Verify Newman installation and version

Preconditions (2)

Step 1: Open the command line interface

Step 2: Run the command 'npm install -g newman' to install Newman globally

Step 3: Wait for the installation to complete

Step 4: Run the command 'newman -v' to check the installed Newman version

✅ Expected Result: Newman installs successfully without errors and the version number is displayed correctly

Automation Requirements - Node.js with child_process module

Assertions Needed:

Verify that 'npm install -g newman' command completes without errors

Verify that 'newman -v' command outputs a valid version string

Best Practices:

Use child_process.exec to run CLI commands asynchronously

Check for errors in command execution

Validate output format with regex for version number

Use clear and descriptive assertion messages

Automated Solution

Postman

import { exec } from 'child_process';

function runCommand(command) {
  return new Promise((resolve, reject) => {
    exec(command, (error, stdout, stderr) => {
      if (error) {
        reject(new Error(`Command failed: ${command}\n${stderr}`));
      } else {
        resolve(stdout.trim());
      }
    });
  });
}

(async () => {
  try {
    console.log('Installing Newman globally...');
    const installOutput = await runCommand('npm install -g newman');
    console.log('Installation output:', installOutput);

    console.log('Checking Newman version...');
    const versionOutput = await runCommand('newman -v');
    console.log('Newman version:', versionOutput);

    const versionRegex = /^\d+\.\d+\.\d+$/;
    if (!versionRegex.test(versionOutput)) {
      throw new Error('Newman version output is not a valid version string');
    }

    console.log('Test passed: Newman installed and version verified successfully.');
  } catch (error) {
    console.error('Test failed:', error.message);
    process.exit(1);
  }
})();

This script uses Node.js child_process.exec to run shell commands asynchronously.

First, it runs npm install -g newman to install Newman globally. It waits for the command to finish and checks for errors.

Next, it runs newman -v to get the installed version. It verifies the output matches a version pattern like 1.2.3.

If any command fails or the version output is invalid, the script throws an error and exits with failure.

This approach ensures the installation and version check are automated and validated properly.

Common Mistakes - 3 Pitfalls

Not checking for errors after running the install command

Assuming the version output is always valid without validation

Running commands synchronously blocking the event loop

Bonus Challenge

Now add data-driven testing to install Newman with different npm versions and verify installation each time

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