feat: return the latest notification on empty result

Author: Ido Shamun

src/models/notification.js

@@ -4,11 +4,16 @@ const table = 'notifications';
 
 const get = (since) => {
   const select = db.select().from(table);
-  const query = since ? select.where('timestamp', '>=', since) : select;
+  const query = since ? select.where('timestamp', '>', since) : select;
   return query.orderBy('timestamp', 'ASC').limit(5).map(toCamelCase);
 };
 
+const getLatest = () =>
+  db.select().from(table).orderBy('timestamp', 'DESC').limit(1)
+    .map(toCamelCase)
+    .then(res => (res.length ? res[0] : null));
+
 const add = obj => db.insert(toSnakeCase(obj)).into(table)
   .then(() => obj);
 
-export default { get, add };
+export default { get, getLatest, add };

src/routes/notifications.js

@@ -16,10 +16,16 @@ router.get(
     },
   }),
   async (ctx) => {
-    const model = await notification.get(ctx.request.query.since);
+    const latestPromise = notification.getLatest();
+    const since = await notification.get(ctx.request.query.since);
 
     ctx.status = 200;
-    ctx.body = model;
+    if (since.length) {
+      ctx.body = since;
+    } else {
+      const latest = await latestPromise;
+      ctx.body = latest ? [latest] : [];
+    }
   },
 );
 

test/integration/models/notification.js

@@ -28,4 +28,11 @@ describe('notification model', () => {
     const model = await notification.get(new Date(2017, 10, 21, 15, 58, 0));
     expect(model).to.deep.equal(fixture.slice(2, 7));
   });
+
+  it('should fetch latest notification', async () => {
+    await Promise.all(fixture.map(n => notification.add(n)));
+
+    const model = await notification.getLatest();
+    expect(model).to.deep.equal(fixture[fixture.length - 1]);
+  });
 });

test/integration/routes/notifications.js

@@ -53,4 +53,13 @@ describe('notifications routes', () => {
 
     expect(body).to.deep.equal(fixture.slice(2, 7).map(mapDate));
   });
+
+  it('should return latest notification', async () => {
+    const { body } = await request
+      .get('/v1/notifications')
+      .query({ since: (new Date(2017, 10, 21, 19, 23, 5)).toISOString() })
+      .expect(200);
+
+    expect(body).to.deep.equal(fixture.slice(6, 7).map(mapDate));
+  });
 });