Allow parsing of yml swagger files in rswag-api

rswag-api/lib/rswag/api/middleware.rb

@@ -1,4 +1,5 @@
 require 'json'
+require 'yaml'
 
 module Rswag
   module Api
@@ -14,7 +15,7 @@ module Rswag
         filename = "#{@config.resolve_swagger_root(env)}/#{path}"
 
         if env['REQUEST_METHOD'] == 'GET' && File.file?(filename)
-          swagger = load_json(filename)
+          swagger = parse_file(filename)
           @config.swagger_filter.call(swagger, env) unless @config.swagger_filter.nil?
 
           return [
@@ -29,6 +30,18 @@ module Rswag
 
       private
 
+      def parse_file(filename)
+        if /\.yml$/ === filename
+          load_yaml(filename)
+        else
+          load_json(filename)
+        end
+      end
+
+      def load_yaml(filename)
+        YAML.safe_load(File.read(filename))
+      end
+
       def load_json(filename)
         JSON.parse(File.read(filename))
       end

rswag-api/spec/rswag/api/fixtures/swagger/v1/swagger.yml

@@ -0,0 +1,5 @@
+swagger: '2.0'
+info:
+  title: API V1
+  version: v1
+paths: {}

rswag-api/spec/rswag/api/middleware_spec.rb

@@ -76,6 +76,21 @@ module Rswag
             expect(response[2].join).to include('"host":"tempuri.org"')
           end
         end
+
+        context 'when a path maps to a yaml swagger file' do
+          let(:env) { env_defaults.merge('PATH_INFO' => 'v1/swagger.yml') }
+
+          it 'returns a 200 status' do
+            expect(response.length).to eql(3)
+            expect(response.first).to eql('200')
+          end
+
+          it 'returns contents of the swagger file' do
+            expect(response.length).to eql(3)
+            expect(response[1]).to include( 'Content-Type' => 'application/json')
+            expect(response[2].join).to include('"title":"API V1"')
+          end
+        end
       end
     end
   end