Making CORS work

lib/pact/consumer/mock_service/app.rb

@@ -8,11 +8,14 @@
 require 'pact/consumer/mock_service/interaction_list'
 require 'pact/consumer/mock_service/interaction_delete'
 require 'pact/consumer/mock_service/interaction_post'
+require 'pact/consumer/mock_service/interaction_options'
 require 'pact/consumer/mock_service/interaction_replay'
 require 'pact/consumer/mock_service/missing_interactions_get'
 require 'pact/consumer/mock_service/verification_get'
 require 'pact/consumer/mock_service/log_get'
 require 'pact/consumer/mock_service/pact_post'
+require 'pact/consumer/mock_service/pact_options'
+require 'pact/consumer/mock_service/candidate_options'
 require 'pact/support'
 
 AwesomePrint.defaults = {
@@ -33,14 +36,18 @@ def initialize options = {}
         @name = options.fetch(:name, "MockService")
         pact_dir = options[:pact_dir]
         interactions = []
+        cors_enabled= options[:cors_enabled]
         @handlers = [
           MissingInteractionsGet.new(@name, @logger, interaction_list),
           VerificationGet.new(@name, @logger, interaction_list, log_description),
           InteractionPost.new(@name, @logger, interaction_list),
           InteractionDelete.new(@name, @logger, interaction_list),
+          InteractionOptions.new(@name, @logger),
           LogGet.new(@name, @logger),
           PactPost.new(@name, @logger, interactions, pact_dir),
-          InteractionReplay.new(@name, @logger, interaction_list, interactions)
+          PactOptions.new(@name, @logger),
+          CandidateOptions.new(@name, @logger, cors_enabled),
+          InteractionReplay.new(@name, @logger, interaction_list, interactions, cors_enabled),
         ]
       end
 
@@ -65,14 +72,17 @@ def call env
         response = []
         begin
           relevant_handler = @handlers.detect { |handler| handler.match? env }
-          response = add_cors_header(relevant_handler.respond(env))
+          res= relevant_handler.respond(env)
+          response= relevant_handler.enable_cors? ? add_cors_header(res) : res
         rescue StandardError => e
           @logger.error 'Error ocurred in mock service:'
           @logger.ap e, :error
+          puts e.inspect
+          puts e.backtrace
           @logger.ap e.backtrace
           response = [500, {'Content-Type' => 'application/json'}, [{message: e.message, backtrace: e.backtrace}.to_json]]
         rescue Exception => e
-          @logger.error 'Exception ocurred in mock service:'
+          @logger.error 'Exception occurred in mock service:'
           @logger.ap e, :error
           @logger.ap e.backtrace
           raise e

lib/pact/consumer/mock_service/candidate_options.rb

@@ -0,0 +1,22 @@
+require 'pact/consumer/mock_service/web_request_options'
+
+module Pact
+  module Consumer
+
+    # Allow web preflight requests to the intaractions setup by the user
+    # This is only needed in a CORS setup, where the browsers do
+    # an OPTIONS call before a DELETE, POST (for most request), etc. in a cross domain requests
+    class CandidateOptions < WebRequestOptions
+      def initialize name, logger, cors_enabled
+        super(name,logger)
+        @cors_enabled = cors_enabled
+      end
+
+      # Will match all requests to OPTIONS when in CORS mode
+      def request_path_match? env
+        @cors_enabled
+      end
+    end
+  end
+end
+

lib/pact/consumer/mock_service/interaction_delete.rb

@@ -1,10 +1,10 @@
 require 'pact/consumer/mock_service/rack_request_helper'
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
 
-    class InteractionDelete < MockServiceAdministrationEndpoint
+    class InteractionDelete < WebRequestAdministration
 
       include RackRequestHelper
 

lib/pact/consumer/mock_service/interaction_options.rb

@@ -0,0 +1,14 @@
+require 'pact/consumer/mock_service/web_request_options'
+
+module Pact
+  module Consumer
+
+    # Allow web preflight requests to Pact infrastructure
+    # Browsers typically do a OPTIONS before a POST for cross domain requests
+    class InteractionOptions < WebRequestOptions
+      def request_path
+        '/interactions'
+      end
+    end
+  end
+end

lib/pact/consumer/mock_service/interaction_post.rb

@@ -1,8 +1,8 @@
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
-    class InteractionPost < MockServiceAdministrationEndpoint
+    class InteractionPost < WebRequestAdministration
 
       attr_accessor :interaction_list
 

lib/pact/consumer/mock_service/interaction_replay.rb

@@ -24,11 +24,12 @@ class InteractionReplay
 
       attr_accessor :name, :logger, :interaction_list, :interactions
 
-      def initialize name, logger, interaction_list, interactions
+      def initialize name, logger, interaction_list, interactions, cors_enabled=false
         @name = name
         @logger = logger
         @interaction_list = interaction_list
         @interactions = DistinctInteractionsFilter.new(interactions)
+        @cors_enabled = cors_enabled
       end
 
       def match? env
@@ -39,6 +40,10 @@ def respond env
         find_response request_as_hash_from(env)
       end
 
+      def enable_cors?
+        @cors_enabled
+      end
+
       private
 
       def find_response request_hash

lib/pact/consumer/mock_service/log_get.rb

@@ -1,8 +1,8 @@
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
-    class LogGet < MockServiceAdministrationEndpoint
+    class LogGet < WebRequestAdministration
 
       include RackRequestHelper
 

lib/pact/consumer/mock_service/missing_interactions_get.rb

@@ -1,9 +1,9 @@
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
 
-    class MissingInteractionsGet < MockServiceAdministrationEndpoint
+    class MissingInteractionsGet < WebRequestAdministration
       include RackRequestHelper
 
       def initialize name, logger, interaction_list

lib/pact/consumer/mock_service/mock_service_administration_endpoint.rb

@@ -13,9 +13,7 @@ def initialize name, logger
       include RackRequestHelper
 
       def match? env
-        headers_from(env)['X-Pact-Mock-Service'] &&
-        env['PATH_INFO'] == request_path &&
-          env['REQUEST_METHOD'] == request_method
+        (request_header_match? env) && (request_path_match? env) && (request_method_match? env)
       end
 
       def request_path
@@ -26,6 +24,18 @@ def request_method
         raise NotImplementedError
       end
 
