Class: Obxcura::Page

Inherits:
Object
  • Object
show all
Extended by:
Forwardable
Defined in:
lib/obxcura/page.rb

Overview

A single page/tab: a CDP target with its own attached session. Created via Browser#create_page — you rarely instantiate this directly.

Page owns the CDP session, navigation, in-page POSTs and lifecycle. Reading the DOM and executing JS belong to its main Frame (see Frame::DOM and Frame::Runtime), and Page delegates those (#evaluate, #html, #title, #at_css, ...).

Obscura has no paint engine, so there is deliberately no screenshot API.

Examples:

page = browser.create_page
page.goto("https://example.com")
page.html                 # rendered DOM after JS
page.title                # "Example Domain"
page.at_css("h1").text    # => "Example Domain"
page.close

Constant Summary collapse

TIMEOUT_HEADROOM =

Seconds of slack given to the CDP reply beyond a #post timeout, so the in-page abort is what surfaces rather than the transport giving up first.

Returns:

  • (Integer) 
5

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(browser, target_id:, session_id:) ⇒ Page

Returns a new instance of Page.

Parameters:

  • browser (Obxcura::Browser) —

    the owning browser.

  • target_id (String) —

    the CDP target id.

  • session_id (String) —

    the CDP session attached to the target.



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# File 'lib/obxcura/page.rb', line 45

def initialize(browser, target_id:, session_id:)
  @browser = browser
  @client = browser.client
  @target_id = target_id
  @session_id = session_id
  @frame = Frame.new(target_id, self)
  @load_queue = Queue.new
  @network_log = []
  @network_mutex = Mutex.new

  @client.subscribe(@session_id) { |method, params| dispatch_event(method, params) }
  command("Network.enable")
end

Instance Attribute Details

#client ⇒ String, ... (readonly)

Returns:

  • (String) —

    the CDP target id backing this page.

  • (String) —

    the CDP session id attached to the target.

  • (Obxcura::Client) —

    the shared CDP transport.

  • (Obxcura::Frame) —

    the page's main frame.



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# File 'lib/obxcura/page.rb', line 36

def client
  @client
end

#frame ⇒ String, ... (readonly)

Returns:

  • (String) —

    the CDP target id backing this page.

  • (String) —

    the CDP session id attached to the target.

  • (Obxcura::Client) —

    the shared CDP transport.

  • (Obxcura::Frame) —

    the page's main frame.



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# File 'lib/obxcura/page.rb', line 36

def frame
  @frame
end

#session_id ⇒ String, ... (readonly)

Returns:

  • (String) —

    the CDP target id backing this page.

  • (String) —

    the CDP session id attached to the target.

  • (Obxcura::Client) —

    the shared CDP transport.

  • (Obxcura::Frame) —

    the page's main frame.



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# File 'lib/obxcura/page.rb', line 36

def session_id
  @session_id
end

#target_id ⇒ String, ... (readonly)

Returns:

  • (String) —

    the CDP target id backing this page.

  • (String) —

    the CDP session id attached to the target.

  • (Obxcura::Client) —

    the shared CDP transport.

  • (Obxcura::Frame) —

    the page's main frame.



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# File 'lib/obxcura/page.rb', line 36

def target_id
  @target_id
end

Instance Method Details

#close ⇒ Obxcura::Page?

Close this page's target and stop listening for its events.

Returns:



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# File 'lib/obxcura/page.rb', line 89

def close
  @client.unsubscribe(@session_id)
  # @client.command("Network.clearBrowserCookies", { targetId: @target_id })
  @client.command("Target.closeTarget", { targetId: @target_id })
rescue ProtocolError
  # Target already gone — nothing to do.
ensure
  @browser.remove_page(self)
end

#close_connection ⇒ void

This method returns an undefined value.

Drop the underlying WebSocket connection (affects the whole browser).



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# File 'lib/obxcura/page.rb', line 102

def close_connection
  @client.close
end

#command(method, params = {}) ⇒ Hash

Send a CDP command scoped to this page's session.

Parameters:

  • method (String) —

    the CDP method name.

  • params (Hash) (defaults to: {}) —

    the method parameters.

Returns:

  • (Hash) —

    the command's result object.



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# File 'lib/obxcura/page.rb', line 125

def command(method, params = {})
  @client.command(method, params, session_id: @session_id)
end

#cookies ⇒ Array<Hash>

Returns the page's cookies as CDP cookie hashes.

Returns:

  • (Array<Hash>) —

    the page's cookies as CDP cookie hashes.



