Command	Usage
newman run <file_path>	This command is used to execute API tests which we have exported to our local system
newman run <Collection_file_path_here> -e <environment_file_path_here>	Executes a collection in a specified environment
newman run <Collection_file_path_here> -g <path>	This command is used to run API tests and apply global variables used in that collection
newman run <file_path> -n<number_of_iterations>	Used to run the collection n times
newman run <file_path> –delay-request <time_of_delay>	Used to Configure delay time in between requests

Running Collections with Global and Local Environments

Step 1: Follow the same above-mentioned steps additionally you need to download the global environment to your local system before exporting the environment make sure that the variable value is in ‘initial value’ and on the right corner you see the option ‘Export’ as shown in the image and simply click on that the environment will be downloaded to your local system.

Step 2: After that run the below command in your terminal to run the API request and you can see that the API request is successfully executed as shown below.

newman run <Collection_file_path_her> -g <global_environment_file_path_here>

Step 3: The same goes for the local environment. Download the local environment as shown below:

Step 4. Run the below command in your terminal to run the API request and you can see that the API request is successfully executed as shown below:

newman run <Collection_file_path_her> -e <environment_file_path_here>

Automating Postman Tests with Continuous Integration using Jenkins

Step 1: First make sure your system has Jenkins installed if not install Jenkins by using this guide. Then start the Jenkins server by running the below command and make sure you are in the correct directory before running the command.

java -jar Jenkins.war –httpPort=8080

Step 2: Open up your browser to open http://localhost:8080/ and enter your credentials and click on ‘+ New Item’ and enter the name as per your requirement for this we can go with the freestyle project as shown below and click on OK it takes a few seconds to create a project.

Step 3: On the next page just scroll down to the build section and under build steps click on ‘Add build step’ and choose ‘Execute Windows batch command’ as shown below:

Step 4: Enter the newman run command as given in the below format make sure that the path from your local system is copied correctly and click on save to save the command.

newman run <File_Path_here>

Step 5: Just click on ‘Build Now’ and it takes time to build the project and you can see the output under the Console Output as shown below:

Troubleshooting and Best Practices

1. While writing the command in the Jenkins project make sure that you copy the correct path of the file and write it else at the stage of building your project you will not get the expected output.
2. Double-check all file paths (i.e., collection, environment, global environment) used in the Newman command’s incorrect path may lead to errors.
3. If your collection uses environment or global variables, confirm they are properly defined and exported.
4. You can include logging commands like -r cli,json to note detailed results for analysis and a y troubleshooting issues.
5. Keep your postman collection and scripts under version control to track the changes and ensure consistency across builds and regularly review your automated tests to ensure optimized performance.

Conclusion

In conclusion, running Postman scripts from the Newman CLI command provides an efficient way to automate the testing of APIs and also it enables the developers/users to execute the API test collection without the need for GUI (Graphical User Interface).