From bccf173544a639f38949cad93e343831ea9874eb Mon Sep 17 00:00:00 2001
From: Carmine DiMascio <cdimascio@tripadvisor.com>
Date: Wed, 15 Jan 2020 20:52:26 -0500
Subject: [PATCH] empty response passes response check #219

---
 src/middlewares/openapi.response.validator.ts |  9 +++++
 test/resources/response.validation.yaml       | 14 ++++++++
 test/response.validation.spec.ts              | 36 +++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/src/middlewares/openapi.response.validator.ts b/src/middlewares/openapi.response.validator.ts
index c64d37cb..b4709cfb 100644
--- a/src/middlewares/openapi.response.validator.ts
+++ b/src/middlewares/openapi.response.validator.ts
@@ -104,6 +104,9 @@ export class ResponseValidator {
       // assume valid
       return;
     }
+    if (!body) {
+      throw validationError(500, '.response', 'response body required.');
+    }
     const valid = validator({
       response: body,
     });
@@ -127,6 +130,9 @@ export class ResponseValidator {
     responses: OpenAPIV3.ResponsesObject,
   ): { [key: string]: ajv.ValidateFunction } {
     const canValidate = response => {
+      if (!response.content) {
+        return 'no_content';
+      }
       if (typeof response.content !== 'object') {
         return false;
       }
@@ -157,6 +163,9 @@ export class ResponseValidator {
         // don't validate
         // assume is valid
         continue;
+      } else if (mediaTypeToValidate === 'no_content') {
+        schemas[name] = {};
+        continue;
       }
       const schema = response.content[mediaTypeToValidate].schema;
 
diff --git a/test/resources/response.validation.yaml b/test/resources/response.validation.yaml
index 7cc88841..574ed4e5 100644
--- a/test/resources/response.validation.yaml
+++ b/test/resources/response.validation.yaml
@@ -14,6 +14,20 @@ info:
 servers:
   - url: /v1
 paths:
+  /empty_response:
+    description: get empty response
+    summary: get empty response
+    get:
+      description: get empty response
+      operationId: get empty resp
+      parameters:
+        - name: mode
+          in: query
+          schema:
+            type: string
+      responses:
+        '200':
+          description: empty
   /pets:
     description: endpoints for pets
     summary: endpoints for pets
diff --git a/test/response.validation.spec.ts b/test/response.validation.spec.ts
index bb0d44b6..6fa5fa90 100644
--- a/test/response.validation.spec.ts
+++ b/test/response.validation.spec.ts
@@ -19,6 +19,9 @@ describe(packageJson.name, () => {
       },
       3005,
       app => {
+        app.get(`${app.basePath}/empty_response`, (req, res) => {
+          return res.end();
+        });
         app.get(`${app.basePath}/users`, (req, res) => {
           const json = ['user1', 'user2', 'user3'];
           return res.json(json);
@@ -38,7 +41,12 @@ describe(packageJson.name, () => {
               },
               { id: 3, name: 'name', tag: 'tag' },
             ];
+          } else if (req.query.mode === 'empty_object') {
+            json = {};
+          } else if (req.query.mode === 'empty_response') {
+            return res.json();
           }
+
           return res.json(json);
         });
         app.post(`${app.basePath}/no_additional_props`, (req, res) => {
@@ -70,6 +78,34 @@ describe(packageJson.name, () => {
           .that.equals(500);
       }));
 
+  it('should fail if response is response is empty object', async () =>
+    request(app)
+      .get(`${app.basePath}/pets?mode=empty_object`)
+      .expect(500)
+      .then((r: any) => {
+        console.log(r.body);
+        expect(r.body.message).to.contain('should be array');
+        expect(r.body)
+          .to.have.property('code')
+          .that.equals(500);
+      }));
+
+  it('should fail if response is response is empty', async () =>
+    request(app)
+      .get(`${app.basePath}/pets?mode=empty_response`)
+      .expect(500)
+      .then((r: any) => {
+        expect(r.body.message).to.contain('body required');
+        expect(r.body)
+          .to.have.property('code')
+          .that.equals(500);
+      }));
+
+  it('should return 200 for endpoints that return empty response', async () =>
+    request(app)
+      .get(`${app.basePath}/empty_response`)
+      .expect(200));
+
   it('should fail if additional properties are provided when set false', async () =>
     request(app)
       .post(`${app.basePath}/no_additional_props`)