+      private
+      def request_header_match? env
+        raise NotImplementedError
+      end
+      def request_path_match? env
+        env['PATH_INFO'] == request_path
+      end
+      def request_method_match? env
+        env['REQUEST_METHOD'] == request_method
+      end
+
+
     end
   end
 end

lib/pact/consumer/mock_service/pact_options.rb

@@ -0,0 +1,14 @@
+require 'pact/consumer/mock_service/web_request_options'
+
+module Pact
+  module Consumer
+
+    # Allow web preflight requests to Pact infrastructure
+    # Browsers typically do a OPTIONS before a POST for cross domain requests
+    class PactOptions < WebRequestOptions
+      def request_path
+        '/pact'
+      end
+    end
+  end
+end

lib/pact/consumer/mock_service/pact_post.rb

@@ -1,9 +1,9 @@
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
 require 'pact/consumer_contract/consumer_contract_writer'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
-    class PactPost < MockServiceAdministrationEndpoint
+    class PactPost < WebRequestAdministration
 
       attr_accessor :consumer_contract, :interactions, :default_options
 

lib/pact/consumer/mock_service/rack_request_helper.rb

@@ -1,3 +1,4 @@
+require 'cgi/core'
 module Pact
   module Consumer
 

lib/pact/consumer/mock_service/verification_get.rb

@@ -1,8 +1,8 @@
-require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+require 'pact/consumer/mock_service/web_request_administration'
 
 module Pact
   module Consumer
-    class VerificationGet < MockServiceAdministrationEndpoint
+    class VerificationGet < WebRequestAdministration
 
       include RackRequestHelper
       attr_accessor :interaction_list, :log_description

lib/pact/consumer/mock_service/web_request_administration.rb

@@ -0,0 +1,30 @@
+require 'pact/consumer/mock_service/rack_request_helper'
+require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+
+module Pact
+  module Consumer
+
+    # Administration web requests (GET, DELETE, POST, PUT, etc.)
+    class WebRequestAdministration < MockServiceAdministrationEndpoint
+
+      def request_path
+        raise NotImplementedError
+      end
+
+      def request_method
+        raise NotImplementedError
+      end
+
+      def enable_cors?
+        true
+      end
+
+      private
+      def request_header_match? env
+        headers_from(env)['X-Pact-Mock-Service']
+      end
+
+    end
+
+  end
+end

lib/pact/consumer/mock_service/web_request_options.rb

@@ -0,0 +1,51 @@
+require 'pact/consumer/mock_service/rack_request_helper'
+require 'pact/consumer/mock_service/mock_service_administration_endpoint'
+
+module Pact
+  module Consumer
+
+    # Web Request is OPTIONS, which is a preflight brower request made
+    # before sending the actual POST, DELETE, etc. in CORS cases
+    class WebRequestOptions < MockServiceAdministrationEndpoint
+
+      include RackRequestHelper
+
+      def request_path
+        raise NotImplementedError
+      end
+
+      def request_method
+        'OPTIONS'
+      end
+
+      def respond env
+        logger.info "Preflight browser CORS check before sending data okayed (OPTIONS request)"
+        [200,
+         {
+             'Access-Control-Allow-Origin' => '*',
+             # '*' is not allowed for 'Access-Control-Allow-Headers. We need to echo back what was provided!
+             'Access-Control-Allow-Headers' => headers_from(env)["Access-Control-Request-Headers"],
+             'Access-Control-Allow-Methods' => 'DELETE, POST, GET, HEAD, PUT, TRACE, CONNECT'},
+         ["Browser, go ahead and send the actual request"]
+        ]
+      end
+
+      # Access-Control-Domain does not work on OPTIONs requests.
+      def enable_cors?
+        false
+      end
+
+      private
+      # 'X-Pact-Mock-Service' header is set as a normal header in regular requests (PUT, GET, POST, etc.)
+      # However, browsers set it within Access-Control-Request-Headers in case of OPTIONS request
+      # (web browsers make an OPTIONS request prior to the normal request in case of CORS request)
+      # For OPTIONS request, headers are different
+      def request_header_match? env
+        headers_from(env)["Access-Control-Request-Headers"].nil? ? false
+        : headers_from(env)["Access-Control-Request-Headers"].match(/x-pact-mock-service/)
+      end
+
+    end
+
+  end
+end

lib/pact/mock_service/cli.rb

@@ -13,6 +13,7 @@ class CLI < Thor
       method_option :port, aliases: "-p", desc: "Port on which to run the service"
       method_option :log, aliases: "-l", desc: "File to which to log output"
       method_option :quiet, aliases: "-q", desc: "If true, no admin messages will be shown"
+      method_option :cors_enabled, aliases: "-o", desc: "If true, mocks requests will have access control origin headers set to '*'"
 
       def service
         RunStandaloneMockService.call(options)
@@ -37,6 +38,7 @@ def self.call options
           log.sync = true
           service_options[:log_file] = log
         end
+        service_options[:cors] = true if options[:cors]
 
         port = options[:port] || FindAPort.available_port
         mock_service = Pact::Consumer::MockService.new(service_options)