file-browser/README.md

# Nextcloud + Elasticsearch Discovery File Explorer

A discovery-first file explorer built with Next.js (App Router, TypeScript, Tailwind, shadcn UI) that connects to Nextcloud via WebDAV and indexes metadata/content into Elasticsearch (BM25 baseline, optional semantic hybrid search). Includes upload/download, folder tree browsing, global search, and Sentry instrumentation.

## TL;DR (Quick Start)

Prereqs:
- Node 18+ and npm
- Docker (for Elasticsearch/Kibana/Tika services)

Setup:
1) Configure environment
   - Copy `.env.example` to `.env.local` and fill in your values (Nextcloud creds + Elasticsearch endpoint).
   - A pre-populated `.env.local` is included for your provided Nextcloud host (update if needed).

2) Provision Elasticsearch + Tika (Docker sample below)
3) Create Elasticsearch index
   - `npm run create:index`
4) Ingest Nextcloud into ES (BM25 baseline)
   - `npx tsx -r dotenv/config -r tsconfig-paths/register scripts/ingest-nextcloud.ts`
5) Run the app
   - `npm run dev` then open the reported URL (e.g., http://localhost:3000)

## Why this exists

Nextcloud is the system of record for files; this app provides a discovery UX (fast search, filters, previews later) by indexing normalized documents into Elasticsearch. Apache Tika can extract plain text for rich BM25 search, and optional OpenAI-compatible embeddings enable semantic hybrid search.

## Architecture

- UI: Next.js App Router (TypeScript), Tailwind CSS, shadcn UI
- Data
  - Nextcloud WebDAV for browse/upload/download
  - Elasticsearch for indexing and search (BM25 baseline)
  - Apache Tika server for content extraction (optional but recommended)
  - OpenAI-compatible embeddings (optional) for dense vectors/hybrid queries
- Observability: Sentry (client/server/edge) with logs and spans

## Features

- Browse Nextcloud directories via a lazy-loading sidebar tree
- View files with size/type and actions in a table
- Upload files into the current folder
- Download/proxy via Next.js route
- Global search box (BM25 baseline) with optional “Semantic” toggle for hybrid search (when embeddings are configured)
- Sentry logging/tracing sprinkled around WebDAV and Elasticsearch calls

## Project Layout (highlights)

- src/lib
  - env.ts: zod-validated env loader with flags
  - paths.ts: normalization/helpers for DAV paths
  - elasticsearch.ts: ES client, ensureIndex, bm25Search, knnSearch, hybridSearch
  - webdav.ts: Nextcloud WebDAV wrapper (list/create/upload/download/stat) with spans
  - embeddings.ts: OpenAI-compatible embeddings client
- src/app/api
  - folders/list, folders/create
  - files/list, files/upload, files/download
  - search/query
- scripts
  - create-index.ts: creates ES index + alias
  - ingest-nextcloud.ts: crawl Nextcloud → optional Tika → index into ES
- docs/elasticsearch/mappings.json: canonical baseline mapping
- Sentry init
  - instrumentation-client.ts, sentry.server.config.ts, sentry.edge.config.ts

## Environment Variables

Populate `.env.local` (not committed). See `.env.example` for full list.

Required:
- NEXTCLOUD_BASE_URL: e.g. https://your-nextcloud.example.com
- NEXTCLOUD_USERNAME: WebDAV user
- NEXTCLOUD_APP_PASSWORD: App password generated in Nextcloud (not login password)
- NEXTCLOUD_ROOT_PATH: e.g. `/remote.php/dav/files/admin`

- ELASTICSEARCH_URL: e.g. http://localhost:9200
- ELASTICSEARCH_INDEX: default `files`
- ELASTICSEARCH_ALIAS: default `files_current`

Optional:
- TIKA_BASE_URL: e.g. http://localhost:9998 (if using Apache Tika for extraction)
- SENTRY_DSN: if provided, Sentry is enabled
- OPENAI_API_BASE, OPENAI_API_KEY, OPENAI_EMBEDDING_MODEL, EMBEDDING_DIM: Enable embeddings + semantic hybrid

## Dependencies and Local Services (Docker)

Below is a sample docker-compose for local development. Adjust versions for your environment. For TrueNAS Scale, translate this into an appropriate app configuration.

```yaml
version: "3.9"
services:
  elasticsearch:
    image: docker.elastic.co/elasticsearch/elasticsearch:8.12.2
    container_name: es
    environment:
      - discovery.type=single-node
      - xpack.security.enabled=false
      - ES_JAVA_OPTS=-Xms1g -Xmx1g
    ports:
      - "9200:9200"
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:9200/_cluster/health"]
      interval: 10s
      timeout: 5s
      retries: 10

  kibana:
    image: docker.elastic.co/kibana/kibana:8.12.2
    container_name: kibana
    environment:
      - ELASTICSEARCH_HOSTS=http://elasticsearch:9200
    ports:
      - "5601:5601"
    depends_on:
      elasticsearch:
        condition: service_healthy

  tika:
    image: apache/tika:latest-full
    container_name: tika
    ports:
      - "9998:9998"
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:9998"]
      interval: 10s
      timeout: 5s
      retries: 10
```

Notes:
- Security is relaxed in this dev config (xpack security disabled). Harden for production.
- Set `TIKA_BASE_URL=http://localhost:9998` to enable content extraction.

