Architecture Improvements [MYSQL + POSTGRESQL DB SUPPORT]

[Denes-cilwal]

This pull request introduces support for PostgreSQL as a database option in addition to MySQL, refactoring the database connection logic to use a provider-based architecture. The changes improve modularity and future extensibility, allowing easy addition of new database types. The most important changes are grouped below:

Database provider architecture:

• Added a new DBProvider interface and provider factory in pkg/infrastructure/db_provider.go, enabling dynamic selection of MySQL or PostgreSQL based on the DB_TYPE environment variable.
• Implemented MySQLProvider and PostgresProvider in separate files (pkg/infrastructure/mysql_provider.go and pkg/infrastructure/postgres_provider.go) to encapsulate connection logic for each database type. [1] [2]
• Refactored pkg/infrastructure/database_factory.go to use the provider pattern for database creation, replacing direct instantiation with provider-based construction.

PostgreSQL support:

• Added PostgreSQL connection logic in pkg/infrastructure/db.go, including database existence checks and dynamic SSL mode selection.
• Updated Go module dependencies (go.mod) to include gorm.io/driver/postgres and adjust indirect dependencies for both MySQL and PostgreSQL. [1] [2] [3]

Configuration and integration:

• Updated .env.example to document support for both MySQL and PostgreSQL in the DB_TYPE variable.
• Registered the new provider and database constructors in the Fx dependency injection module (pkg/infrastructure/module.go).
• Added the PostgreSQL driver import in pkg/infrastructure/db.go.… support

[Copilot]

Pull Request Overview

This PR refactors the database connection logic to support multiple database providers (MySQL and PostgreSQL) through a provider pattern, replacing the monolithic MySQL-only implementation.

• Introduced a DBProvider interface with MySQL and PostgreSQL implementations
• Refactored database connection logic to use dependency injection via the provider pattern
• Added PostgreSQL driver support alongside the existing MySQL driver

Reviewed Changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
pkg/infrastructure/db_provider.go	Defines the DBProvider interface and factory function for selecting the appropriate database provider based on configuration
pkg/infrastructure/postgres_provider.go	Implements the DBProvider interface for PostgreSQL connections
pkg/infrastructure/mysql_provider.go	Implements the DBProvider interface for MySQL connections
pkg/infrastructure/database_factory.go	Provides Fx constructors for dependency injection of database providers and connections
pkg/infrastructure/db.go	Refactored connection logic into separate MySQLConnect and PostgresConnect functions with proper error handling
pkg/infrastructure/module.go	Registers the new NewDBProvider constructor in the Fx module
go.mod	Promotes gorm.io/driver/postgres from indirect to direct dependency and moves go-sql-driver/mysql to indirect
go.sum	Updates checksums for new and modified dependencies
.env.example	Documents postgres as a supported DB_TYPE option

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[Copilot]

@Denes-cilwal I've opened a new pull request, #127, to work on those changes. Once the pull request is ready, I'll request review from you.

[paudelgaurav]

Closes #120

[Denes-cilwal]

This branch provides support for both MySQL and PostgreSQL.
Use the existing implementation as a reference for MySQL, while the PostgreSQL support has been newly introduced in the develop branch.