Postman_API_Testing_Scripts_And_Validations

Testing API Response Codes:

Testing API Headers:

1. There is a lot of information present in the Headers section but our testing should be testing the "Content-Type".
2. Majorily, what does the "Content-Type" section represent Response Format => JSON, XML, HTML, etc. The format can be (let's say): application/json; which is termed as "mime type". The type of response/data is called mime-type.
3. So, we need to verify if the content type is in JSON Format or not.
4. We can also perform validation on the "Connection" field.
5. We can also perform validation on the "Expires" field.

Testing Cookies:

1. One issue of testing the cookies is that they are prone to change dynamically or their values keep on changing.

2. But there are some cookies whose value won't change each time dynamically. So we can validate those cookies.

3. Assertion => pm.expect(pm.cookies.has('language')).to.be.true;

4. Assertion => pm.expect(pm.cookies.get('language')).to.eql('en-gb');

Testing Response times:

1. As the response time can also vary depending on multiple factors, we try to check if the Response time is under a specified time limit.

Testing Response Body:

1. Asserting if the data types of all fields in the JSON File are correct.

2. Asserting the array properties: Checking if an Array is empty and if it contains particular items:

pm.expect(jsonData.courses).to.include("Java"); pm.expect(jsonData.courses).to.have.members(["Java","Selenium"]);

Validating JSON Fields in Response:

1. The values that are present in the respective fields in Response in the JSON Data file can also be validated: pm.expect(jsonData.id).to.eql(1);

Testing the Pre-Request Scripts along with the Test Scripts at the Collection, Folder, and Request Level as well:

API Chaining Concept:

When we use the Response obtained from an API obtained as a result of some Request sent by the user; as the Request for another/next API; then that is termed as Chaining.

Request1 => API => Response1 => (Response1 = Request2) => Request2 => API2 => Response2

Here; the Response obtained from API1 is sent as a Request for API2