SeleniumHQ/selenium · error · TypeError

expected #{Proxy.name}, got #{proxy.inspect}:#{proxy.class}

Error message

expected #{Proxy.name}, got #{proxy.inspect}:#{proxy.class}

What it means

Raised by Firefox::Profile#proxy= (TypeError) when the argument is not an instance of Selenium::WebDriver::Proxy. The setter then switches on proxy.type to configure the corresponding network.proxy.* preferences.

Source

Thrown at rb/lib/selenium/webdriver/firefox/profile.rb:138

        def load_no_focus_lib=(value)
          WebDriver.logger.deprecate('Firefox::Profile#load_no_focus_lib=', id: :firefox_profile)
          @load_no_focus_lib = value
        end

        def log_file=(file)
          @log_file = file
          self[WEBDRIVER_PREFS[:log_file]] = file
        end

        def add_extension(path, name = extension_name_for(path))
          WebDriver.logger.deprecate('Firefox::Profile#add_extension', 'Driver#install_addon',
                                     id: :firefox_profile)
          @extensions[name] = Extension.new(path)
        end

        def proxy=(proxy)
          raise TypeError, "expected #{Proxy.name}, got #{proxy.inspect}:#{proxy.class}" unless proxy.is_a? Proxy

          case proxy.type
          when :manual
            self['network.proxy.type'] = 1

            set_manual_proxy_preference 'http', proxy.http
            set_manual_proxy_preference 'ssl', proxy.ssl
            set_manual_proxy_preference 'socks', proxy.socks

            self['network.proxy.no_proxies_on'] = proxy.no_proxy || ''
          when :pac
            self['network.proxy.type'] = 2
            self['network.proxy.autoconfig_url'] = proxy.pac
          when :auto_detect
            self['network.proxy.type'] = 4
          else
            raise ArgumentError, "unsupported proxy type #{proxy.type}"
          end

View on GitHub (pinned to aa36b38e69)

Solutions

1. Construct a Selenium::WebDriver::Proxy.new(type: :manual, http: 'host:8080') and assign that.
2. Prefer setting the proxy on Capabilities (options.proxy = Proxy.new(...)) rather than on the Firefox profile directly.
3. If you only have a hash, convert it with Proxy.new(hash).

Example fix

// before
profile.proxy = {type: :manual, http: 'proxy.example.com:8080'}

// after
profile.proxy = Selenium::WebDriver::Proxy.new(
  type: :manual, http: 'proxy.example.com:8080'
)
# or preferred: set on capabilities
options = Selenium::WebDriver::Firefox::Options.new
options.proxy = Selenium::WebDriver::Proxy.new(type: :manual, http: 'proxy.example.com:8080')

proxy = Selenium::WebDriver::Proxy.new(proxy_hash) unless proxy.is_a?(Selenium::WebDriver::Proxy)
profile.proxy = proxy

def selenium_proxy?(obj)
  obj.is_a?(Selenium::WebDriver::Proxy)
end

When it happens

Trigger: Assigning a hash of proxy settings (e.g. {type: :manual, http: 'host:8080'}) or a URI/string instead of a Proxy object to profile.proxy=.

Common situations: Building proxy config from a hash read out of Capabilities by mistake; passing the proxy at the wrong layer (profile vs Capabilities); confusing this with the Capabilities proxy= which accepts a hash.

Related errors

• expected one of #{VALID_PREFERENCE_TYPES.inspect}, got #{val
• unsupported proxy type #{proxy.type}
• Port needs to be an integer
• Port number must be in the range 1..65535
• Please pass in a Boolean to this call

AI-assisted analysis of SeleniumHQ/selenium@aa36b38e69 (2026-08-14). Data as JSON: /api/errors/35742e4dd5339017. Report an issue: GitHub.