Meta-Fuse
Standalone virtual filesystem service that exposes metadata-organized content via FUSE and WebDAV without duplicating files.
Overview
Meta-Fuse is a read-only process in the MetaMesh ecosystem that:
- Locates meta-core over UDP - beacon v2 multicast advertise (
239.255.99.1:9099); no shared volume, noREDIS_URL - Reads metadata through meta-core's HTTP API -
/meta/{hash}*reads + SSE live updates on/api/events/meta(no direct Redis access) - Mounts virtual filesystem - Rust-based FUSE driver creates an organized view of media files
- Serves WebDAV - Network-accessible, read-only file sharing for Windows/Mac/Linux clients, authenticated with per-device tokens
- Zero file duplication - File bytes are read from meta-core's WebDAV (
http://<meta-core host>/webdav), which also covers SMB/rclone mounts; no/filesmount required - Configurable renaming rules - Virtual paths are computed from metadata by editable rules (dashboard rules editor)
Architecture
┌─────────────────────────────────────────────────────────────────────────────┐
│ MetaMesh Ecosystem │
├─────────────────────────────────────────────────────────────────────────────┤
│ │
│ meta-core (owns Redis) │
│ ┌──────────────────────────────────────────────┐ │
│ │ UDP announce (beacon v2, /urls) │ │
│ │ HTTP API: /meta/{hash}*, /api/events/meta │ │
│ │ WebDAV: /webdav (file bytes, /files/...) │ │
│ └──────────────────────────────────────────────┘ │
│ ▲ metadata (HTTP + SSE) ▲ file bytes (WebDAV Range) │
│ ┌────────┴────────────────────────────────┴───────────────────┐ │
│ │ META-FUSE │ │
│ │ ┌─────────────────────────────────────────────────────────┐│ │
│ │ │ Storage client (KVManager / LeaderClient) ││ │
│ │ │ - Locates meta-core via UDP (or META_CORE_URL pin) ││ │
│ │ │ - Reads metadata over HTTP, events over SSE ││ │
│ │ │ - Reconnects when a different meta-core announces ││ │
│ │ └─────────────────────────────────────────────────────────┘│ │
│ │ │ │ │
│ │ ┌─────────────┴─────────────┐ │ │
│ │ ▼ ▼ │ │
│ │ ┌───────────────────────┐ ┌─────────────────────────┐ │ │
│ │ │ FUSE API Server │ │ WebDAV Server │ │ │
│ │ │ (Node.js/Fastify) │ │ (WsgiDAV, token auth)│ │ │
│ │ │ Port 3000 │ │ Port 8080 │ │ │
│ │ └───────────┬───────────┘ └───────────┬─────────────┘ │ │
│ │ │ │ │ │
│ │ ▼ │ │ │
│ │ ┌───────────────────────┐ │ │ │
│ │ │ FUSE Driver │◄──────────────┘ │ │
│ │ │ (Rust) │ │ │
│ │ │ /mnt/virtual │ │ │
│ │ └───────────────────────┘ │ │
│ └─────────────────────────────────────────────────────────────┘ │
│ │ │
│ ▼ │
│ ┌─────────────────────────┐ │
│ │ nginx (port 80) │ │
│ │ / → UI │ │
│ │ /webdav → WebDAV │ │
│ │ /api/ → API │ │
│ │ /health → API │ │
│ └─────────────────────────┘ │
│ │ │
└────────────────────────────┼────────────────────────────────────────────────┘
▼
External Clients
(Windows/Mac/Linux)
In the dev stack and the CasaOS store app (packages/MetaAppStore, app MetaFuse) the backend runs as metafuse-app behind an OIDC perimeter container metafuse (nginx-hash-lock in dev, appshield in the store app); in the store app Caddy routes /health and /webdav* straight to the backend, so WebDAV is authenticated by WebDAV tokens instead. See the meta-root authentication architecture.
