Add VCR use_cassette support

Author: MUTOgen

README.md

@@ -382,16 +382,21 @@ yarn add cypress-on-rails --dev
 ### for VCR
 
 This only works when you start the Rails server with a single worker and single thread
+It can be used in two modes:
+- with separate insert/eject calls (more general, recommended way)
+- with use_cassette wrapper (supports only GraphQL integration)
 
-#### setup
+#### basic setup
 
-Add your VCR configuration to your `cypress_helper.rb`
+Add your VCR configuration to your `config/cypress_on_rails.rb`
 
 ```ruby
-require 'vcr'
-VCR.configure do |config|
-  config.hook_into :webmock
-end
+c.vcr_options = {
+  hook_into: :webmock,
+  default_cassette_options: { record: :once },
+  # It's possible to override cassette_library_dir using install_folder
+  cassette_library_dir: File.expand_path("#{__dir__}/../../spec/cypress/fixtures/vcr_cassettes")
+}
 ```
 
 Add to your `cypress/support/index.js`:
@@ -408,13 +413,16 @@ VCR.turn_off!
 WebMock.disable! if defined?(WebMock)
 ```
 
+#### insert/eject setup
+
 Add to your `config/cypress_on_rails.rb`:
 
 ```ruby
   c.use_vcr_middleware = !Rails.env.production? && ENV['CYPRESS'].present?
+  # c.use_vcr_use_cassette_middleware = !Rails.env.production? && ENV['CYPRESS'].present?
 ```
 
-#### usage
+#### insert/eject usage
 
 You have `vcr_insert_cassette` and `vcr_eject_cassette` available. https://www.rubydoc.info/github/vcr/vcr/VCR:insert_cassette
 
@@ -441,6 +449,63 @@ describe('My First Test', () => {
 })
 ```
 
+#### use_cassette setup
+
+Add to your `config/cypress_on_rails.rb`:
+
+```ruby
+  # c.use_vcr_middleware = !Rails.env.production? && ENV['CYPRESS'].present?
+  c.use_vcr_use_cassette_middleware = !Rails.env.production? && ENV['CYPRESS'].present?
+```
+
+Adjust record mode in `config/cypress_on_rails.rb` if needed:
+
+```ruby
+c.vcr_options = {
+  hook_into: :webmock,
+  default_cassette_options: { record: :once },
+} 
+```
+
+Add to your `cypress/support/command.js`:
+
+```js
+  // Add proxy-like mock to add operation name into query string
+  Cypress.Commands.add('mockGraphQL', () => {
+    cy.on('window:before:load', (win) => {
+      const originalFetch = win.fetch;
+      const fetch = (path, options, ...rest) => {
+        if (options && options.body) {
+          try {
+            const body = JSON.parse(options.body);
+            if (body.operationName) {
+              return originalFetch(`${path}?operation=${body.operationName}`, options, ...rest);
+            }
+          } catch (e) {
+            return originalFetch(path, options, ...rest);
+          }
+        }
+        return originalFetch(path, options, ...rest);
+      };
+      cy.stub(win, 'fetch', fetch);
+    });
+  });
+```
+
+Add to your `cypress/support/on-rails.js`, to `beforeEach`:
+
+```js
+  cy.mockGraphQL() // for GraphQL usage with use_cassette, see cypress/support/commands.rb
+```
+
+#### use_cassette usage
+
+There is nothing special to be called during the Cypress scenario. Each request is wrapped with `VCR.use_cassette`.
+Consider VCR configuration in `cypress_helper.rb` to ignore hosts.
+
+All cassettes will be recorded and saved automatically, using the pattern `<vcs_cassettes_path>/graphql/<operation_name>`
+
+
 ## `before_request` configuration
 
 You may perform any custom action before running a CypressOnRails command, such as authentication, or sending metrics.  Please set `before_request` as part of the CypressOnRails configuration.

lib/cypress_on_rails/configuration.rb

@@ -6,8 +6,10 @@ class Configuration
     attr_accessor :install_folder
     attr_accessor :use_middleware
     attr_accessor :use_vcr_middleware
+    attr_accessor :use_vcr_use_cassette_middleware
     attr_accessor :before_request
     attr_accessor :logger
+    attr_accessor :vcr_options
 
     # Attributes for backwards compatibility
     def cypress_folder
@@ -25,14 +27,17 @@ def initialize
 
     alias :use_middleware? :use_middleware
     alias :use_vcr_middleware? :use_vcr_middleware
+    alias :use_vcr_use_cassette_middleware? :use_vcr_use_cassette_middleware
 
     def reset
       self.api_prefix = ''
       self.install_folder = 'spec/e2e'
       self.use_middleware = true
       self.use_vcr_middleware = false
+      self.use_vcr_use_cassette_middleware = false
       self.before_request = -> (request) {}
       self.logger = Logger.new(STDOUT)
+      self.vcr_options = {}
     end
 
     def tagged_logged

lib/cypress_on_rails/railtie.rb

@@ -9,8 +9,12 @@ class Railtie < Rails::Railtie
         app.middleware.use Middleware
       end
       if CypressOnRails.configuration.use_vcr_middleware?
-        require 'cypress_on_rails/vcr_middleware'
-        app.middleware.use VCRMiddleware
+        require 'cypress_on_rails/vcr/insert_eject_middleware'
+        app.middleware.use Vcr::InsertEjectMiddleware
+      end
+      if CypressOnRails.configuration.use_vcr_use_cassette_middleware?
+        require 'cypress_on_rails/vcr/use_cassette_middleware'
+        app.middleware.use Vcr::UseCassetteMiddleware
       end
     end
   end

