# Property Tax Architecture ### Overview The DIGIT Property Tax module implements a microservices architecture with clearly defined core services, common services, and reusable components. The system follows event-driven patterns using Kafka for asynchronous processing and maintains data consistency through well-defined service interactions. The Property Tax module consists of three main microservices: 1. property services - Legacy property management services 2. pt-services-v2 - Modern property management services 3. pt-calculator-v2 - Billing and tax calculation service ``` property-tax/ ├── property-services/ # Legacy property management service ├── pt-services-v2/ # Modern property management service (V2) └── pt-calculator-v2/ # Billing and tax calculation service (V2) ``` ## 1. **property-services** - Legacy Property Management Service The original property management service that handles comprehensive property data management, including: * Property master data management * Owner and institutional ownership tracking * Property addresses with geolocation support * Unit/floor-level details * Property assessments for each financial year * Document management (property documents, owner documents, assessment documents) * Draft property submissions * Property migration tracking * Data encryption audit trails **Key Features:** * Complete CRUD operations for properties and assessments * Support for both individual and institutional ownership * Multi-unit/floor property support * Comprehensive address management with GPS coordinates * Financial year-based assessments * Full audit trail through dedicated audit tables * Property migration support from legacy systems * Data encryption capabilities ## 2. **pt-services-v2** - Property Management Service V2 Modern redesigned service for property tax management with improved data structure: * Streamlined property registration and management * Enhanced owner information management * Improved address and geolocation tracking * Property detail and assessment management * Unit-level property management * Document management for properties and owners * Institutional ownership support * Draft property submissions * Comprehensive audit trails **Key Features:** * Simplified and efficient data model * JSONB support for flexible additional data * Enhanced indexing for better performance * Support for ad-hoc exemptions and penalties * Improved multi-tenancy support * Financial year-based property details * Annual Rental Value (ARV) tracking * Construction type and usage category management #### 3. **pt-calculator-v2** - Tax Calculation Service V2 Specialised service handling all property tax calculations and billing: * Billing slab configuration based on multiple property parameters * Property tax calculation using configurable rate structures * Mutation fee calculation for ownership transfers * Assessment record management * Dynamic rate determination based on: * Property type and subtype * Usage categories (Major/Minor/Sub-minor/Detail) * Ownership categories * Floor levels * Plot size ranges * Occupancy type * Area type * Market value (for mutation fees) **Key Features:** * Flexible multi-parameter billing slab system * Support for unit rate and ARV percentage-based calculations * Unbuilt land tax calculation * Mutation fee calculation with fixed and percentage methods * Market value-based fee determination * Assessment of demand linking * Tenant-specific rate configuration * Multi-floored property support ## Technology Stack * **Framework:** Spring Boot (Java 8+) * **Database:** PostgreSQL 9.6+ * **Migration Tool:** Flyway * **Data Formats:** JSON/JSONB for flexible data storage * **Architecture:** Microservices-based * **Multi-tenancy:** Supported across all services ## Module Package Structure The Property Tax module follows DIGIT’s layered, event-driven architecture with a clear separation of responsibilities across packages. This makes the codebase easier to understand, navigate, and maintain. Configuration is kept in **config**, business logic in **service**, utilities and constants in **util**, and validations in **validator**. Data access and external integrations are handled by the **repository**, with a **builder** for queries and a **rowmapper** for mapping database results. The **web** layer exposes APIs through **controllers** and defines request/response objects in **models**, while Kafka-based messaging is managed through **consumer** and **producer** packages. ``` config - Contains all the configuration properties related to the module service - Consists of all services containing the business logic. util - Contains utility functions and constants. validator - Contains all validation code repository - Fetch data from dependent micro services repository/rowmapper - Rowmappers to convert db query results to object repository/builder - Contains query builder for search web/controllers - Controllers for the app. web/models - POJO for the module. consumer - Contains all the Kafka consumers, producer - Contains kafka producer ``` The Property Tax Calculator module follows DIGIT’s event-driven microservices architecture. Its package structure separates messaging, data access, business logic, and configuration, making the codebase easier to understand and maintain. Kafka interactions are handled through dedicated **consumers** and **producers**, database access is managed by **repository** and **query-builder** packages, domain data is defined in **models**, and all service and infrastructure settings are grouped under **config**. ``` property-tax-calculator/ ├── consumer/ # Message queue consumers ├── producer/ # Message queue producers ├── repository/ # Data access layer ├── query-builder/ # Query construction utilities ├── models/ # Data models and entities └── config/ # Configuration files ``` ### Core Components The core components encapsulate the key business workflows of the module. Listed below are the key components used by the module. * **Calculator Service:** Implements property tax calculation rules * **Demand Service:** Manages demand creation and updates * **Billing Integration:** Interfaces with the billing service * **Finance Integration:** Posts transactions to the finance system * **Notification Service:** SMS and email notifications to citizens and officials at relevant stages --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.digit.org/local-governance/access/local-governance-stack/property-tax/property-tax-architecture.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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