nid_cookie = page.cookies["NID"] # => <Ferrum::Cookies::Cookie:0x0000558624b67a88>
page.cookies.set(nid_cookie) # => true

remove(**options) : `Boolean`

Removes given cookie

options Hash
- :name String
- :domain String
- :url String

page.cookies.remove(name: "stealth", domain: "google.com") # => true

clear : `Boolean`

Removes all cookies for current page

page.cookies.clear # => true

store(path) : `Boolean`

Stores all cookies of current page in a file.

# Cookies are saved into cookies.yml
page.cookies.store # => 15657

load(path) : `Boolean`

Loads all cookies from the file and sets them for current page.

# Cookies are loaded from cookies.yml
page.cookies.load # => true

Headers

page.headers

get : `Hash`

Get all headers

set(headers) : `Boolean`

Set given headers. Eventually clear all headers and set given ones.

headers Hash key-value pairs for example "User-Agent" => "Browser"

add(headers) : `Boolean`

Adds given headers to already set ones.

headers Hash key-value pairs for example "Referer" => "http://example.com"

clear : `Boolean`

Clear all headers.

JavaScript

evaluate(expression, *args)

Evaluate and return result for given JS expression

expression String should be valid JavaScript
args Object you can pass arguments, though it should be a valid Node or a
simple value.

page.evaluate("[window.scrollX, window.scrollY]")

evaluate_async(expression, wait_time, *args)

Evaluate asynchronous expression and return result

expression String should be valid JavaScript
wait_time How long we should wait for Promise to resolve or reject
args Object you can pass arguments, though it should be a valid Node or a
simple value.

page.evaluate_async(%(arguments[0]({foo: "bar"})), 5) # => { "foo" => "bar" }

execute(expression, *args)

Execute expression. Doesn’t return the result

expression String should be valid JavaScript
args Object you can pass arguments, though it should be a valid Node or a
simple value.

page.execute(%(1 + 1)) # => true

evaluate_on_new_document(expression)

Evaluate JavaScript to modify things before a page load

expression String should be valid JavaScript

browser.evaluate_on_new_document <<~JS
  Object.defineProperty(navigator, "languages", {
    get: function() { return ["tlh"]; }
  });
JS

add_script_tag(**options) : `Boolean`

options Hash
- :url String
- :path String
- :content String
- :type String - text/javascript by default

page.add_script_tag(url: "http://example.com/stylesheet.css") # => true

add_style_tag(**options) : `Boolean`

options Hash
- :url String
- :path String
- :content String

page.add_style_tag(content: "h1 { font-size: 40px; }") # => true

bypass_csp(**options) : `Boolean`

options Hash
- :enabled Boolean, true by default

page.bypass_csp # => true
page.go_to("https://github.com/ruby-concurrency/concurrent-ruby/blob/master/docs-source/promises.in.md")
page.refresh
page.add_script_tag(content: "window.__injected = 42")
page.evaluate("window.__injected") # => 42

Emulation

disable_javascript

Disables Javascripts from the loaded HTML source.
You can still evaluate JavaScript with evaluate or execute.
Returns nothing.

page.disable_javascript

set_viewport

Overrides device screen dimensions and emulates viewport.

options Hash
- :width Integer, viewport width. 0 by default
- :height Integer, viewport height. 0 by default
- :scale_factor Float, device scale factor. 0 by default
- :mobile Boolean, whether to emulate mobile device. false by default

page.set_viewport(width: 1000, height: 600, scale_factor: 3)

Frames

frames : `Array[Frame] | []`

Returns all the frames current page have.

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
page.frames # =>
# [
#   #<Ferrum::Frame @id="C6D104CE454A025FBCF22B98DE612B12" @parent_id=nil @name=nil @state=:stopped_loading @execution_id=1>,
#   #<Ferrum::Frame @id="C09C4E4404314AAEAE85928EAC109A93" @parent_id="C6D104CE454A025FBCF22B98DE612B12" @state=:stopped_loading @execution_id=2>,
#   #<Ferrum::Frame @id="2E9C7F476ED09D87A42F2FEE3C6FBC3C" @parent_id="C6D104CE454A025FBCF22B98DE612B12" @state=:stopped_loading @execution_id=3>,
#   ...
# ]

main_frame : `Frame`

Returns page’s main frame, the top of the tree and the parent of all frames.

frame_by(**options) : `Frame | nil`

Find frame by given options.

options Hash
- :id String - Unique frame’s id that browser provides
- :name String - Frame’s name if there’s one

page.frame_by(id: "C6D104CE454A025FBCF22B98DE612B12")

Frame

id : `String`

Frame’s unique id.

parent_id : `String | nil`

Parent frame id if this one is nested in another one.

execution_id : `Integer`

Execution context id which is used by JS, each frame has it’s own context in
which JS evaluates.

name : `String | nil`

If frame was given a name it should be here.

state : `Symbol | nil`

One of the states frame’s in:

:started_loading
:navigated
:stopped_loading

url : `String`

Returns current frame’s location href.

page.go_to("https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe")
frame = page.frames[1]
frame.url # => https://interactive-examples.mdn.mozilla.net/pages/tabbed/iframe.html

title

Returns current frame’s title.

page.go_to("https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe")
frame = page.frames[1]
frame.title # => HTML Demo: <iframe>

main? : `Boolean`

If current frame is the main frame of the page (top of the tree).

