Extract network interceptor into a separate class

This would allow us to add more logic to it without polluting Driver
instance.

rb/lib/selenium/webdriver/common/driver_extensions/has_network_interception.rb

@@ -61,75 +61,10 @@ module HasNetworkInterception
         #
 
         def intercept(&block)
-          devtools.network.set_cache_disabled(cache_disabled: true)
-          devtools.fetch.on(:request_paused) do |params|
-            id = params['requestId']
-            if params.key?('responseStatusCode') || params.key?('responseErrorReason')
-              intercept_response(id, params, &pending_response_requests.delete(id))
-            else
-              intercept_request(id, params, &block)
-            end
-          end
-          devtools.fetch.enable(patterns: [{requestStage: 'Request'}, {requestStage: 'Response'}])
+          @interceptor ||= DevTools::NetworkInterceptor.new(devtools)
+          @interceptor.intercept(&block)
         end
 
-        private
-
-        def pending_response_requests
-          @pending_response_requests ||= {}
-        end
-
-        def intercept_request(id, params, &block)
-          original = DevTools::Request.from(id, params)
-          mutable = DevTools::Request.from(id, params)
-
-          block.call(mutable) do |&continue| # rubocop:disable Performance/RedundantBlockCall
-            pending_response_requests[id] = continue
-
-            if original == mutable
-              devtools.fetch.continue_request(request_id: id)
-            else
-              devtools.fetch.continue_request(
-                request_id: id,
-                url: mutable.url,
-                method: mutable.method,
-                post_data: mutable.post_data,
-                headers: mutable.headers.map do |k, v|
-                  {name: k, value: v}
-                end
-              )
-            end
-          end
-        end
-
-        def intercept_response(id, params)
-          return devtools.fetch.continue_request(request_id: id) unless block_given?
-
-          body = fetch_response_body(id)
-          original = DevTools::Response.from(id, body, params)
-          mutable = DevTools::Response.from(id, body, params)
-          yield mutable
-
-          if original == mutable
-            devtools.fetch.continue_request(request_id: id)
-          else
-            devtools.fetch.fulfill_request(
-              request_id: id,
-              body: (Base64.strict_encode64(mutable.body) if mutable.body),
-              response_code: mutable.code,
-              response_headers: mutable.headers.map do |k, v|
-                {name: k, value: v}
-              end
-            )
-          end
-        end
-
-        def fetch_response_body(id)
-          devtools.fetch.get_response_body(request_id: id).dig('result', 'body')
-        rescue Error::WebDriverError
-          # CDP fails to get body on certain responses (301) and raises:
-          # Can only get response body on requests captured after headers received.
-        end
       end # HasNetworkInterception
     end # DriverExtensions
   end # WebDriver

rb/lib/selenium/webdriver/devtools.rb

@@ -23,6 +23,7 @@ class DevTools
       autoload :ConsoleEvent, 'selenium/webdriver/devtools/console_event'
       autoload :ExceptionEvent, 'selenium/webdriver/devtools/exception_event'
       autoload :MutationEvent, 'selenium/webdriver/devtools/mutation_event'
+      autoload :NetworkInterceptor, 'selenium/webdriver/devtools/network_interceptor'
       autoload :PinnedScript, 'selenium/webdriver/devtools/pinned_script'
       autoload :Request, 'selenium/webdriver/devtools/request'
       autoload :Response, 'selenium/webdriver/devtools/response'

rb/lib/selenium/webdriver/devtools/network_interceptor.rb

@@ -0,0 +1,117 @@
+# frozen_string_literal: true
+
+# Licensed to the Software Freedom Conservancy (SFC) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The SFC licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+module Selenium
+  module WebDriver
+    class DevTools
+
+      #
+      # Wraps the network request/response interception, providing
+      # thread-safety guarantees and handling special cases such as browser
+      # canceling requests midst interception.
+      #
+      # You should not be using this class directly, use Driver#intercept instead.
+      # @api private
+      #
+
+      class NetworkInterceptor
+
+        def initialize(devtools)
+          @devtools = devtools
+        end
+
+        def intercept(&block)
+          devtools.network.set_cache_disabled(cache_disabled: true)
+
+          devtools.fetch.on(:request_paused) do |params|
+            id = params['requestId']
+            if params.key?('responseStatusCode') || params.key?('responseErrorReason')
+              intercept_response(id, params, &pending_response_requests.delete(id))
+            else
+              intercept_request(id, params, &block)
+            end
+          end
+
+          devtools.fetch.enable(patterns: [{requestStage: 'Request'}, {requestStage: 'Response'}])
+        end
+
+        private
+
+        attr_accessor :devtools
+
+        def pending_response_requests
+          @pending_response_requests ||= {}
+        end
+
+        def intercept_request(id, params, &block)
+          original = DevTools::Request.from(id, params)
+          mutable = DevTools::Request.from(id, params)
+
+          block.call(mutable) do |&continue| # rubocop:disable Performance/RedundantBlockCall
+            pending_response_requests[id] = continue
+
+            if original == mutable
+              devtools.fetch.continue_request(request_id: id)
+            else
+              devtools.fetch.continue_request(
+                request_id: id,
+                url: mutable.url,
+                method: mutable.method,
+                post_data: mutable.post_data,
+                headers: mutable.headers.map do |k, v|
+                  {name: k, value: v}
+                end
+              )
+            end
+          end
+        end
+
+        def intercept_response(id, params)
+          return devtools.fetch.continue_request(request_id: id) unless block_given?
+
+          body = fetch_response_body(id)
+          original = DevTools::Response.from(id, body, params)
+          mutable = DevTools::Response.from(id, body, params)
+          yield mutable
+
+          if original == mutable
+            devtools.fetch.continue_request(request_id: id)
+          else
+            devtools.fetch.fulfill_request(
+              request_id: id,
+              body: (Base64.strict_encode64(mutable.body) if mutable.body),
+              response_code: mutable.code,
+              response_headers: mutable.headers.map do |k, v|
+                {name: k, value: v}
+              end
+            )
+          end
+        end
+
+        def fetch_response_body(id)
+          devtools.fetch.get_response_body(request_id: id).dig('result', 'body')
+        rescue Error::WebDriverError
+          # CDP fails to get body on certain responses (301) and raises:
+          # Can only get response body on requests captured after headers received.
+        end
+
+      end # NetworkInterceptor
+    end # DevTools
+  end # WebDriver
+end # Selenium