feat(generators): Pass context and add ProviderState generator

lib/pact/provider/generators.rb

@@ -0,0 +1,26 @@
+
+require 'pact/provider/generators/provider_state';
+
+module Pact
+  module Provider  
+    class Generators
+      def self.add_generator generator
+        generators.unshift(generator)
+      end
+
+      def self.generators
+        @generators ||= []
+      end
+
+      def self.execute_generators object, interaction_context = nil
+        generators.each do | parser |
+          return parser.call(object, interaction_context) if parser.can_generate?(object)
+        end
+
+        raise Pact::UnrecognizePactFormatError.new("This document does not use a recognised Pact generator: #{object}")
+      end
+
+      add_generator(ProviderStateGenerator.new)
+    end
+  end
+end

lib/pact/provider/generators/provider_state.rb

@@ -0,0 +1,58 @@
+require 'pact/provider/generators'
+
+module Pact
+  module Provider
+    class ProviderStateGenerator
+
+
+      # rewrite of https://github.com/DiUS/pact-jvm/blob/master/core/support/src/main/kotlin/au/com/dius/pact/core/support/expressions/ExpressionParser.kt#L27
+      VALUES_SEPARATOR = ","
+      START_EXPRESSION = "\${"
+      END_EXPRESSION = '}'
+      def parse_expression expression, params 
+
+        return_string = []
+
+        buffer = expression;
+        # initial value
+        position = buffer.index(START_EXPRESSION)
+
+        while (position && position >= 0) 
+          if (position > 0) 
+            # add string 
+            return_string.push(buffer[0...position])
+          end
+          end_position = buffer.index(END_EXPRESSION, position)
+          if (end_position < 0)
+            raise "Missing closing brace in expression string \"#{$value}\""
+          end
+
+          variable = ""
+
+          if (end_position - position > 2)
+            expression = params[buffer[position+2...end_position]] || ""
+          end
+          return_string.push(expression)
+
+          buffer = buffer[end_position + 1...-1]
+          position = buffer.index(START_EXPRESSION)
+        end
+
+        return_string.join("")
+      end
+
+      def call hash, interaction_context = nil
+        params = interaction_context.state_params || {}
+
+        parse_expression hash["expression"], params
+      end
+
+      def can_generate?(hash)
+        hash.key?('type') && hash['type'] === 'ProviderState'
+      end
+    end
+  end
+end
+
+
+

lib/pact/provider/request.rb

@@ -1,6 +1,7 @@
 require 'json'
 require 'pact/reification'
 require 'pact/shared/null_expectation'
+require 'pact/provider/generators'
 
 module Pact
   module Provider
@@ -10,15 +11,21 @@ class Replayable
         # See https://github.com/rack/rack/blob/e7d741c6282ca4cf4e01506f5681e6e6b14c0b32/SPEC#L87-89
         NO_HTTP_PREFIX = ["CONTENT-TYPE", "CONTENT-LENGTH"]
 
-        def initialize expected_request
+        def initialize expected_request, interaction_context = nil
           @expected_request = expected_request
+          @interaction_context = interaction_context
         end
 
         def method
           expected_request.method
         end
 
         def path
+          if expected_request.methods.include? :generators
+            if expected_request.generators["path"]
+              return Pact::Provider::Generators.execute_generators(expected_request.generators["path"], @interaction_context)
+            end
+          end
           expected_request.full_path
         end
 

lib/pact/provider/rspec.rb

@@ -25,6 +25,7 @@ def honour_pactfile pact_source, pact_json, options
           pact_uri = pact_source.uri
           Pact.configuration.output_stream.puts "INFO: Reading pact at #{pact_uri}"
           consumer_contract = Pact::ConsumerContract.from_json(pact_json)
+
           suffix = pact_uri.metadata[:pending] ? " [PENDING]": ""
           example_group_description = "Verifying a pact between #{consumer_contract.consumer.name} and #{consumer_contract.provider.name}#{suffix}"
           example_group_metadata = { pactfile_uri: pact_uri, pact_criteria: options[:criteria] }
@@ -77,7 +78,6 @@ def describe_interaction_with_provider_state interaction, options
         end
 
         def describe_interaction interaction, options
-
           # pact_uri and pact_interaction are used by
           # Pact::Provider::RSpec::PactBrokerFormatter
 
@@ -103,8 +103,9 @@ def describe_interaction interaction, options
             before do | example |
               interaction_context.run_once :before do
                 Pact.configuration.logger.info "Running example '#{Pact::RSpec.full_description(example)}'"
-                set_up_provider_states interaction.provider_states, options[:consumer]
-                replay_interaction interaction, options[:request_customizer]
+                state_params = set_up_provider_states interaction.provider_states, options[:consumer]
+                interaction_context.state_params = state_params
+                replay_interaction interaction, options[:request_customizer], interaction_context
                 interaction_context.last_response = last_response
               end
             end
@@ -129,6 +130,7 @@ def describe_message expected_response, interaction_context
           include Pact::RSpec::Matchers
           extend Pact::Matchers::Messages
 
+
           let(:expected_contents) { expected_response.body[:contents].as_json }
           let(:response) { interaction_context.last_response }
           let(:differ) { Pact.configuration.body_differ_for_content_type diff_content_type }
@@ -214,6 +216,8 @@ class InteractionContext
 
         attr_accessor :last_response
 
+        attr_accessor :state_params
+
         def initialize
           @already_run = []
         end

lib/pact/provider/test_methods.rb

@@ -14,8 +14,8 @@ module TestMethods
       include Pact::Logging
       include Rack::Test::Methods
 
-      def replay_interaction interaction, request_customizer = nil
-        request = Request::Replayable.new(interaction.request)
+      def replay_interaction interaction, request_customizer = nil, interaction_context
+        request = Request::Replayable.new(interaction.request, interaction_context)
         request = request_customizer.call(request, interaction) if request_customizer
         args = [request.path, request.body, request.headers]
 
@@ -42,11 +42,17 @@ def parse_body_from_response rack_response
       end
 
       def set_up_provider_states provider_states, consumer, options = {}
+        state_params = {};
         # If there are no provider state, execute with an nil state to ensure global and base states are executed
         Pact.configuration.provider_state_set_up.call(nil, consumer, options) if provider_states.nil? || provider_states.empty?
         provider_states.each do | provider_state |
-          Pact.configuration.provider_state_set_up.call(provider_state.name, consumer, options.merge(params: provider_state.params))
+          result = Pact.configuration.provider_state_set_up.call(provider_state.name, consumer, options.merge(params: provider_state.params))
+          if result.is_a?(Hash)
+            state_params = state_params.merge(result)
+          end
         end
+
+        state_params
       end
 
       def tear_down_provider_states provider_states, consumer, options = {}