Posted on Oct 21, 2020

Write Negative API Tests

So far we have written all the positive/happy path test scenarios, in this post, we'll take a look at how we can write a few negative API tests to ensure our APIs are secure and functioning as they should.

Let's take a look at some examples -

Unauthenticated Test
Create a test to ensure the user cannot hit the APIs without being properly authenticated.

it('401 Authentication Failed', async () => { // sending request without the Authentication Token const postRes = await request.post('posts').send(data); expect(postRes.body.code).to.eq(401); expect(postRes.body.data.message).to.eq('Authentication failed'); });

Validation Failed
Create a test to ensure the user should not be able to create data without passing in the required fields.

it('422 Validation Failed', async () => { // 'body' is a required field which is not being passed with the data const data = { user_id: userId, title: 'My title', }; const postRes = await request .post('posts') .set('Authorization', `Bearer ${TOKEN}`) .send(data); expect(postRes.body.code).to.eq(422); expect(postRes.body.data[0].field).to.eq('body'); expect(postRes.body.data[0].message).to.eq("can't be blank"); });