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
frame = page.frame_by(id: "C09C4E4404314AAEAE85928EAC109A93")
frame.main? # => false

current_url : `String`

Returns current frame’s top window location href.

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
frame = page.frame_by(id: "C09C4E4404314AAEAE85928EAC109A93")
frame.current_url # => "https://www.w3schools.com/tags/tag_frame.asp"

current_title : `String`

Returns current frame’s top window title.

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
frame = page.frame_by(id: "C09C4E4404314AAEAE85928EAC109A93")
frame.current_title # => "HTML frame tag"

body : `String`

Returns current frame’s html.

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
frame = page.frame_by(id: "C09C4E4404314AAEAE85928EAC109A93")
frame.body # => "<html><head></head><body></body></html>"

doctype

Returns current frame’s doctype.

page.go_to("https://www.w3schools.com/tags/tag_frame.asp")
page.main_frame.doctype # => "<!DOCTYPE html>"

content = html

Sets a content of a given frame.

html String

page.go_to("https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe")
frame = page.frames[1]
frame.body # <html lang="en"><head><style>body {transition: opacity ease-in 0.2s; }...
frame.content = "<html><head></head><body><p>lol</p></body></html>"
frame.body # => <html><head></head><body><p>lol</p></body></html>

Dialogs

accept(text)

Accept dialog with given text or default prompt if applicable

text String

dismiss

Dismiss dialog

page.on(:dialog) do |dialog|
  if dialog.match?(/bla-bla/)
    dialog.accept
  else
    dialog.dismiss
  end
end
page.go_to("https://google.com")

Animation

You can slow down or speed up CSS animations.

playback_rate : `Integer`

Returns playback rate for CSS animations, defaults to 1.

playback_rate = value

Sets playback rate of CSS animations

value Integer

page.playback_rate = 2000
page.go_to("https://google.com")
page.playback_rate # => 2000

Node

node? : `Boolean`

frame_id

frame : `Frame`

Returns Frame object for current node, you can keep using
Finders for that object:

frame =  page.at_xpath("//iframe").frame # => Frame
frame.at_css("//a[text() = 'Log in']") # => Node

focus

focusable?

moving? : `Boolean`

wait_for_stop_moving

blur

type

click

hover

select_file

at_xpath

at_css

xpath

css

text

inner_text

value

property

attribute

evaluate

selected : `Array<Node>`

select

scroll_into_view

in_viewport?(of: `Node | nil`) : `Boolean`

remove

exists?

(chainable) Selects options by passed attribute.

page.at_xpath("//*[select]").select(["1"]) # => Node (select)
page.at_xpath("//*[select]").select(["text"], by: :text) # => Node (select)

Accept string, array or strings:

page.at_xpath("//*[select]").select("1")
page.at_xpath("//*[select]").select("1", "2")
page.at_xpath("//*[select]").select(["1", "2"])

Tracing

You can use tracing.record to create a trace file which can be opened in Chrome DevTools or
timeline viewer.

page.tracing.record(path: "trace.json") do
  page.go_to("https://www.google.com")
end

tracing.record(**options) : `String`

Accepts block, records trace and by default returns trace data from Tracing.tracingComplete event as output. When
path is specified returns true and stores trace data into file.

options Hash
- :path String save data on the disk, nil by default
- :encoding Symbol :base64 | :binary encode output as Base64 or plain text. :binary by default
- :timeout Float wait until file streaming finishes in the specified time or raise error, defaults to nil
- :screenshots Boolean capture screenshots in the trace, false by default
- :trace_config Hash<String, Object> config for
  trace, for categories
  see getCategories,
  only one trace config can be active at a time per browser.

Clean Up

reset

Closes browser tabs opened by the Browser instance.

# connect to a long-running Chrome process
browser = Ferrum::Browser.new(url: 'http://localhost:9222')

browser.go_to("https://github.com/")

# clean up, lest the tab stays there hanging forever
browser.reset

browser.quit

Thread safety

Ferrum is fully thread-safe. You can create one browser or a few as you wish and
start playing around using threads. Example below shows how to create a few pages
which share the same context. Context is similar to an incognito profile but you
can have more than one, think of it like it’s independent browser session:

browser = Ferrum::Browser.new
context = browser.contexts.create

t1 = Thread.new(context) do |c|
  page = c.create_page
  page.go_to("https://www.google.com/search?q=Ruby+headless+driver+for+Capybara")
  page.screenshot(path: "t1.png")
end

t2 = Thread.new(context) do |c|
  page = c.create_page
  page.go_to("https://www.google.com/search?q=Ruby+static+typing")
  page.screenshot(path: "t2.png")
end

t1.join
t2.join

context.dispose
browser.quit

or you can create two independent contexts:

browser = Ferrum::Browser.new

t1 = Thread.new(browser) do |b|
  context = b.contexts.create
  page = context.create_page
  page.go_to("https://www.google.com/search?q=Ruby+headless+driver+for+Capybara")
  page.screenshot(path: "t1.png")
  context.dispose
end

t2 = Thread.new(browser) do |b|
  context = b.contexts.create
  page = context.create_page
  page.go_to("https://www.google.com/search?q=Ruby+static+typing")
  page.screenshot(path: "t2.png")
  context.dispose
end

t1.join
t2.join

browser.quit

Development

After checking out the repo, run bundle install to install dependencies.

