Start collecting suite of request/response validation examples

spec/examples.yaml

@@ -0,0 +1,26 @@
+- description: nullable array items in response body
+  oad:
+    openapi: 3.0.3
+    info:
+      title: Response Validation Middleware Example
+      version: 1.0.0
+    paths:
+      /:
+        get:
+          responses:
+            '200':
+              content:
+                application/json:
+                  schema:
+                    properties:
+                      path:
+                        type: array
+                        items:
+                          type: string
+                          nullable: true
+  valid_response:
+    content_type: application/json
+    body: { "path": ["1", "2", null] }
+  invalid_response:
+    content_type: application/json
+    body: { "path": ["1", "2", 3] }

spec/examples_spec.rb

@@ -0,0 +1,86 @@
+# frozen_string_literal: true
+
+require 'rack/test'
+require_relative 'spec_helper'
+
+RSpec.describe 'request/response validation examples' do
+  include Rack::Test::Methods
+
+  # Load all examples from the YAML file
+  examples = YAML.load_file(File.join(__dir__, 'examples.yaml'))
+
+  examples.each do |example|
+    context example['description'] do
+      let(:oad) { example['oad'] }
+      let(:definition) { OpenapiFirst.parse(oad) }
+
+      let(:app) do
+        lambda do |_env|
+          body = if response['body'].is_a?(String)
+                   response['body']
+                 else
+                   JSON.generate(response['body'])
+                 end
+          [
+            response['status'] || 200,
+            { 'Content-Type' => response['content_type'] || 'application/json' },
+            [body]
+          ]
+        end
+      end
+
+      # Get the first path from the OAD
+      let(:test_path) do
+        oad['paths'].keys.first
+      end
+
+      # Get the HTTP method for the test path
+      let(:test_method) do
+        oad['paths'][test_path].keys.first.upcase
+      end
+
+      if example['valid_response']
+        context 'with valid response' do
+          let(:response) { example['valid_response'] }
+
+          it 'passes validation' do
+            send(test_method.downcase, test_path)
+
+            request = Rack::Request.new(last_request.env)
+            body = last_response.body.is_a?(String) ? last_response.body : last_response.body.join
+            response = Rack::Response.new(
+              body,
+              last_response.status,
+              last_response.headers
+            )
+
+            validated = definition.validate_response(request, response)
+            expect(validated).to be_valid
+          end
+        end
+      end
+
+      if example['invalid_response']
+        context 'with invalid response' do
+          let(:response) { example['invalid_response'] }
+
+          it 'fails validation' do
+            send(test_method.downcase, test_path)
+
+            request = Rack::Request.new(last_request.env)
+            body = last_response.body.is_a?(String) ? last_response.body : last_response.body.join
+            response = Rack::Response.new(
+              body,
+              last_response.status,
+              last_response.headers
+            )
+
+            validated = definition.validate_response(request, response)
+            expect(validated).not_to be_valid
+            expect(validated.error).not_to be_nil
+          end
+        end
+      end
+    end
+  end
+end