Write tests for data types in Insomnia

Before you create a test, you need to create a test suite for your API Collection.

1. If your API Collection doesn’t have a Tests tab, go to Preferences > General > Application and enable Show legacy unit tests.
2. On the API Collection screen, click the Tests tab.
3. In the sidebar, click New test suite.

Now we can test if a data type is returned in the top-level request body.

1. Click New test and enter a name for the test, such as “Data type in body (top-level)”.
2. From the Select a request drop down, select the GET KongAir planned flights request.
3. Enter the following JavaScript to check if an array is present in the top-level body of the response:

   const response1 = await insomnia.send();
   const body = JSON.parse(response1.data);
   expect(body).to.be.an('array');

   Copied!
4. Click the Play icon next to the test. In the preview to the right, you should see that the test passes.

Now you can test if a data type is returned in the top-level request body.

1. Click New test and enter a name for the test, such as “Data type in body (nested)”.
2. From the Select a request drop down, select the GET Fetch more details about a flight request.
3. Enter the following JavaScript to check if the first string in the meal_options array is present in the body of the response:

   const response1 = await insomnia.send();
   const body = JSON.parse(response1.data);
   expect(body).to.be.an('object');
   expect(body).to.have.property('meal_options'); 
   expect(body.meal_options).to.be.an('array');
   if (body.meal_options.length > 0) {
       expect(body.meal_options[0]).to.be.a('string');
   }

   Copied!
4. Click the Play icon next to the test. In the preview to the right, you should see that the test passes.