lib/cypress_on_rails/vcr/insert_eject_middleware.rb

@@ -0,0 +1,75 @@
+require_relative 'middleware_helpers'
+
+module CypressOnRails
+  module Vcr
+    # Middleware to handle vcr with insert/eject endpoints
+    class InsertEjectMiddleware
+      include MiddlewareHelpers
+
+      def initialize(app, vcr = nil)
+        @app = app
+        @vcr = vcr
+        @first_call = false
+      end
+
+      def call(env)
+        request = Rack::Request.new(env)
+        if request.path.start_with?('/__e2e__/vcr/insert')
+          configuration.tagged_logged { handle_insert(request) }
+        elsif request.path.start_with?('/__e2e__/vcr/eject')
+          configuration.tagged_logged { handle_eject }
+        else
+          do_first_call unless @first_call
+          @app.call(env)
+        end
+      end
+
+      private
+
+      def handle_insert(req)
+        WebMock.enable! if defined?(WebMock)
+        vcr.turn_on!
+        body = parse_request_body(req)
+        logger.info "vcr insert cassette: #{body}"
+        cassette_name, options = extract_cassette_info(body)
+        vcr.insert_cassette(cassette_name, options)
+        [201, { 'Content-Type' => 'application/json' }, [{ 'message': 'OK' }.to_json]]
+      rescue JSON::ParserError => e
+        [400, { 'Content-Type' => 'application/json' }, [{ 'message': e.message }.to_json]]
+      rescue LoadError, ArgumentError => e
+        [500, { 'Content-Type' => 'application/json' }, [{ 'message': e.message }.to_json]]
+      end
+
+      def parse_request_body(req)
+        JSON.parse(req.body.read)
+      end
+
+      def extract_cassette_info(body)
+        cassette_name = body[0]
+        options = (body[1] || {}).symbolize_keys
+        options[:record] = options[:record].to_sym if options[:record]
+        options[:match_requests_on] = options[:match_requests_on].map(&:to_sym) if options[:match_requests_on]
+        options[:serialize_with] = options[:serialize_with].to_sym if options[:serialize_with]
+        options[:persist_with] = options[:persist_with].to_sym if options[:persist_with]
+        [cassette_name, options]
+      end
+
+      def handle_eject
+        logger.info 'vcr eject cassette'
+        vcr.eject_cassette
+        do_first_call
+        [201, { 'Content-Type' => 'application/json' }, [{ 'message': 'OK' }.to_json]]
+      rescue LoadError, ArgumentError => e
+        [500, { 'Content-Type' => 'application/json' }, [{ 'message': e.message }.to_json]]
+      end
+
+      def do_first_call
+        @first_call = true
+        vcr.turn_off!
+        WebMock.disable! if defined?(WebMock)
+      rescue LoadError
+        # nop
+      end
+    end
+  end
+end

lib/cypress_on_rails/vcr/middleware_helpers.rb

@@ -0,0 +1,51 @@
+require 'cypress_on_rails/middleware_config'
+
+module CypressOnRails
+  module Vcr
+    # Provides helper methods for VCR middlewares
+    module MiddlewareHelpers
+      include MiddlewareConfig
+
+      def vcr
+        @vcr ||= configure_vcr
+      end
+
+      def cassette_library_dir
+        configuration.vcr_options&.fetch(:cassette_library_dir) do
+          "#{configuration.install_folder}/fixtures/vcr_cassettes"
+        end
+      end
+
+      private
+
+      def configure_vcr
+        require 'vcr'
+        VCR.configure do |config|
+          config.cassette_library_dir = cassette_library_dir
+          apply_vcr_options(config) if configuration.vcr_options.present?
+        end
+        VCR
+      end
+
+      def apply_vcr_options(config)
+        configuration.vcr_options.each do |option, value|
+          next if option.to_sym == :cassette_library_dir
+
+          apply_vcr_option(config, option, value)
+        end
+      end
+
+      def apply_vcr_option(config, option, value)
+        return unless config.respond_to?(option) || config.respond_to?("#{option}=")
+
+        if config.respond_to?("#{option}=")
+          config.send("#{option}=", value)
+        elsif value.is_a?(Array)
+          config.send(option, *value)
+        else
+          config.send(option, value)
+        end
+      end
+    end
+  end
+end

lib/cypress_on_rails/vcr/use_cassette_middleware.rb

@@ -0,0 +1,56 @@
+require_relative 'middleware_helpers'
+
+module CypressOnRails
+  module Vcr
+    # Middleware to handle vcr with use_cassette
+    class UseCassetteMiddleware
+      include MiddlewareHelpers
+
+      def initialize(app, vcr = nil)
+        @app = app
+        @vcr = vcr
+      end
+
+      def call(env)
+        return @app.call(env) if should_not_use_vcr?
+
+        initialize_vcr
+        handle_request_with_vcr(env)
+      end
+
+      private
+
+      def vcr_defined?
+        defined?(VCR) != nil
+      end
+
+      def should_not_use_vcr?
+        vcr_defined? &&
+          VCR.configuration.cassette_library_dir.present? &&
+          VCR.configuration.cassette_library_dir != cassette_library_dir
+      end
+
+      def initialize_vcr
+        WebMock.enable! if defined?(WebMock)
+        vcr.turn_on!
+      end
+
+      def handle_request_with_vcr(env)
+        request = Rack::Request.new(env)
+        cassette_name = fetch_request_cassette(request)
+        vcr.use_cassette(cassette_name) do
+          logger.info "Handle request with cassette name: #{cassette_name}"
+          @app.call(env)
+        end
+      end
+
+      def fetch_request_cassette(request)
+        if request.path.start_with?('/graphql') && request.params.key?('operation')
+          "#{request.path}/#{request.params['operation']}"
+        else
+          request.path
+        end
+      end
+    end
+  end
+end