Service Role in MetaMesh
┌────────────────────────────────────────────────────────────────────────────┐
│ SERVICE ROLES │
├────────────────────────────────────────────────────────────────────────────┤
│ │
│ [1] meta-core (STORE) │
│ └─► Owns Redis, metadata HTTP API, event streams, WebDAV over /files │
│ │
│ [2] meta-sort (PROCESS-WRITE) │
│ └─► Watches folders, writes metadata through meta-core │
│ │
│ [3] meta-fuse (PROCESS-READ) ◄── YOU ARE HERE │
│ └─► Reads metadata from meta-core, exposes virtual filesystem │
│ │
│ [4] meta-stremio (PROCESS-READ) │
│ └─► Reads metadata, streams media content │
│ │
└────────────────────────────────────────────────────────────────────────────┘
Locating meta-core (beacon v2)
meta-core announces itself on UDP multicast 239.255.99.1:9099, carrying its /urls payload. meta-fuse listens (and announces itself on the same group, so it shows up in every neighbour's nav menu):
/urls payload (JSON):
{
"hostname": "metacore-app",
"baseUrl": "https://metacore-dev.localhost:8083",
"apiUrl": "http://<meta-core ip>:9000",
"redisUrl": "", # always empty since the api-mediated-access lockdown
"webdavUrl": "https://metacore-dev.localhost:8083/webdav",
"webdavUrlInternal": "http://<meta-core ip>:9000/webdav"
}
Discovery flow:
1. meta-core advertises `metamesh.core` with its /urls payload (`data.urls`)
2. meta-fuse picks it up (or uses META_CORE_URL and GET {url}/urls when pinned)
3. meta-fuse reads metadata from apiUrl (/meta/{hash}*) and streams apiUrl/api/events/meta
4. File bytes are fetched from http://<hostname>/webdav
5. An announce carrying a different apiUrl triggers a reconnect
Note: meta-fuse never owns storage. If meta-core still publishes a non-empty redisUrl, meta-fuse refuses to start (set ALLOW_LEGACY_REDIS_URL=1 to downgrade that to a warning). Protocol spec: beacon-v2.md.
Core Features
Virtual Filesystem (FUSE)
- Organized view: Files appear in categorized folders (Movies, TV, Anime, etc.)
- Path-to-inode mapping: Translates filesystem paths to FUSE inode numbers
- Attribute caching: 1-second TTL for file attributes
- Directory caching: 30-second TTL for directory listings
- Error resilience: Virtual
ERROR.txtshown after 3 consecutive API failures - WebDAV reads: The driver issues HTTP Range requests against the
webdavUrlreturned by/api/fuse/read
WebDAV Server
- Network file sharing: Mount as network drive on any OS
- Read-only access: Prevents accidental modifications
- Per-device tokens: Minted/revoked from the dashboard (
/api/webdav-tokens); the token (mfwd_…) is the basic-auth password, any non-empty username is accepted. Only sha256 hashes are stored ($CONFIG_DIR/webdav-tokens.json); revocation is immediate - Directory browsing: Web-based file browser
Renaming Rules
- Stored in
$CONFIG_DIR/renaming-rules.json(timestamped backups on update) - Template variables + conditions; preview and validate via the API before saving
- Only the metadata properties the rules reference are fetched (
RulesPropertyExtractor)
Package Structure
meta-fuse/
├── packages/
│ ├── meta-fuse-core/ # Core service (@meta-fuse/core)
│ │ ├── src/
│ │ │ ├── api/APIServer.ts # Fastify REST API
│ │ │ ├── config/ConfigStorage.ts # Renaming-rules persistence
│ │ │ ├── discovery/meshdisco.ts # beacon v2 (mirrored, see scripts/check-mirrors.sh)
│ │ │ ├── kv/ # Storage client (read-only)
│ │ │ │ ├── IKVClient.ts # Read-only interface
│ │ │ │ ├── KVManager.ts # meta-core location, connection management
│ │ │ │ ├── LeaderClient.ts # Adapter over MetaCoreLocator (UDP / META_CORE_URL pin)
│ │ │ │ ├── MetaCoreApiClient.ts # HTTP reads: /meta, /meta/{hash}, /meta/{hash}/{prop}
