Bruno API Automation: A Comprehensive Guide

The demand for robust and efficient API testing tools has never been higher. Teams are constantly seeking solutions that not only streamline their testing workflows but also integrate seamlessly with their existing development pipelines. Enter Bruno, a modern, open-source API client purpose-built for API testing and automation. Bruno distinguishes itself from traditional tools like Postman by offering a lightweight, local-first approach that prioritizes speed, security, and developer-friendly workflows. Designed to suit both individual testers and collaborative teams, Bruno brings simplicity and power to API automation by combining an intuitive interface with advanced features such as version control integration, JavaScript-based scripting, and command-line execution capabilities.

Unlike cloud-dependent platforms, Bruno emphasizes local-first architecture, meaning API collections and configurations are stored directly on your machine. This approach ensures data security and faster performance, enabling developers to easily sync test cases via Git or other version control systems. Additionally, Bruno offers flexible environment management and dynamic scripting to allow teams to build complex automated API workflows with minimal overhead. Bruno stands out as a compelling solution for organizations striving to modernize their API testing process and integrate automation into CI/CD pipelines. This guide explores Bruno’s setup, test case creation, scripting capabilities, environment configuration, and how it can enhance your API automation strategy.

Before you deep dive into API automation testing, we recommend checking out our detailed blog, which will give you valuable insights into how Bruno can optimize your API testing workflow.

Setting Up Bruno for API Automation

In the following sections, we’ll walk you through everything you need to get Bruno up and running for your API automation needs — from installation to creating your first automated test cases, configuring environment variables, and executing tests via CLI.

Whether you’re automating GET or POST requests, adding custom JavaScript assertions, or managing multiple environments, this guide will show you exactly how to harness Bruno’s capabilities to build a streamlined and efficient API testing workflow.

Install Bruno

• Download Bruno from its official site (bruno.io) or GitHub repository, depending on your OS.
• Follow the installation prompts to set up the tool on your computer.

Creating a Test Case Directory

Begin by launching the Bruno application and setting up a directory for storing test cases.

• 1. Run the Bruno application.
• 2. Create a COLLECTION named Testcase.
• 3. Select the project folder you created as the directory for this COLLECTION.

Writing and Executing Test Cases in Bruno

1. Creating a GET Request Test Case

• Click the ADD REQUEST button under the Testcase COLLECTION.
• Set the request type to GET.
• Name the request GetDemo and set the URL to:

https://jsonplaceholder.typicode.com/posts/1

2. Adding Test Assertions Using Built-in Assert

• Click the Assert button under the GetDemo request.
• Add the following assertions:

• Response status code equals 200.
• The title in the response body contains “provident.”

Click Run in the upper right corner to execute the assertions.

3. Writing Test Assertions Using JavaScript

• Click the Tests button under GetDemo.
• Add the following assertions:

• Response status code equals 201.
• The title in the response body equals “foo.”

Add the following script:

Click Run to verify the assertions.

4. Creating a POST Request Test Case

• Click ADD REQUEST under the Testcase COLLECTION.
• Set the request type to POST.
• Name the request PostDemo and set the URL to:

https://jsonplaceholder.typicode.com/posts

• Click Body and enter the following JSON data:

5. Adding Test Assertions Using Built-in Assert

• Click the Assert button under PostDemo.
• Add the following assertions:

• Response status code equals 201.
• The title in the response body equals “foo.”

Click Run to execute the assertions.

6. Writing Test Assertions Using JavaScript

• Click Tests under PostDemo.
• Add the following script:
test("res.status should be 201", function() {
 const data = res.getBody();
 expect(res.getStatus()).to.equal(201);
});
test("res.body should be correct", function() {
 const data = res.getBody();
 expect(data.title).to.equal('foo');
});

• Click Run to validate assertions.

Executing Two Test Cases Locally

• Click the Run button under the Testcase COLLECTION to execute all test cases.
• Check and validate whether the results match the expected outcomes.

Configuring Environment Variables in Bruno for API Testing

When running API test cases in different environments, modifying request addresses manually for each test case can be tedious, especially when dealing with multiple test cases. Bruno, an API testing tool, simplifies this by providing environment variables, allowing us to configure request addresses dynamically. This way, instead of modifying each test case, we can simply switch environments.

Creating Environment Variable Configuration Files in Bruno

Follow these steps to set up environment variables in Bruno:

1. Open the Environment Configuration Page:

• Click the Environments button under the Testcase COLLECTION to access the environment settings.

2. Create a New Environment:

• Click ADD ENVIRONMENT in the top-right corner.
• Enter a name for the environment (e.g., dev) and click SAVE to create the configuration file.

3. Add an Environment Variable:

• Select the newly created environment (dev) to open its configuration page.
• Click ADD VARIABLE in the top-right corner.
• Enter the variable name as host and set the value to https://jsonplaceholder.typicode.com.
• Click SAVE to apply the changes.

Using Environment Variables in Test Cases

Instead of hardcoding URLs in test cases, use {{host}} as a placeholder. Bruno will automatically replace it with the configured value from the selected environment, making it easy to switch between different testing environments.

By utilizing environment variables, you can streamline your API testing workflow, reducing manual effort and enhancing maintainability.

Using Environment Variables in Test Cases

Once environment variables are configured in Bruno, we can use them in test cases instead of hardcoding request addresses. This makes it easier to switch between different testing environments without modifying individual test cases.

Modifying Test Cases to Use Environment Variables

1. Update the GetDemo Request:

• Click the GetDemo request under the Testcase COLLECTION to open its editing page.
• Modify the request address to {{host}}/posts/1.
• Click SAVE to apply the changes.

2. Update the PostDemo Request:

• Click the PostDemo request under the Testcase COLLECTION to open its editing page.
• Modify the request address to {{host}}/posts.
• Click SAVE to apply the changes.

Debugging Environment Variables

• Click the Environments button under the Testcase COLLECTION and select the dev environment.
• Click the RUN button in the top-right corner to execute all test cases.
• Verify that the test results meet expectations.

Conclusion

Bruno is a lightweight and powerful tool designed for automating API testing with ease. Its local-first approach, Git-friendly structure, JavaScript-based scripting, and environment management make it ideal for building fast, secure, and reliable API tests. While Bruno streamlines automation, partnering with Codoid can help you take it further. As experts in API automation, Codoid provides end-to-end solutions to help you design, implement, and scale efficient testing frameworks integrated with your CI/CD pipelines. Reach out to Codoid today to enhance your API automation strategy and accelerate your software delivery.

Frequently Asked Questions

The post Bruno API Automation: A Comprehensive Guide appeared first on Codoid.

Source: Read More