Thread by @irtimid_harding

💡JavaScript for QA💡

Did you know that you could execute JavaScript in #Postman?

- before your request 🚀
- after your response 🛬

Read this thread to know more👇🏾 [1/10]

From their website - "𝘗𝘰𝘴𝘵𝘮𝘢𝘯 𝘤𝘰𝘯𝘵𝘢𝘪𝘯𝘴 𝘢 𝘱𝘰𝘸𝘦𝘳𝘧𝘶𝘭 𝘳𝘶𝘯𝘵𝘪𝘮𝘦 𝘣𝘢𝘴𝘦𝘥 𝘰𝘯 𝘕𝘰𝘥𝘦.𝘫𝘴 𝘵𝘩𝘢𝘵 𝘢𝘭𝘭𝘰𝘸𝘴 𝘺𝘰𝘶 𝘵𝘰 𝘢𝘥𝘥 𝘥𝘺𝘯𝘢𝘮𝘪𝘤 𝘣𝘦𝘩𝘢𝘷𝘪𝘰𝘳 𝘵𝘰 𝘳𝘦𝘲𝘶𝘦𝘴𝘵𝘴 𝘢𝘯𝘥 𝘤𝘰𝘭𝘭𝘦𝘤𝘵𝘪𝘰𝘯𝘴." [2/10]

In these examples, we are using the famous console.log in the Pre-request Script and Tests tab

Look at the third picture, to see the console output after we make the request. [3/10]

Let us create an API test that will take a dynamic cost param, and we'll assert that the response had that same value.

🌟Pre-Request Script🌟
- 1. Use Math JavaScript object to generate a random number
- 2. Postman environmental variable to save the value for later
[4/10]

In the previous tweet, we created a random cost environmental variable, now we can use that in our request.

🌟Request🌟
- 1. Let the cost param in our request use the `cost` environmental variable - using {{cost}} [5/10]

Now we need to assert once the response returns.

🌟Tests🌟
- 1. Use the pm.test function to create a test
- 2. Get the cost environment variable-expected value
- 3. Get the response using `pm.response.json()`-actual value
- 4. Compare actual and expected [6/10]

Let's run out the test, and see what happens.🧐

🚨Results🚨
- 1. The test failed, since the API returned cost as a string but our actual cost is a number
- 2. We did note that the two values were 77 (both actual and expected)
- 3. This could be a 🐛...👀 [7/10]

✅ We dynamically created a random cost using JavaScript in our Pre-Request script

✅ Then use that value in our Request

✅ And finally used that to assert something in our response.

🎉 Where we potentially found an issue. Should cost be a string or an integer? [8/10]

📝 In closing, JavaScript is baked in a lot of tools that QA uses on a daily

Understanding JavaScript can be very helpful/beneficial, especially if you want to #LevelUpYourAutomation [9/10]

❓Let me know if this tweet was helpful. Did you learn anything? Have a great day!