A leading investment management firm, providing solutions to institutions, financial professionals, and millions of individuals worldwide, faces a critical challenge. They must ensure consistent API functionality across various environments where both legacy and current API versions are deployed. To maintain reliability and performance, it is essential to compare the responses from these APIs and identify any discrepancies promptly.

The client is one of the largest investment management firms globally, catering to institutions, financial professionals, and millions of individuals. They require reliable solutions to maintain consistent API performance and data integrity across various deployment environments.

• Data Discrepancies: Differences in responses between legacy and current APIs.
• Manual Monitoring Effort: High manual effort is required to monitor differences when the same APIs are deployed in different environments without automated tests.
• Functionality Loss: Potential loss of functionality in new API versions post-migration.

To address these challenges, we employed GemPyp, a robust test automation framework, to streamline the process of comparing a current API's behavior against a legacy API. The approach includes the following steps:

XML Configuration Files:

• Define details of both the current and legacy APIs, including URLs, methods, headers, expected status codes, and key verification checks.

Response Key Verification:

• Ensure essential data points are present in responses from both APIs.
• Use JSON (dot notation) or list structures (bracket notation with indexing) for syntax.

Enhanced Comparison:

• Perform detailed comparisons beyond key verification.
• Compare response keys to values, keys between APIs, or even perform cell-by-cell comparisons (optional).

Integration with Reporting Tools:

• Generate comprehensive reports highlighting discrepancies between the current API's behavior and the legacy API's expected behavior.
• Facilitate swift issue identification and resolution.

• Improved Reliability: Ensures APIs perform consistently across different environments, reducing the risk of unexpected behavior in production.
• Efficient Migration: Facilitates smooth migration by validating that new API versions retain the same functionality as the older versions.
• Data Accuracy: Maintains data integrity by identifying discrepancies between legacy and current API responses.
• Reduced Manual Effort: Automated testing minimizes manual intervention, saving time and effort for the development and QA teams.
• Comprehensive Reporting: Detailed reports provide insights into API data and issues, enabling quick resolution.