Then, run bundle exec rake test to run the tests. You can also run bin/console for an interactive prompt that will
allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the
version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version,
push git commits and the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub.

License

The gem is available as open source under the terms of the
MIT License.

ferrum

Ferrum - high-level API to control Chrome in Ruby

As simple as Puppeteer, though even simpler.

Index

Install

Examples

Docker

Customization

Navigation

go_to(url) : String

back

forward

refresh

stop

position = **options

position : Array<Integer>

window_bounds = **options

window_bounds : Hash<String, Integer | String>

window_id : Integer

Finders

at_css(selector, **options) : Node | nil

css(selector, **options) : Array<Node> | []

at_xpath(selector, **options) : Node | nil

xpath(selector, **options) : Array<Node> | []

current_url : String

current_title : String

body : String

Screenshots

screenshot(**options) : String | Integer

pdf(**options) : String | Boolean

mhtml(**options) : String | Integer

Network

traffic Array<Network::Exchange>

request : Network::Request

response : Network::Response

status : Integer

wait_for_idle(**options) : Boolean

wait_for_idle!(**options)

clear(type)

intercept(**options)

authorize(**options, &block)

emulate_network_conditions(**options)

offline_mode

cache(disable: Boolean)

Downloads

files Array<Hash>

wait(timeout)

set_behavior(**options)

Proxy

Mouse

scroll_to(x, y)

click(**options) : Mouse

down(**options) : Mouse

up(**options) : Mouse

move(x:, y:, steps: 1) : Mouse

Keyboard

down(key) : Keyboard

up(key) : Keyboard

type(*keys) : Keyboard

modifiers(keys) : Integer

Cookies

all : Hash<String, Cookie>

: Cookie

set(value) : Boolean

remove(**options) : Boolean

clear : Boolean

store(path) : Boolean

load(path) : Boolean

Headers

get : Hash

set(headers) : Boolean

add(headers) : Boolean

clear : Boolean

JavaScript

evaluate(expression, *args)

evaluate_async(expression, wait_time, *args)

execute(expression, *args)

evaluate_on_new_document(expression)

add_script_tag(**options) : Boolean

add_style_tag(**options) : Boolean

go_to(url) : `String`

position : `Array<Integer>`

window_bounds : `Hash<String, Integer | String>`

window_id : `Integer`

at_css(selector, **options) : `Node` | `nil`

css(selector, **options) : `Array<Node>` | `[]`

at_xpath(selector, **options) : `Node` | `nil`

xpath(selector, **options) : `Array<Node>` | `[]`

current_url : `String`

current_title : `String`

body : `String`

screenshot(**options) : `String` | `Integer`

pdf(**options) : `String` | `Boolean`

mhtml(**options) : `String` | `Integer`

traffic `Array<Network::Exchange>`

request : `Network::Request`

response : `Network::Response`

status : `Integer`

wait_for_idle(**options) : `Boolean`

cache(disable: `Boolean`)

files `Array<Hash>`

click(**options) : `Mouse`

down(**options) : `Mouse`

up(**options) : `Mouse`

move(x:, y:, steps: 1) : `Mouse`

down(key) : `Keyboard`

up(key) : `Keyboard`

type(*keys) : `Keyboard`

modifiers(keys) : `Integer`

all : `Hash<String, Cookie>`

: `Cookie`

set(value) : `Boolean`

remove(**options) : `Boolean`

clear : `Boolean`

store(path) : `Boolean`

load(path) : `Boolean`

get : `Hash`

set(headers) : `Boolean`

add(headers) : `Boolean`

clear : `Boolean`

add_script_tag(**options) : `Boolean`

add_style_tag(**options) : `Boolean`

bypass_csp(**options) : `Boolean`

frames : `Array[Frame] | []`

main_frame : `Frame`

frame_by(**options) : `Frame | nil`

id : `String`

parent_id : `String | nil`

execution_id : `Integer`

name : `String | nil`

state : `Symbol | nil`

url : `String`

main? : `Boolean`

current_url : `String`

current_title : `String`

body : `String`

playback_rate : `Integer`

node? : `Boolean`

frame : `Frame`

moving? : `Boolean`

selected : `Array<Node>`

in_viewport?(of: `Node | nil`) : `Boolean`

tracing.record(**options) : `String`