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Aisalkyn Aidarova
Aisalkyn Aidarova

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LAB 1 — Your FIRST Newman Execution (from zero)

  • Create API test in Postman
  • Export it
  • Run it using Newman

Step 1 — Create Collection in Postman

1. Open Postman

2. Create Collection:

  • Name: devops-newman-lab

3. Add request:

  • Name: Get Users
  • Method: GET
  • URL: 
https://jsonplaceholder.typicode.com/users
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Step 2 — Add Tests (IMPORTANT)

Go to Tests tab and add:

pm.test("Status is 200", function () {
    pm.response.to.have.status(200);
});

pm.test("Response is not empty", function () {
    var jsonData = pm.response.json();
    pm.expect(jsonData.length).to.be.above(0);
});
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Click Send → make sure it passes

Step 3 — Export Collection

  1. Click Collection → ...
  2. Click Export
  3. Save as: 
devops-lab-collection.json
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Step 4 — Install Newman

In your terminal (Mac):

npm install -g newman
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Check:

newman -v
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Step 5 — Run with Newman 

newman run devops-lab-collection.json
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Expected Output 

✔ Status is 200
✔ Response is not empty

2 tests passed
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What you just learned (IMPORTANT)

You:

  • Created API test
  • Automated validation
  • Ran it via CLI

👉 This is exact DevOps behavior

LAB 2 — Add Environment (REAL DEVOPS)

Goal

Remove hardcoding

Step 1 — Create Environment in Postman

Name: dev

Add variable:

KEY VALUE
base_url https://jsonplaceholder.typicode.com

Step 2 — Update Request

Change URL:

{{base_url}}/users
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Test again → should work

Step 3 — Export Environment

Save as:

dev-environment.json
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Step 4 — Run with Newman 

newman run devops-lab-collection.json -e dev-environment.json
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Why this matters

Now:

  • Same test works for dev / stage / prod
  • No hardcoding (like Terraform best practice)

LAB 3 — Add POST Request (REAL FLOW)

Step 1 — Add request

  • Name: Create User
  • Method: POST
  • URL: 
{{base_url}}/users
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Body → JSON: 

{
  "name": "Aisalkyn",
  "job": "DevOps Engineer"
}
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Step 2 — Add Tests 

pm.test("Status is 201", function () {
    pm.response.to.have.status(201);
});

pm.test("User created", function () {
    var jsonData = pm.response.json();
    pm.expect(jsonData.name).to.eql("Aisalkyn");
});
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Step 3 — Export again

Overwrite:

devops-lab-collection.json
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Step 4 — Run Newman 

newman run devops-lab-collection.json -e dev-environment.json
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LAB 4 — Save Data Between Requests (IMPORTANT)

Goal:

Take id from POST → use in GET

Step 1 — In POST Tests: 

let jsonData = pm.response.json();
pm.environment.set("user_id", jsonData.id);
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Step 2 — Add GET request

  • Name: Get User by ID
  • URL: 
{{base_url}}/users/{{user_id}}
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Step 3 — Add test: 

pm.test("User fetched", function () {
    pm.response.to.have.status(200);
});
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Step 4 — Run again 

newman run devops-lab-collection.json -e dev-environment.json
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LAB 5 — DevOps Simulation (Pipeline Style)

Now imagine this runs automatically:

#!/bin/bash

echo "Running API tests..."

newman run devops-lab-collection.json -e dev-environment.json

if [ $? -ne 0 ]; then
  echo "Tests failed. Deployment stopped."
  exit 1
fi

echo "Tests passed. Continue deployment."
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What you learned (BIG PICTURE)

You now know:

  • How DevOps validates APIs
  • How to automate API tests
  • How to remove hardcoding
  • How to chain requests
  • How CI/CD works with APIs

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