Difference between REST Assured and Postman Runner

REST Assured and Postman Runner are both tools used for API testing but differ in their approach and features:

REST Assured

1. Type:

   • Library: REST Assured is a Java-based library for testing RESTful APIs directly within Java code.

2. Features:

   • Declarative Syntax: REST Assured uses a fluent and declarative syntax, making it easy to construct requests, specify assertions, and validate responses in Java.
   • Integration: Seamlessly integrates with popular Java testing frameworks like JUnit and TestNG, allowing API tests to be part of automated test suites.
   • Automation: Suitable for automating API tests as part of Continuous Integration (CI) pipelines using tools like Maven or Gradle.
   • Assertion Libraries: Provides built-in assertion capabilities for validating response content, headers, status codes, etc., without needing additional tools or environments.

3. Use Cases:

   • Best suited for Java-based projects or teams familiar with Java programming.
   • Ideal for integrating API tests directly into existing Java test suites and automation frameworks.
   • Provides flexibility and control over API testing logic within Java code.

Postman Runner

1. Type:

   • Application: Postman Runner is a standalone application used for testing APIs via a graphical user interface (GUI).

2. Features:

   • GUI Interface: Postman provides a user-friendly interface for creating, organizing, and executing API requests and collections.
   • Collections: Allows grouping of API requests into collections, enabling sequential or parallel execution of requests with pre-defined variables and environments.
   • Automation: Supports automation through the use of collections and Newman (Postman’s command-line tool), enabling API tests to be run in CI/CD pipelines.
   • Environment Variables: Supports managing environment-specific variables for different stages (e.g., development, testing, production) within collections.

3. Use Cases:

   • Suitable for teams and individuals who prefer a visual, non-programmatic approach to API testing.
   • Useful for manual exploratory testing, creating and sharing API documentation, and collaborating on API workflows.
   • Provides a comprehensive ecosystem with features beyond testing, such as monitoring, mocking, and API documentation generation.

Comparison

• Programming Language: REST Assured is Java-based and requires Java programming knowledge, whereas Postman Runner provides a GUI for creating and managing API requests without requiring programming skills.

• Automation: REST Assured is integrated directly into Java test frameworks for automated testing, while Postman Runner supports automation through collections and Newman, suitable for integrating with CI/CD pipelines.

• Flexibility vs. Ease of Use: REST Assured offers flexibility and control through Java code but requires programming skills, while Postman Runner offers ease of use with a visual interface but may have limitations in complex test scenarios or customizations.

Choosing Between REST Assured and Postman Runner

• Development Environment: Choose REST Assured for Java-based projects where API testing needs to be tightly integrated with existing Java codebases and automation frameworks.

• Ease of Use: Choose Postman Runner for teams or individuals preferring a graphical interface, quick setup, and collaboration features without the need for extensive programming knowledge.

• Integration: Consider Postman Runner if you need features beyond testing, such as API monitoring, documentation, and sharing collections across teams.