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# File 'lib/obxcura/page.rb', line 116

def cookies
  command("Storage.getCookies")["cookies"]
end

#goto(url) ⇒ self Also known as: go_to

Navigate to url and block until the page's load event fires. Aliased as go_to.

Parameters:

  • url (String) —

    the URL to navigate to.

Returns:

  • (self) 


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# File 'lib/obxcura/page.rb', line 78

def goto(url)
  @load_queue = Queue.new
  command("Page.navigate", url: url)
  wait_for_load
  self
end

#network_log ⇒ Array<Hash>

Requests this page issued, oldest first, as { url:, request_id:, finished: }.

Scope is deliberately narrow: Obscura emits Network events for requests the navigation drives (the document and its subresources), but not for ones started from script. A #post — or any in-page fetch/XMLHttpRequest — therefore never shows up here. Verified against Obscura 0.1.11: enabling the Network domain and issuing a scripted POST produces no events at all.

Returns:

  • (Array<Hash>) —

    a snapshot of the log, safe to iterate.



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# File 'lib/obxcura/page.rb', line 69

def network_log
  @network_mutex.synchronize { @network_log.map(&:dup) }
end

#post(url, payload, content_type, headers, timeout: nil) ⇒ Hash Also known as: xhr_post

POST from the page context via fetch. All values cross as arguments, never interpolated into the JS. Returns { status, ok, body } on any HTTP reply (including 4xx/5xx). A transport failure — the request never reached the server (blocked by CORS / private-network SSRF guard, mixed origin, or a dead host) — raises ConnectionError instead of silently returning nil.

timeout (seconds) is enforced in the page by racing the fetch against a timer, so a server that accepts the connection and never answers (some anti-bot endpoints tarpit non-stealth clients) fails in roughly timeout seconds instead of Client::DEFAULT_TIMEOUT. The CDP reply gets a little headroom past that so the in-page result is what we observe.

The race is deliberate, and not the obvious AbortSignal.timeout. Obscura does accept an abort signal, but when the abort actually fires, the fetch rejection is swallowed and the call returns undefined — the same in-page-throws-vanish behaviour that makes Frame::Runtime use { error: } sentinels. A rejection can't carry the reason across, so a resolved value has to. We still abort the underlying request once the timer wins, purely so it stops occupying the connection.

Requests made here do not appear in #network_log; see that method.

Parameters:

  • url (String) —

    the URL to POST to.

  • payload (String) —

    the raw request body.

  • content_type (String) —

    the Content-Type header value.

  • headers (Hash{String=>String}) —

    extra request headers.

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

    seconds to allow before giving up.

Returns:

  • (Hash) —

    { "status" => Integer, "ok" => Boolean, "body" => String }.

Raises:



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# File 'lib/obxcura/page.rb', line 159

def post(url, payload, content_type, headers, timeout: nil)
  timeout_ms = timeout && (timeout * 1000).to_i
  result = evaluate_func(<<~JS, url, payload, content_type, headers, timeout_ms, timeout: timeout && timeout + TIMEOUT_HEADROOM)
    function(url, payload, contentType, headers, timeoutMs) {
      const controller = timeoutMs ? new AbortController() : null;
      const init = {
        method: "POST",
        headers: Object.assign({ "Content-Type": contentType }, headers),
        body: payload
      };
      if (controller) init.signal = controller.signal;

      let timer = null;
      const request = fetch(url, init)
        .then((r) => r.text().then((body) => ({ status: r.status, ok: r.ok, body: body })))
        .catch((e) => ({ error: String(e) }))
        .then((outcome) => { if (timer) clearTimeout(timer); return outcome; });

      if (!timeoutMs) return request;

      return Promise.race([
        request,
        new Promise((resolve) => {
          timer = setTimeout(() => {
            if (controller) controller.abort();
            resolve({ timeout: true });
          }, timeoutMs);
        })
      ]);
    }
  JS

  raise TimeoutError, timeout_message(url) if result.is_a?(Hash) && result["timeout"]

  if result.nil? || result["error"]
    reason = result&.dig("error") || "no response (request blocked or never settled)"
    raise ConnectionError, "POST #{url} failed: #{reason}"
  end

  result
rescue TimeoutError
  raise TimeoutError, timeout_message(url)
end

#refresh ⇒ Hash Also known as: reload

Reload the page and block until it loads again. Aliased as reload.

Returns:

  • (Hash) —

    the CDP Page.reload result.



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# File 'lib/obxcura/page.rb', line 109

def refresh
  command("Page.reload")
  wait_for_load
end