Newman in CI/CD pipelines in Postman - Build an Automation Script

Run Postman collection using Newman in CI/CD pipeline

Preconditions (3)

Step 1: Configure the CI/CD pipeline to include a step to run Newman

Step 2: Use the command: newman run <collection-file.json> -e <environment-file.json>

Step 3: Execute the pipeline

Step 4: Observe the output logs for test run results

✅ Expected Result: Newman runs the Postman collection successfully, all tests pass, and the pipeline logs show a summary of the test results

Automation Requirements - Newman CLI

Assertions Needed:

Verify that Newman command exits with status code 0 indicating success

Verify that the test summary shows all tests passed

Verify that the pipeline logs contain the expected test run output

Best Practices:

Use explicit exit code checks to determine pass/fail

Use environment variables for collection and environment file paths

Integrate Newman command in a script step in the CI/CD pipeline configuration

Capture and parse Newman JSON report for detailed assertions if needed

Automated Solution

Postman

import subprocess
import json

# Paths to collection and environment files
collection_file = 'postman_collection.json'
environment_file = 'postman_environment.json'

# Run Newman command with JSON reporter
command = [
    'newman', 'run', collection_file,
    '-e', environment_file,
    '--reporters', 'cli,json',
    '--reporter-json-export', 'newman_report.json'
]

result = subprocess.run(command, capture_output=True, text=True)

# Check exit code
assert result.returncode == 0, f"Newman run failed with exit code {result.returncode}"

# Load JSON report
with open('newman_report.json') as f:
    report = json.load(f)

# Check all tests passed
assert report['run']['stats']['failed'] == 0, "Some tests failed in Newman run"

print("Newman run successful: all tests passed.")

This script runs the Newman CLI command using Python's subprocess module. It specifies the collection and environment files, and requests both CLI and JSON reports.

After running, it checks the exit code to confirm the run was successful.

Then it loads the JSON report file and asserts that zero tests failed.

This ensures the CI/CD pipeline can detect failures and pass/fail accordingly.

Common Mistakes - 3 Pitfalls

Not checking the exit code of the Newman command

Hardcoding file paths inside the script

Not using explicit reporters like JSON for parsing results

Bonus Challenge

Now add data-driven testing by running the same Postman collection with three different environment files in the CI/CD pipeline.

Show Hint

Practice

1. What is the main purpose of using Newman in a CI/CD pipeline?

easy

A. To write new API tests inside Postman

B. To run Postman API tests automatically from the command line

C. To deploy applications to production servers

D. To monitor server performance in real-time

Solution

1. Step 1: Understand Newman's role

   Newman is a command-line tool designed to run Postman API tests outside the Postman app.

2. Step 2: Connect to CI/CD pipeline use

   In CI/CD pipelines, Newman automates running these tests to check API health during builds or deployments.

3. Final Answer:

   To run Postman API tests automatically from the command line -> Option B

4. Quick Check:

   Newman runs tests in CI/CD = C [OK]

Hint: Newman runs Postman tests from command line in pipelines [OK]

Common Mistakes:

• Confusing Newman with deployment tools
• Thinking Newman writes tests instead of running them
• Assuming Newman monitors servers

2. Which of the following is the correct basic syntax to run a Postman collection using Newman?

easy

A. newman run collection.json

B. newman execute collection.json

C. newman start collection.json

D. newman test collection.json

Solution

1. Step 1: Recall Newman command structure

   The correct command to run a collection is 'newman run' followed by the collection file.

2. Step 2: Verify options

   Options like 'execute', 'start', or 'test' are not valid Newman commands.

3. Final Answer:

   newman run collection.json -> Option A

4. Quick Check:

   Correct Newman run syntax = D [OK]

Hint: Use 'newman run' to execute collections [OK]

Common Mistakes:

• Using 'execute' or 'start' instead of 'run'
• Omitting the 'run' keyword
• Confusing Newman commands with other tools

3. What will be the output when running this command in a CI pipeline?

newman run mycollection.json --reporters cli,json --reporter-json-export result.json

medium

A. Runs tests and outputs results only in CLI, no file created

B. Runs tests and saves results only in XML format

C. Runs tests but fails due to invalid reporter options

D. Runs tests, shows CLI output, and saves JSON report to result.json

Solution

1. Step 1: Analyze reporter options

   The command uses '--reporters cli,json' to show results in CLI and JSON format.

2. Step 2: Check JSON export flag

   '--reporter-json-export result.json' saves the JSON report to the file 'result.json'.

3. Final Answer:

   Runs tests, shows CLI output, and saves JSON report to result.json -> Option D

4. Quick Check:

   CLI + JSON report saved = B [OK]

Hint: Multiple reporters show CLI and save JSON report [OK]

Common Mistakes:

• Assuming no file is created
• Thinking JSON export is invalid syntax
• Confusing JSON with XML report format

4. You added this command in your CI pipeline:

newman run collection.json --reporters cli --reporter-json-export report.json

But the JSON report file is not created. What is the likely problem?

medium

A. The CLI reporter disables file exports

B. The collection.json file is missing

C. Missing 'json' in the --reporters option

D. Newman does not support JSON reports

Solution

1. Step 1: Check reporter options consistency

   The command uses '--reporters cli' but tries to export JSON report, which requires 'json' reporter enabled.

2. Step 2: Understand reporter behavior

   Without 'json' in '--reporters', the JSON export flag is ignored, so no file is created.

3. Final Answer:

   Missing 'json' in the --reporters option -> Option C

4. Quick Check:

   JSON export needs 'json' reporter = A [OK]

Hint: Include 'json' in --reporters to export JSON files [OK]

Common Mistakes:

• Assuming collection file missing causes no report
• Thinking CLI reporter blocks file exports
• Believing Newman can't export JSON reports

5. In a CI/CD pipeline, you want to fail the build if any Postman test fails using Newman. Which command option helps achieve this?

hard

A. --bail

B. --fail-fast

C. --exit-on-error

D. --stop-on-failure

Solution

1. Step 1: Identify Newman option for failure control

   The '--bail' option stops the run and returns a failure exit code if any test fails.

2. Step 2: Confirm other options

   Options like '--fail-fast', '--exit-on-error', and '--stop-on-failure' are not valid Newman flags.

3. Final Answer:

   --bail -> Option A

4. Quick Check:

   Fail build on test failure = --bail [OK]

Hint: Use '--bail' to stop and fail on test errors [OK]

Common Mistakes:

• Using non-existent flags like --fail-fast
• Not using any fail option, so build passes despite failures
• Confusing '--bail' with report generation options