# UnifiedFiler v2.0 Notes

v2.0 is the first stable API release of UnifiedFiler as a Host-embedded File Operation Control Framework.

## Highlights

- Public API version fixed as `2.0`
- Package version updated to `2.0.0`
- Stable Host-facing Control contract documented
- Stable extension contracts documented for:
  - Command
  - Create Type
  - Preview Provider
  - Storage Adapter
  - Backend API
  - Security Policy
- Added `PublicApiContractService`
- Added `RegressionTestService`
- Added top-level helpers on `UnifiedFiler/main`:
  - `create()`
  - `createControl()`
  - `createExplorer()`
  - `createPicker()`
  - `createSaver()`
  - `openPicker()`
  - `openSaver()`
  - `getPublicApiContract()`
  - `runRegressionTests()`
- Added shared `UnifiedFilerControl.registerCreateType()` / `registerCreateTypes()` / `unregisterCreateType()` for future Explorer children
- Added browser demo for lightweight v2.0 contract regression tests

## Non-goals

v2.0 does not introduce a backend server requirement. Google Drive remains frontend-only.

## Recommended Host integration entry

```javascript
require(['UnifiedFiler/main'], function (UnifiedFiler) {
    var filer = UnifiedFiler.create({ language: 'ja' });
    var explorer = filer.createExplorer('#host', { defaultStorage: 'appStorage' });
});
```

## Stability note

Internal View classes under `scripts/views/` remain public for advanced diagnostics and composition, but Host applications should prefer the Control APIs for normal integration.