│ │ │ │ ├── SSEEventClient.ts # SSE consumer for /api/events/meta
│ │ │ │ └── RedisClient.ts # Storage facade (HTTP-only mode when redisUrl is empty)
│ │ │ ├── vfs/ # Virtual filesystem logic
│ │ │ │ ├── VirtualFileSystem.ts # In-memory VFS representation
│ │ │ │ ├── StreamingStateBuilder.ts # Event-driven state management
│ │ │ │ ├── RulesPropertyExtractor.ts # Property filtering from rules
│ │ │ │ ├── MetaDataToFolderStruct.ts # Folder organization
│ │ │ │ ├── RenamingRule.ts # Virtual path rules
│ │ │ │ ├── defaults/ # Default renaming rules
│ │ │ │ ├── template/ # TemplateEngine, ConditionEvaluator
│ │ │ │ └── types/ # RenamingRuleTypes.ts
│ │ │ ├── webdav/TokenStore.ts # Per-device WebDAV tokens
│ │ │ └── index.ts # Entry point
│ │ ├── package.json
│ │ └── tsconfig.json
│ │
│ ├── meta-fuse-driver/ # Rust FUSE driver (fuser)
│ │ ├── src/
│ │ │ ├── main.rs # Entry point, FUSE ops, inode mapping
│ │ │ └── api_client.rs # HTTP client to API server
│ │ ├── Cargo.toml
│ │ └── Cargo.lock
│ │
│ └── meta-fuse-ui/ # Dashboard (Vite + React): stats, rules editor, WebDAV tokens
│
├── docs/ # Architecture documentation
├── docker/
│ ├── nginx.conf # Reverse proxy config
│ ├── wsgidav.yaml # WebDAV server config
│ ├── webdav_token_controller.py # WsgiDAV DomainController (token auth)
│ ├── supervisord.conf # Process management
│ ├── start-fuse-driver.sh # Waits for the API, then mounts
│ └── welcome.html
│
├── Dockerfile
├── docker-compose.yml # Legacy standalone example (see note below)
├── package.json # Workspace root
└── pnpm-workspace.yaml
Key Components (meta-fuse-core)
| Component | File | Purpose |
|---|---|---|
| Entry Point | src/index.ts |
Initializes KV manager, VFS, SSE consumer, API server |
| API Server | src/api/APIServer.ts |
Fastify REST API for FUSE operations, rules, tokens, neighbours |
| KV Manager | src/kv/KVManager.ts |
Never owns storage: locates meta-core, builds the client, reconnects |
| Leader Client | src/kv/LeaderClient.ts |
Locates meta-core over UDP (name is legacy: no election involved) |
| meta-core API Client | src/kv/MetaCoreApiClient.ts |
/meta/{hash}/{prop}, /meta/{hash}, /meta reads |
| SSE Event Client | src/kv/SSEEventClient.ts |
Consumes /api/events/meta (replays from 0-0 every start) |
| Virtual FS | src/vfs/VirtualFileSystem.ts |
In-memory VFS representation with caching |
| Streaming State Builder | src/vfs/StreamingStateBuilder.ts |
Turns meta:events into VFS state incrementally |
| Rules Property Extractor | src/vfs/RulesPropertyExtractor.ts |
Extracts VFS-relevant properties from renaming rules |
| Folder Organizer | src/vfs/MetaDataToFolderStruct.ts |
Converts flat metadata to organized folder structure |
| Template Engine | src/vfs/template/TemplateEngine.ts |
Variable interpolation for renaming templates |
| Condition Evaluator | src/vfs/template/ConditionEvaluator.ts |
Evaluates rule conditions against file metadata |
| Token Store | src/webdav/TokenStore.ts |
Mints/lists/revokes WebDAV tokens |
Configuration
Environment Variables
# meta-core location
META_CORE_URL= # Pin meta-core's API URL; UDP discovery never overrides it
ENABLE_UDP_DISCOVERY=true # false/0 disables meta-discovery
ALLOW_LEGACY_REDIS_URL= # 1 = warn instead of fail if meta-core publishes redisUrl
# Announce / nav menu
BASE_URL= # External (Caddy) URL
PUBLIC_URL= # Wins over BASE_URL (debug-direct port, no Caddy)
# Paths
FILES_VOLUME=/files # Prefix for the relative filePath of each record
CONFIG_DIR=/meta-fuse/config # renaming-rules.json, webdav-tokens.json
# API Server
API_PORT=3000 # API server port
API_HOST=0.0.0.0 # API bind address
