Module: Ferrum::Frame::Runtime

Included in:
Ferrum::Frame
Defined in:
lib/ferrum/frame/runtime.rb

Constant Summary collapse

INTERMITTENT_ATTEMPTS = 
ENV.fetch("FERRUM_INTERMITTENT_ATTEMPTS", 6).to_i
INTERMITTENT_SLEEP = 
ENV.fetch("FERRUM_INTERMITTENT_SLEEP", 0.1).to_f
EXECUTE_OPTIONS = 
{
  returnByValue: true,
  functionDeclaration: %(function() { %s })
}.freeze
DEFAULT_OPTIONS = 
{
  functionDeclaration: %(function() { return %s })
}.freeze
EVALUATE_ASYNC_OPTIONS = 
{
  awaitPromise: true,
  functionDeclaration: %(
    function() {
     return new Promise((__resolve, __reject) => {
       try {
         arguments[arguments.length] = r => __resolve(r);
         arguments.length = arguments.length + 1;
         setTimeout(() => __reject(new Error("timed out promise")), %s);
         %s
       } catch(error) {
         __reject(error);
       }
     });
    }
  )
}.freeze
SCRIPT_SRC_TAG = 
<<~JS
  const script = document.createElement("script");
  script.src = arguments[0];
  script.type = arguments[1];
  script.onload = arguments[2];
  document.head.appendChild(script);
JS
SCRIPT_TEXT_TAG = 
<<~JS
  const script = document.createElement("script");
  script.text = arguments[0];
  script.type = arguments[1];
  document.head.appendChild(script);
  arguments[2]();
JS
STYLE_TAG = 
<<~JS
  const style = document.createElement("style");
  style.type = "text/css";
  style.appendChild(document.createTextNode(arguments[0]));
  document.head.appendChild(style);
  arguments[1]();
JS
<<~JS
  const link = document.createElement("link");
  link.rel = "stylesheet";
  link.href = arguments[0];
  link.onload = arguments[1];
  document.head.appendChild(link);
JS

Instance Method Summary collapse

Instance Method Details

#add_script_tag(url: nil, path: nil, content: nil, type: "text/javascript") ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 95

def add_script_tag(url: nil, path: nil, content: nil, type: "text/javascript")
  expr, *args = if url
                  [SCRIPT_SRC_TAG, url, type]
                elsif path || content
                  if path
                    content = File.read(path)
                    content += "\n//# sourceURL=#{path}"
                  end
                  [SCRIPT_TEXT_TAG, content, type]
                end

  evaluate_async(expr, @page.timeout, *args)
end

#add_style_tag(url: nil, path: nil, content: nil) ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 109

def add_style_tag(url: nil, path: nil, content: nil)
  expr, *args = if url
                  [LINK_TAG, url]
                elsif path || content
                  if path
                    content = File.read(path)
                    content += "\n//# sourceURL=#{path}"
                  end
                  [STYLE_TAG, content]
                end

  evaluate_async(expr, @page.timeout, *args)
end

#evaluate(expression, *args) ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 63

def evaluate(expression, *args)
  call(*args, expression: expression)
end

#evaluate_async(expression, wait_time, *args) ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 67

def evaluate_async(expression, wait_time, *args)
  call(*args, expression: expression, wait_time: wait_time * 1000, **EVALUATE_ASYNC_OPTIONS)
end

#evaluate_on(node:, expression:, by_value: true, wait: 0) ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 76

def evaluate_on(node:, expression:, by_value: true, wait: 0)
  errors = [NodeNotFoundError, NoExecutionContextError]
  attempts, sleep = INTERMITTENT_ATTEMPTS, INTERMITTENT_SLEEP

  Ferrum.with_attempts(errors: errors, max: attempts, wait: sleep) do
    response = @page.command("DOM.resolveNode", nodeId: node.node_id)
    object_id = response.dig("object", "objectId")
    options = DEFAULT_OPTIONS.merge(objectId: object_id)
    options[:functionDeclaration] = options[:functionDeclaration] % expression
    options.merge!(returnByValue: by_value)

    response = @page.command("Runtime.callFunctionOn",
                       wait: wait, **options)["result"]
                      .tap { |r| handle_error(r) }

    by_value ? response.dig("value") : handle_response(response)
  end
end

#execute(expression, *args) ⇒ Object 



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# File 'lib/ferrum/frame/runtime.rb', line 71

def execute(expression, *args)
  call(*args, expression: expression, handle: false, **EXECUTE_OPTIONS)
  true
end