## Install & Run

Install dependencies:

```bash
npm install
```

Run development server:

```bash
npm run dev
# Next.js will print the URL, for example http://localhost:3000
```

Build and start:

```bash
npm run build
npm start
```

## Initialize Elasticsearch

Create the index and alias (files/files_current):

```bash
npm run create:index
# internally: tsx -r dotenv/config -r tsconfig-paths/register scripts/create-index.ts
```

To recreate:
```bash
npm run create:index -- --recreate
```

## Ingest Nextcloud → Elasticsearch

Crawl Nextcloud via WebDAV, optionally extract content with Tika, index into ES:

```bash
npx tsx -r dotenv/config -r tsconfig-paths/register scripts/ingest-nextcloud.ts
```

Restrict to a subtree:
```bash
npx tsx -r dotenv/config -r tsconfig-paths/register scripts/ingest-nextcloud.ts -- --root=/remote.php/dav/files/admin/SomeFolder
```

After ingestion, try searching in the UI (BM25).

## Optional: Semantic Hybrid Search

To enable, configure embeddings:
- OPENAI_API_BASE (e.g., https://api.openai.com/v1 or your compatible endpoint)
- OPENAI_API_KEY
- OPENAI_EMBEDDING_MODEL (e.g., text-embedding-3-large)
- EMBEDDING_DIM (e.g., 1536)

Current code path supports:
- Hybrid search in API when `semantic: true` in requests; UI has a “Semantic” toggle.
- A future backfill script can be added to compute vectors for existing docs (planned).

## Sentry

- Files:
  - instrumentation-client.ts (client init)
  - sentry.server.config.ts (node runtime)
  - sentry.edge.config.ts (edge runtime)
- Enable by setting SENTRY_DSN in `.env.local`.
- Logging enabled (`consoleLoggingIntegration`), capturing console.log/warn/error.
- Spans instrument WebDAV and ES operations with meaningful op/name and attributes.

## API Endpoints

- GET `/api/folders/list?path=/abs/path` → { folders[], files[] }
- POST `/api/folders/create` body: `{ path: "/abs/path" }` → `{ ok: true }`
- GET `/api/files/list?path=/abs/path&page=1&perPage=50` → `{ total, page, perPage, items[] }`
- POST `/api/files/upload` (multipart) form-data: `file`, `destPath`
- GET `/api/files/download?path=/abs/path` → stream download
- POST `/api/search/query` → body: `{ q, filters?, sort?, page?, perPage?, semantic? }`

## UI Usage

- Navigate folders via the left sidebar. Root defaults to `NEXTCLOUD_ROOT_PATH`.
- Breadcrumbs show the current path; click to navigate.
- Global search queries ES (BM25). Toggle “Semantic” to blend vector similarity (when enabled).
- Use “Upload” to send a file to the current folder.
- Click a file name or download action to retrieve it.

## Known Caveats / TODO

- When starting from `NEXTCLOUD_ROOT_PATH`, breadcrumb segments may include technical path prefixes (e.g., `/remote.php`, `/dav`) that aren’t browsable independently. This can be adjusted to start breadcrumbs from the user root only.
- Embeddings backfill script & “Find similar” API/UI are planned.
- Tests (unit/integration/E2E) and TrueNAS-specific compose notes can be added next.

## Development Notes

- Code style: TypeScript, ESLint (Next config), Tailwind v4.
- shadcn components added (Slate), most primitives included.
- ES Types via `@elastic/elasticsearch` estypes.
- Stream interop handled for Node → Web streams in downloads and uploads.
- Zod-based env loader normalizes URLs and validates required vars.

## Troubleshooting

- Search 500s:
  - Ensure Elasticsearch is running and reachable at `ELASTICSEARCH_URL`.
  - Run `npm run create:index` to create the index and alias.
  - If using Tika for content, ensure `TIKA_BASE_URL` is set and service is healthy (optional).
- WebDAV failures:
  - Verify `NEXTCLOUD_BASE_URL`, `NEXTCLOUD_USERNAME`, `NEXTCLOUD_APP_PASSWORD`, and `NEXTCLOUD_ROOT_PATH`.
  - Confirm the user has permission for the target path.
- Sentry issues:
  - Ensure `SENTRY_DSN` is set; check networking/outbound restrictions.

## Scripts

- `npm run create:index`: Create/recreate Elasticsearch index and alias
- `scripts/ingest-nextcloud.ts`: Crawl Nextcloud → Tika (optional) → Elasticsearch

## Security

- Keep `.env.local` out of source control (already in .gitignore).
- Use Nextcloud App Passwords, not login passwords.
- Harden Elasticsearch/Kibana/Tika for production (auth, TLS, resource limits).

---

Built per implementation_plan.md with a deterministic order of rollout and Sentry instrumentation aligned to organizational rules.