# VFS attributes (core)
FUSE_FILE_MODE=644 # File permissions (octal)
FUSE_DIR_MODE=755 # Directory permissions (octal)
PUID=1000 # File owner uid (core + driver)
PGID=1000 # File owner gid (core + driver)
# FUSE driver (args: <mountpoint> [api-url] [uid] [gid])
FUSE_API_URL=http://localhost:3000 # Used when api-url arg is omitted
FUSE_FILE_PERM / FUSE_DIR_PERM # Driver-side permission overrides
# Mount always uses allow_other (needs user_allow_other in /etc/fuse.conf)
# WsgiDAV
TOKEN_STORE_PATH=/meta-fuse/config/webdav-tokens.json
Docker Compose
The CasaOS store app (packages/MetaAppStore/Apps/MetaFuse/docker-compose.yml) is the reference deployment. Trimmed:
services:
metafuse-app:
image: ghcr.io/worph/meta-fuse:<version>
privileged: true # Required for FUSE
cap_add: [SYS_ADMIN, DAC_READ_SEARCH, DAC_OVERRIDE]
devices:
- /dev/fuse:/dev/fuse
security_opt:
- apparmor:unconfined
expose:
- 80 # nginx (UI, API, WebDAV)
volumes:
# No /meta-core mount (UDP discovery), no /files mount (WebDAV via meta-core)
- ${DATA_ROOT:-/DATA}/MetaFuse/Library:/mnt/virtual:shared # FUSE mount output
- ${DATA_ROOT:-/DATA}/AppData/metafuse/config:/meta-fuse/config:rw
environment:
- CONFIG_DIR=/meta-fuse/config
- BASE_URL=https://metafuse-$APP_DOMAIN
networks: [pcs] # must share a multicast-capable network with meta-core
The repo-root docker-compose.yml predates meta-core (it sets REDIS_URL and mounts /data) and is not representative.
API Endpoints
FUSE API (Port 3000, proxied by nginx under /api/ and /health)
| Method | Endpoint | Description |
|---|---|---|
| Health & Status | ||
| GET | /health |
Health check |
| GET | /api/health |
Health check (alias) |
| GET | /api/fuse/health |
Health check (alias) |
| GET | /api/fuse/stats |
Filesystem statistics |
| FUSE Operations | ||
| POST | /api/fuse/readdir |
List directory contents |
| POST | /api/fuse/getattr |
Get file/directory attributes |
| POST | /api/fuse/exists |
Check path existence |
| POST | /api/fuse/read |
Resolve file content (source path / WebDAV URL) |
| POST | /api/fuse/metadata |
Get full metadata for a path |
| GET | /api/fuse/files |
List all virtual files |
| GET | /api/fuse/directories |
List all virtual directories |
| POST | /api/fuse/refresh |
Trigger VFS refresh (replays the event stream) |
| Renaming Rules | ||
| GET | /api/fuse/rules |
Get current renaming rules configuration |
| PUT | /api/fuse/rules |
Update renaming rules configuration |
| POST | /api/fuse/rules/preview |
Preview how files would be renamed |
| POST | /api/fuse/rules/validate |
Validate a single rule |
| GET | /api/fuse/rules/variables |
Get list of available template variables |
| WebDAV Tokens | ||
| GET | /api/webdav-tokens |
List tokens (hashes/prefixes only) |
| POST | /api/webdav-tokens |
Create a token ({ "label": "..." }); plaintext returned once |
| DELETE | /api/webdav-tokens/:id |
Revoke a token |
| Service Discovery | ||
| GET | /api/neighbors |
Services heard over beacon v2 (nav menu) |
Example Responses
GET /api/fuse/stats
{
"fileCount": 1523,
"directoryCount": 48,
"totalSize": 1847392847362,
"lastRefresh": "2026-01-15T10:30:00.000Z",
"redisConnected": true
}
POST /api/fuse/readdir
// Request
{ "path": "/Movies" }
// Response
{
"entries": ["Action", "Comedy", "Drama", "Sci-Fi"]
}
POST /api/fuse/getattr
// Request
{ "path": "/Movies/Action/Movie.mkv" }
// Response (mode includes the file-type bits; times are epoch seconds)
{
"size": 4831838208,
"mode": 33188,
"mtime": 1705314600,
"atime": 1705314600,
"ctime": 1705314600,
"nlink": 1,
"uid": 1000,
"gid": 1000
}
Usage
Docker
# Build the image (bundles UI, backend, FUSE driver, WsgiDAV, nginx)
docker build -t meta-fuse .
