fix: parse query string to hash for v2 interactions

Fixes: pact-foundation/pact-mock_service#80

Author: bethesque

lib/pact/consumer_contract/interaction_v2_parser.rb

@@ -1,6 +1,7 @@
 require 'pact/consumer_contract/request'
 require 'pact/consumer_contract/response'
 require 'pact/consumer_contract/provider_state'
+require 'pact/consumer_contract/query'
 require 'pact/symbolize_keys'
 require 'pact/matching_rules'
 require 'pact/errors'
@@ -15,13 +16,17 @@ def self.call hash, options
       response = parse_response(hash['response'], options)
       provider_states = parse_provider_states(hash['providerState'] || hash['provider_state'])
       metadata = parse_metadata(hash['metadata'])
-      Interaction.new(symbolize_keys(hash).merge(request: request, 
-                                                 response: response, 
+      Interaction.new(symbolize_keys(hash).merge(request: request,
+                                                 response: response,
                                                  provider_states: provider_states,
                                                  metadata: metadata))
     end
 
     def self.parse_request request_hash, options
+      if request_hash['query'].is_a?(String)
+        request_hash = request_hash.dup
+        request_hash['query'] = Pact::Query.parse_string(request_hash['query'])
+      end
       request_hash = Pact::MatchingRules.merge(request_hash, request_hash['matchingRules'], options)
       Pact::Request::Expected.from_hash(request_hash)
     end

lib/pact/consumer_contract/query.rb

@@ -3,12 +3,110 @@
 
 module Pact
   class Query
+    DEFAULT_SEP = /[&;] */n
+    COMMON_SEP = { ";" => /[;] */n, ";," => /[;,] */n, "&" => /[&] */n }
+
     def self.create query
       if query.is_a? Hash
         Pact::QueryHash.new(query)
       else
         Pact::QueryString.new(query)
       end
     end
+
+    def self.parse_string query_string
+      parsed_query = parse_query(query_string)
+
+      # If Rails nested params...
+      if parsed_query.keys.any?{ | key| key.include?("[") }
+        parse_nested_query(query_string)
+      else
+        parsed_query.each_with_object({}) do | (key, value), new_hash |
+          new_hash[key] = [*value]
+        end
+      end
+    end
+
+    # Ripped from Rack to avoid adding an unnecessary dependency, thank you Rack
+    # https://github.com/rack/rack/blob/649c72bab9e7b50d657b5b432d0c205c95c2be07/lib/rack/utils.rb
+    def self.parse_query(qs, d = nil, &unescaper)
+      unescaper ||= method(:unescape)
+
+      params = {}
+
+      (qs || '').split(d ? (COMMON_SEP[d] || /[#{d}] */n) : DEFAULT_SEP).each do |p|
+        next if p.empty?
+        k, v = p.split('=', 2).map!(&unescaper)
+
+        if cur = params[k]
+          if cur.class == Array
+            params[k] << v
+          else
+            params[k] = [cur, v]
+          end
+        else
+          params[k] = v
+        end
+      end
+
+      return params.to_h
+    end
+
+    def self.parse_nested_query(qs, d = nil)
+      params = {}
+
+      unless qs.nil? || qs.empty?
+        (qs || '').split(d ? (COMMON_SEP[d] || /[#{d}] */n) : DEFAULT_SEP).each do |p|
+          k, v = p.split('=', 2).map! { |s| unescape(s) }
+
+          normalize_params(params, k, v)
+        end
+      end
+
+      return params.to_h
+    end
+
+    def self.normalize_params(params, name, v)
+      name =~ %r(\A[\[\]]*([^\[\]]+)\]*)
+      k = $1 || ''
+      after = $' || ''
+
+      if k.empty?
+        if !v.nil? && name == "[]"
+          return Array(v)
+        else
+          return
+        end
+      end
+
+      if after == ''
+        params[k] = v
+      elsif after == "["
+        params[name] = v
+      elsif after == "[]"
+        params[k] ||= []
+        raise ParameterTypeError, "expected Array (got #{params[k].class.name}) for param `#{k}'" unless params[k].is_a?(Array)
+        params[k] << v
+      elsif after =~ %r(^\[\]\[([^\[\]]+)\]$) || after =~ %r(^\[\](.+)$)
+        child_key = $1
+        params[k] ||= []
+        raise ParameterTypeError, "expected Array (got #{params[k].class.name}) for param `#{k}'" unless params[k].is_a?(Array)
+        if params_hash_type?(params[k].last) && !params_hash_has_key?(params[k].last, child_key)
+          normalize_params(params[k].last, child_key, v)
+        else
+          params[k] << normalize_params({}, child_key, v)
+        end
+      else
+        params[k] ||= {}
+        raise ParameterTypeError, "expected Hash (got #{params[k].class.name}) for param `#{k}'" unless params_hash_type?(params[k])
+        params[k] = normalize_params(params[k], after, v, depth - 1)
+      end
+
+      params
+    end
+
+    def self.unescape(s, encoding = Encoding::UTF_8)
+      URI.decode_www_form_component(s, encoding)
+    end
   end
 end

spec/lib/pact/consumer_contract/interaction_v2_parser_spec.rb

@@ -49,6 +49,21 @@ module Pact
           expect(subject.provider_state).to eq "foo"
         end
       end
+
+      describe "query" do
+        let(:interaction_hash) do
+          {
+            "description" => "description",
+            "request" => { "method" => "GET", "path" => "/", "query" => "foo=bar1&foo=bar2"},
+            "response" => { "status" => 200 },
+            "providerState" => "foo"
+          }
+        end
+
+        it "parses a string query into a hash" do
+          expect(subject.request.query).to eq Pact::QueryHash.new("foo"=> [ "bar1", "bar2" ])
+        end
+      end
     end
   end
 end

spec/lib/pact/consumer_contract/query_spec.rb

@@ -0,0 +1,33 @@
+require 'pact/consumer_contract/query'
+
+module Pact
+  describe Query do
+    describe ".parse_string" do
+      subject { Query.parse_string(query_string) }
+
+      describe "with a non nested query string" do
+        let(:query_string) { "foo=bar1" }
+
+        it "returns a map of string to array" do
+          expect(subject).to eq "foo" => ["bar1"]
+        end
+      end
+
+      describe "with a non nested query string with multiple params with the same name" do
+        let(:query_string) { "foo=bar1&foo=bar2" }
+
+        it "returns a map of string to array" do
+          expect(subject).to eq "foo" => ["bar1", "bar2"]
+        end
+      end
+
+      describe "with a rails style nested query" do
+        let(:query_string) { "foo=bar1&foo=bar2&baz[]=thing1&baz[]=thing2" }
+
+        it "returns a nested map" do
+          expect(subject).to eq "foo" => "bar2", "baz" => ["thing1", "thing2"]
+        end
+      end
+    end
+  end
+end