feat(generators): Add ProviderState generator & others

lib/pact/provider/generator/boolean.rb

@@ -0,0 +1,16 @@
+module Pact
+  module Provider
+    module Generator
+      # Boolean provides the boolean generator which will give a true or false value
+      class Boolean
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'Boolean'
+        end
+
+        def call(_hash, _params = nil, _example_value = nil)
+          [true, false].sample
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/date.rb

@@ -0,0 +1,64 @@
+require 'date'
+
+module Pact
+  module Provider
+    module Generator
+      # Date provides the time generator which will give the current date in the defined format
+      class Date
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == type
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          format = hash['format'] || default_format
+          ::Time.now.strftime(convert_from_java_simple_date_format(format))
+        end
+
+        def type
+          'Date'
+        end
+
+        def default_format
+          'yyyy-MM-dd'
+        end
+
+        # Format for the pact specficiation should be the Java DateTimeFormmater
+        # This tries to convert to something Ruby can format.
+        def convert_from_java_simple_date_format(format)
+          # Year
+          format.sub!(/(?<!%)y{4,}/, '%Y')
+          format.sub!(/(?<!%)y{1,}/, '%y')
+
+          # Month
+          format.sub!(/(?<!%)M{4,}/, '%B')
+          format.sub!(/(?<!%)M{3}/, '%b')
+          format.sub!(/(?<!%)M{1,2}/, '%m')
+
+          # Week
+          format.sub!(/(?<!%)M{1,}/, '%W')
+
+          # Day
+          format.sub!(/(?<!%)D{1,}/, '%j')
+          format.sub!(/(?<!%)d{1,}/, '%d')
+          format.sub!(/(?<!%)E{4,}/, '%A')
+          format.sub!(/(?<!%)D{1,}/, '%a')
+          format.sub!(/(?<!%)u{1,}/, '%u')
+
+          # Time
+          format.sub!(/(?<!%)a{1,}/, '%p')
+          format.sub!(/(?<!%)k{1,}/, '%H')
+          format.sub!(/(?<!%)n{1,}/, '%M')
+          format.sub!(/(?<!%)s{1,}/, '%S')
+          format.sub!(/(?<!%)S{1,}/, '%L')
+
+          # Timezone
+          format.sub!(/(?<!%)z{1,}/, '%z')
+          format.sub!(/(?<!%)Z{1,}/, '%z')
+          format.sub!(/(?<!%)X{1,}/, '%Z')
+
+          format
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/datetime.rb

@@ -0,0 +1,18 @@
+require 'date'
+
+module Pact
+  module Provider
+    module Generator
+      # DateTime provides the time generator which will give the current date time in the defined format
+      class DateTime < Date
+        def type
+          'DateTime'
+        end
+
+        def default_format
+          'yyyy-MM-dd HH:mm'
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/provider_state.rb

@@ -0,0 +1,57 @@
+require 'pact/logging'
+
+module Pact
+  module Provider
+    module Generator
+      # ProviderState provides the provider state generator which will inject
+      # values provided by the provider state setup url.
+      class ProviderState
+        include Pact::Logging
+
+        # 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 can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'ProviderState'
+        end
+
+        def call(hash, params = nil, _example_value = nil)
+          params ||= {}
+          parse_expression hash['expression'], params
+        end
+
+        def parse_expression(expression, params)
+          return_string = []
+          buffer = expression
+          # initial value
+          position = buffer.index(START_EXPRESSION)
+
+          while position && position >= 0
+            if position.positive?
+              # add string
+              return_string.push(buffer[0...position])
+            end
+            end_position = buffer.index(END_EXPRESSION, position)
+            raise 'Missing closing brace in expression string' if !end_position || end_position.negative?
+
+            variable = buffer[position + 2...end_position]
+
+            if !params[variable]
+              logger.info "Could not subsitute provider state key #{variable}, have #{params}"
+            end
+
+            expression = params[variable] || ''
+            return_string.push(expression)
+
+            buffer = buffer[end_position + 1...-1]
+            position = buffer.index(START_EXPRESSION)
+          end
+
+          return_string.join('')
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/random_decimal.rb

@@ -0,0 +1,39 @@
+require 'bigdecimal'
+
+module Pact
+  module Provider
+    module Generator
+      # RandomDecimal provides the random decimal generator which will generate a decimal value of digits length
+      class RandomDecimal
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'RandomDecimal'
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          digits = hash['digits'] || 6
+
+          raise 'RandomDecimalGenerator digits must be > 0, got $digits' if digits < 1
+
+          return rand(0..9) if digits == 1
+
+          return rand(0..9) + rand(1..9) / 10 if digits == 2
+
+          pos = rand(1..digits - 1)
+          precision = digits - pos
+          integers = ''
+          decimals = ''
+          while pos.positive?
+            integers += String(rand(1..9))
+            pos -= 1
+          end
+          while precision.positive?
+            decimals += String(rand(1..9))
+            precision -= 1
+          end
+
+          Float("#{integers}.#{decimals}")
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/random_hexadecimal.rb

