Devsisters Introduces JSON Schema Validation and VS Code Autocomplete for Cookie Run: Kingdom Battle Data

Devsisters Studio programmer Kim Yong-wook introduced a JSON Schema-based validation system to solve typos and type errors occurring during the battle data input process for Cookie Run: Kingdom. Previously, planners manually entered data in Excel, but Unity's built-in JSON parser would silently ignore invalid values or cause runtime errors, requiring significant time for debugging.

Automatic JSON Schema Generation and Customization

The development team adopted an approach that automatically generates JSON Schema from C# class definitions. They utilized Json.NET's JSONSchemaGenerator, but applied a post-processing step to resolve the mismatch between PascalCase keys and the camelCase of actual input data, as well as number/string mapping issues for Enum types. Through this, they set additionalProperties to false to block unnecessary field entries, and flexibly adjusted required fields (required) to complete a schema suitable for complex game logic data.

VS Code Integration and Productivity Improvement

The generated JSON Schema is integrated with Visual Studio Code to provide real-time validation and autocomplete features for planners and QA when entering data. Through .vscode/settings.json configuration, the schema is applied to JSON files within specific folders, and frequently used syntax is registered as Code Snippets to improve input efficiency. This system performs validation on a separate thread during every battle test, and as a result, it has increased the speed of content updates and significantly reduced bugs caused by data errors.