# Storage & Database Map

This page covers the storage module, plugin storage isolation, and database files.

## 1. Main Storage Module (StorageModule)

**Responsibility**: config persistence, cache/LRU, version broadcast, unified read/write.

**Code locations**:
- Entry: `apps/core-app/src/main/modules/storage/index.ts`
- Cache: `apps/core-app/src/main/modules/storage/storage-cache.ts`
- LRU manager: `apps/core-app/src/main/modules/storage/storage-lru-manager.ts`
- Frequency monitor: `apps/core-app/src/main/modules/storage/storage-frequency-monitor.ts`
- Polling service: `apps/core-app/src/main/modules/storage/storage-polling-service.ts`
- Registry: `apps/core-app/src/main/modules/storage/main-storage-registry.ts`

**Common storage entities**:
- `packages/utils/common/storage/`
- `packages/utils/common/storage/entity/`
- `packages/utils/common/storage/constants.ts`

## 2. Plugin Storage Isolation

**Responsibility**: per-plugin isolated config/data (10MB cap) with broadcast sync.

**Code locations**:
- Plugin storage events: `apps/core-app/src/main/modules/plugin/plugin-module.ts`
- Plugin storage bridge: `apps/core-app/src/main/modules/plugin/plugin.ts`
- Event bus marker: `apps/core-app/src/main/core/eventbus/touch-event.ts`

## 3. Database Module (DatabaseModule)

**Responsibility**: structured storage, scheduled writes, retry strategy.

**Code locations**:
- Module entry: `apps/core-app/src/main/modules/database/index.ts`
- Schema: `apps/core-app/src/main/db/schema.ts`
- Write scheduler: `apps/core-app/src/main/db/db-write-scheduler.ts`
- SQLite retry: `apps/core-app/src/main/db/sqlite-retry.ts`
- DB utils: `apps/core-app/src/main/db/utils.ts`

## 4. Storage Update Flow (Mermaid)

:::TuffCodeBlock{lang="mermaid"}
---
code: |
  flowchart LR
    storage["StorageModule"] --> cache["Cache/LRU"]
    storage --> persist["Disk JSON / SQLite"]
    storage --> broadcast["Broadcast Update"]
    broadcast --> renderer["Renderer Windows"]
    broadcast --> plugin["Plugin Storage Listeners"]
---
:::

## 5. Related Docs

- IPC event map: `apps/nexus/content/docs/dev/architecture/transport-events.en.mdc`
- Module overview: `apps/nexus/content/docs/dev/architecture/module-map.en.mdc`