feat: set a maximum message length in controller

backend/.env

@@ -6,4 +6,5 @@ FB_PARAMS_AUTH_URI=https://accounts.google.com/o/oauth2/auth
 FB_PARAMS_TOKEN_URI=https://oauth2.googleapis.com/token
 FB_PARAMS_AUTH_PROVIDER_X509_CERT_URL=https://www.googleapis.com/oauth2/v1/certs
 FB_PARAMS_CLIENT_C509_CERT_URL=https://www.googleapis.com/robot/v1/metadata/x509/firebase-adminsdk-j8wbf%40wsne-28b5b.iam.gserviceaccount.com
-MAX_NUMBER_POSTS_PER_DAY=10
+MAX_NUMBER_POSTS_PER_DAY=10
+MAX_MESSAGE_LENGTH=120

backend/src/posts/controller.spec.ts

@@ -20,7 +20,7 @@ describe('Controller', () => {
     s = new Service(collection);
     c = new Controller(s);
     old_env = process.env;
-    process.env = { MAX_NUMBER_POSTS_PER_DAY: '5' };
+    process.env = { MAX_NUMBER_POSTS_PER_DAY: '5', MAX_MESSAGE_LENGTH: '100' };
     jest.spyOn(s, 'countAllforUserByDate').mockResolvedValue(0);
   });
   afterEach(() => {
@@ -89,5 +89,16 @@ describe('Controller', () => {
         ).rejects.toThrow();
       });
     });
+    describe('when the message is too long', () => {
+      it('should throw an error', async () => {
+        await expect(
+          c.create(
+            { user: { user_id: '1234' } },
+            { message: 'test'.repeat(100) },
+          ),
+        ).rejects.toThrow();
+        expect(s.create).not.toHaveBeenCalled();
+      });
+    });
   });
 });

backend/src/posts/controller.ts

@@ -68,6 +68,7 @@ export class Controller {
   ): Promise<ResolvedPostDocument> {
     const { user } = request;
     const { user_id: userId, name: userName } = user;
+
     const last24hours = Date.now() - 86400000;
     const numberPostsCreatedToday = await this.service.countAllforUserByDate(
       userId,
@@ -84,6 +85,14 @@ export class Controller {
           ' posts per day',
       );
     }
+
+    const maxMessageLength = parseInt(process.env.MAX_MESSAGE_LENGTH, 10);
+    if (post.message.length > maxMessageLength) {
+      throw new BadRequestException(
+        'Message is too long. Max length is ' + maxMessageLength,
+      );
+    }
+
     return this.service.create(post.message, userId, userName);
   }
 }