Add FileSystem driver with one JSON file per table

[Copilot]

Implements a file-based persistence driver where each ObjectQL object type is stored as a separate JSON file (e.g., users.json, projects.json).

Implementation

New Package: @objectql/driver-fs

• Storage model: Array of records per file with atomic writes (temp file + rename)
• Backup strategy: Auto-generated .bak files on write operations
• Cache layer: In-memory cache for reads, flush on disconnect
• Query support: Full filter/sort/pagination via in-memory evaluation
• ID generation: Timestamp + counter (configurable via data.id field)
• Initial data support: Pre-populate data on initialization via initialData config
• Utility methods: clear(), clearAll(), invalidateCache(), getCacheSize()

Usage

import { FileSystemDriver } from '@objectql/driver-fs';

const driver = new FileSystemDriver({
    dataDir: './data',
    prettyPrint: true,    // Human-readable JSON
    enableBackup: true,   // Create .bak files
    initialData: {        // Optional: pre-populate data
        users: [
            { id: 'admin', name: 'Admin User', role: 'admin' }
        ]
    }
});

const app = new ObjectQL({
    datasources: { default: driver }
});

File Format

// data/projects.json
[
  {
    "id": "PROJ-001",
    "name": "Website Redesign",
    "status": "in_progress",
    "created_at": "2024-01-16T12:00:00.000Z",
    "updated_at": "2024-01-16T12:00:00.000Z"
  }
]

Test Coverage

• 36 tests covering CRUD, bulk operations, query filters, edge cases, and new features
• Working example in examples/drivers/fs-demo
• Zero security vulnerabilities (CodeQL scan)

Documentation

• Complete English documentation (README.md)
• Chinese documentation (README.zh-CN.md)
• Comprehensive API examples and usage patterns

Limitations

Not recommended for:

• Datasets > 10k records per object (full file rewrite on update)
• Multi-process concurrent writes (no external locking)
• Production high-traffic scenarios (use SQL/MongoDB drivers)

Original prompt

写一个基于文件系统的启动，每张表一个json文件

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[Copilot]

Pull request overview

This PR introduces a new file-based persistence driver (@objectql/driver-fs) for ObjectQL that stores each object type as a separate JSON file, providing a lightweight alternative to traditional database drivers for development and small-scale applications.

Changes:

• Implements a complete FileSystem driver with atomic write operations, backup support, and in-memory caching
• Adds comprehensive test coverage (29 test cases) for CRUD operations, query filters, bulk operations, and edge cases
• Includes a working example demonstrating real-world usage with projects management

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/drivers/fs/src/index.ts	Core driver implementation with full Driver interface support and query operations
packages/drivers/fs/test/index.test.ts	Comprehensive test suite covering CRUD, queries, bulk operations, and file system behavior
packages/drivers/fs/package.json	Package configuration with workspace dependencies
packages/drivers/fs/tsconfig.json	TypeScript configuration for the driver package
packages/drivers/fs/jest.config.js	Jest test configuration with module mapping
packages/drivers/fs/README.md	Complete documentation with examples, API reference, and usage guidelines
packages/drivers/fs/CHANGELOG.md	Initial release changelog
examples/drivers/fs-demo/src/index.ts	Demo application showing practical usage patterns
examples/drivers/fs-demo/package.json	Demo package configuration
examples/drivers/fs-demo/tsconfig.json	TypeScript configuration for demo
examples/drivers/fs-demo/README.md	Demo documentation and usage instructions
examples/drivers/fs-demo/.gitignore	Excludes runtime-generated data directory

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

[huangyiirene]

@copilot 审查代码并修复，更新文档

[Copilot]

@copilot 审查代码并修复，更新文档

代码已审查并改进完成（commit: 55465cf）：

新增功能：

• ✅ initialData 配置选项 - 初始化时预加载数据
• ✅ clear(objectName) - 清除特定对象的所有数据
• ✅ clearAll() - 清除所有对象的数据
• ✅ invalidateCache() - 强制重新加载缓存
• ✅ getCacheSize() - 获取缓存大小

改进：

• ✅ 增强的错误处理（处理无效 JSON 和空文件）
• ✅ 新增中文文档（README.zh-CN.md）
• ✅ 修复 TypeScript 编译配置
• ✅ 新增 7 个测试用例（共 36 个测试，全部通过）
• ✅ 更新了 CHANGELOG 和文档

所有测试通过 ✓