Continuous Integration (CI) is a development practice where developers integrate code into a shared repository frequently, ideally several times a day. Each integration can then be verified by an automated build and automated tests. This section will guide you through integrating Postman tests into a CI pipeline, ensuring that your API tests are automatically executed whenever changes are made to the codebase.

1. Continuous Integration (CI):

   • A practice that involves automatically testing and building code changes.
   • Helps in identifying issues early in the development process.

2. Postman and CI:

   • Postman tests can be integrated into CI pipelines using Newman, Postman's command-line collection runner.
   • Automates the execution of Postman tests as part of the CI process.

3. Newman:

   • A command-line tool that allows you to run Postman collections.
   • Can be integrated with various CI/CD tools like Jenkins, Travis CI, CircleCI, etc.

To run Postman collections in your CI pipeline, you need to install Newman. You can do this using npm (Node Package Manager).

1. Open Postman and navigate to the collection you want to test.
2. Click on the "..." next to the collection name and select "Export".
3. Save the exported file in a location accessible by your CI server.

Create a command to run your Postman collection using Newman. This command will be used in your CI pipeline.

Example: Jenkins

1. Install Node.js and Newman on Jenkins:

   • Ensure Node.js is installed on your Jenkins server.
   • Install Newman globally using npm.

2. Create a Jenkins Job:

   • Go to Jenkins dashboard and create a new Freestyle project.
   • In the "Build" section, add a "Execute shell" build step.
   • Enter the Newman command to run your Postman collection.

3. Configure Triggers:

   • Set up triggers to run the job automatically when changes are pushed to the repository.

Example: Travis CI

1. Add a .travis.yml File:

2. Push Changes:
   • Commit and push the .travis.yml file to your repository.
   • Travis CI will automatically run the tests on each push.

Exercise: Integrate a Postman collection into a CI pipeline using Travis CI.

1. Export a Postman collection from your Postman workspace.
2. Create a new GitHub repository and add the exported collection.
3. Add a .travis.yml file to the repository with the necessary configuration to run Newman.
4. Push the changes and observe the Travis CI build process.

Solution:

1. Export the collection as my-collection.json.
2. Create a new repository and add my-collection.json.
3. Add the following .travis.yml file:

4. Push the changes and check the Travis CI dashboard for the build status.

• Incorrect File Paths: Ensure the path to your Postman collection in the Newman command is correct.
• Environment Variables: If your collection uses environment variables, export and include them in the Newman command.
• CI Tool Configuration: Double-check the configuration of your CI tool to ensure it triggers builds correctly.

Integrating Postman tests into a CI pipeline enhances the reliability of your API testing by ensuring tests are run automatically with every code change. This practice helps catch issues early and maintain the quality of your APIs. In the next section, we will explore how to use Mock Servers in Postman to simulate API responses.