@@ -0,0 +1,21 @@
+require 'securerandom'
+
+module Pact
+  module Provider
+    module Generator
+      # RandomHexadecimal provides the random hexadecimal generator which will generate a hexadecimal
+      class RandomHexadecimal
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'RandomHexadecimal'
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          digits = hash['digits'] || 8
+          bytes = (digits / 2).ceil
+          string = SecureRandom.hex(bytes)
+          string[0, digits]
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/random_int.rb

@@ -0,0 +1,18 @@
+module Pact
+  module Provider
+    module Generator
+      # RandomInt provides the random int generator which generate a random integer, with a min/max
+      class RandomInt
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'RandomInt'
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          min = hash['min'] || 0
+          max = hash['max'] || 2_147_483_647
+          rand(min..max)
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/random_string.rb

@@ -0,0 +1,18 @@
+module Pact
+  module Provider
+    module Generator
+      # RandomString provides the random string generator which generate a random string of size length
+      class RandomString
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'RandomString'
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          size = hash['size'] || 20
+          string = rand(36**(size + 2)).to_s(36)
+          string[0, size]
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/regex.rb

@@ -0,0 +1,19 @@
+require 'string_pattern'
+
+module Pact
+  module Provider
+    module Generator
+      # Regex provides the regex generator which will generate a value based on the regex pattern provided
+      class Regex
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'Regex'
+        end
+
+        def call(hash, _params = nil, _example_value = nil)
+          pattern = hash['pattern'] || ''
+          StringPattern.generate(Regexp.new(pattern))
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/time.rb

@@ -0,0 +1,18 @@
+require 'date'
+
+module Pact
+  module Provider
+    module Generator
+      # Time provides the time generator which will give the current time in the defined format
+      class Time < Date
+        def type
+          'Time'
+        end
+
+        def default_format
+          'HH:mm'
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generator/uuid.rb

@@ -0,0 +1,21 @@
+require 'securerandom'
+
+module Pact
+  module Provider
+    module Generator
+      # Uuid provides the uuid generator
+      class Uuid
+        def can_generate?(hash)
+          hash.key?('type') && hash['type'] == 'Uuid'
+        end
+
+        # If we had the example value, we could determine what type of uuid
+        # to send, this is what pact-jvm does
+        # See https://github.com/pact-foundation/pact-jvm/blob/master/core/model/src/main/kotlin/au/com/dius/pact/core/model/generators/Generator.kt
+        def call(_hash, _params = nil, _example_value = nil)
+          SecureRandom.uuid
+        end
+      end
+    end
+  end
+end

lib/pact/provider/generators.rb

@@ -0,0 +1,66 @@
+require 'pact/provider/generator/boolean'
+require 'pact/provider/generator/date'
+require 'pact/provider/generator/datetime'
+require 'pact/provider/generator/provider_state'
+require 'pact/provider/generator/random_decimal'
+require 'pact/provider/generator/random_hexadecimal'
+require 'pact/provider/generator/random_int'
+require 'pact/provider/generator/random_string'
+require 'pact/provider/generator/regex'
+require 'pact/provider/generator/time'
+require 'pact/provider/generator/uuid'
+require 'pact/matching_rules/jsonpath'
+require 'pact/matching_rules/v3/extract'
+require 'jsonpath'
+
+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, state_params = nil, example_value = nil)
+        generators.each do |parser|
+          return parser.call(object, state_params, example_value) if parser.can_generate?(object)
+        end
+
+        raise Pact::UnrecognizePactFormatError, "This document does not use a recognised Pact generator: #{object}"
+      end
+
+      def self.apply_generators(expected_request, component, example_value, state_params)
+        # Latest pact-support is required to have generators exposed
+        if expected_request.methods.include?(:generators) && expected_request.generators[component]
+          # Some component will have single generator without selectors, i.e. path
+          generators = expected_request.generators[component]
+          if generators.is_a?(Hash) && generators.key?('type')
+            return execute_generators(generators, state_params, example_value)
+          end
+
+          generators.each do |selector, generator|
+            val = JsonPath.new(selector).on(example_value)
+            replace = execute_generators(generator, state_params, val)
+            example_value = JsonPath.for(example_value).gsub(selector) { |_v| replace }.to_hash
+          end
+        end
+        example_value
+      end
+
+      add_generator(Generator::Boolean.new)
+      add_generator(Generator::Date.new)
+      add_generator(Generator::DateTime.new)
+      add_generator(Generator::ProviderState.new)
+      add_generator(Generator::RandomDecimal.new)
+      add_generator(Generator::RandomHexadecimal.new)
+      add_generator(Generator::RandomInt.new)
+      add_generator(Generator::RandomString.new)
+      add_generator(Generator::Regex.new)
+      add_generator(Generator::Time.new)
+      add_generator(Generator::Uuid.new)
+    end
+  end
+end