polaris-core/README.md

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# Polaris-Core Module

The `polaris-core` module contains the fundamental entity definitions, core business logic, and foundational interfaces that power Apache Polaris.

## Overview

`polaris-core` handles:
- Entity Management
- Security & Access Control
- Common Persistence Logic
- Object Storage Integration

## Key Components

### Entity Management
Polaris has several different entities defined in `PolarisEntityType`. You can find their definitions in the package `org.apache.polaris.core.entity`.

### Security & Access Control
Polaris uses a role-based access control (RBAC) model. `PolarisPrivilege` defines the available privileges. The RBAC model is implemented in `PolarisAuthorizer`. For more information on authorization, see the package `org.apache.polaris.core.auth`.

### Common Persistence Logic
To store entities, Polaris provides a persistence layer built upon the `BasePersistence` interface. Common persistence logic is handled in the `org.apache.polaris.core.persistence` package. Implementations are found within [the persistence folder](../persistence).

### Object Storage Integration
Polaris supports multiple object storage providers. `PolarisStorageIntegration` provides an interface for accessing and managing data in object stores. For more information, see the package `org.apache.polaris.core.storage`.

## Usage

The `polaris-core` module is primarily consumed by:
- **API Services** - Management and catalog REST services
- **Runtime Components** - Server and admin tools
- **Persistence Implementations** - Eclipselink, JDBC, etc.