Yeogi-eottae Reduces API Migration Risks by Building a Shadowing Verification Dashboard

The Exhibition Development Team at Yeogi-eottae improved the Shadowing approach and built a dashboard to address verification challenges encountered during the migration from a legacy MongoDB storage to a source data API. Previously, logs had to be analyzed manually, but the new system integrates Grafana, Prometheus, and Loki to visualize match rates, mismatched fields, request reproduction conditions, and the time taken by existing/new logic. Additionally, duplicate code based on annotations and AOP was consolidated into a common library to reduce code volume and ensure consistency. This resulted in a 99.98% match rate across hundreds of thousands of request comparisons and allowed for the early identification of performance differences (new logic being approximately 7ms slower), significantly improving verification efficiency.