Ben Weese

Testing With Postman: Checking Schema

Schema is something you need to test to make sure when they need a string that it is indeed a string. If you google postman and schema checking you will also find a cool tool called tv4. Do not use this as it is out dated and no longer supported. Please just create a test like below. Also create the jsonData inside the test so it bombs out a single test and not the whole collection when running.

pm.test("Has correct schema", function() {
     let jsonData = pm.response.json()
     pm.expect(jsonData.str)"string", "str not a string and instead is " + jsonData.str);
     pm.expect(jsonData.numArray[0])"number", "numArray[0] not a number and instead is " + jsonData.numArray[0]);
     pm.expect(jsonData.numArray[1])"integer", "numArray[1] not a integer and instead is " + jsonData.numArray[1]);
     pm.expect(jsonData.bool)"boolean", "bool not a boolean and instead is " + jsonData.bool);

You can also output to the console if you would like something added to the log. Below are the different ways you can log to the console.

console.log(); outputs log messages to console; outputs information messages to console
console.warn(); outputs warning messages to console
console.error(); outputs error messages to console

An example is if you are calling a string object instead of a string. There is no or in Chai so you will need to use the below code.

      return s === null || typeof s == 'string'
}, "stringObject is not a string or null")


Postman Quick Reference Guide
Chai Assertion Library
Regex Cheat Sheet
Postman: The Complete Guide on Udemy

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