# Check health (through nginx on port 80)
curl http://localhost/health
Images are published to ghcr.io/worph/meta-fuse by .github/workflows/docker-publish.yml. In the meta-root dev stack the service is metafuse-app (https://metafuse-dev.localhost:8181 via Caddy, debug-direct http://localhost:18181); rebuild it with dev/scripts/reload-meta-fuse.sh.
Mount WebDAV
Create a token in the dashboard (WebDAV tokens panel) first; use it as the password. The username can be anything non-empty.
# Windows
net use Z: https://<metafuse host>/webdav /user:me mfwd_xxxxxxxx
dir Z:\Movies
# Linux (davfs2)
sudo apt-get install davfs2
mkdir -p ~/meta-fuse
sudo mount -t davfs https://<metafuse host>/webdav ~/meta-fuse
# Credentials: any username / your mfwd_ token
ls ~/meta-fuse/Movies
# macOS: Finder → Go → Connect to Server → https://<metafuse host>/webdav
Development
Prerequisites
- Node.js 21.6.2+
- pnpm
- Rust 1.89+ (for FUSE driver; the Dockerfile builds with
rust:1.89-bookworm) - Docker & Docker Compose
Local Development
pnpm install
pnpm run build # all packages
pnpm run dev # tsc --watch (core) + vite (ui), in parallel
pnpm run test # @meta-fuse/core (mocha)
pnpm run lint
Inside the meta-root, prefer the dev stack's in-container build (dev/scripts/reload-meta-fuse.sh) — see the meta-root CLAUDE.md.
Building FUSE Driver
cd packages/meta-fuse-driver
cargo build --release --locked
# Run driver: <mountpoint> [api-url] [uid] [gid]
./target/release/meta-fuse-driver /mnt/virtual http://localhost:3000
Project Scripts
| Command | Description |
|---|---|
pnpm run build |
Build all packages |
pnpm run dev |
Development mode with hot reload |
pnpm run start / start:core |
Start core service |
pnpm run start:ui |
Start UI dev server |
pnpm run test |
Run core tests |
pnpm run lint |
Lint all packages |
How It Works
Virtual Filesystem Flow
1. Client opens /mnt/virtual/Movies/Action/Movie.mkv
│
▼
2. FUSE driver receives the request
- Converts path to inode
- Calls API: POST /api/fuse/getattr, then /api/fuse/read
│
▼
3. API server resolves the path from its in-memory VFS
- Returns a webdavUrl on meta-core's WebDAV for the source file
│
▼
4. FUSE driver reads byte ranges from that URL (HTTP Range)
│
▼
5. Content streamed to client
- No file duplication
- Bytes come from the original location via meta-core
Metadata Access
meta-fuse never talks to Redis. It reads records through meta-core's HTTP API:
GET /meta → { hashIds: [...] } enumerate records
GET /meta/{hash} → { metadata: {...} } full flat record
GET /meta/{hash}/{prop} → text/plain value one property (e.g. titles/eng)
# VFS paths are computed from metadata by the renaming rules, e.g.
# /Movies/Inception (2010)/Inception.mkv
# → filePath "media1/Movies/Inception (2010)/Inception.mkv" (relative to FILES_VOLUME)
Field names and value formats: meta-root METADATA_KEYS.md. File paths are relative to FILES_VOLUME (/files).
Real-Time Updates via SSE
meta-fuse consumes meta-core's meta:events stream through SSE at GET {apiUrl}/api/events/meta. Each event is a property change:
// SSE event → StreamMessage
{
id: string; // Stream entry ID (e.g., "1703808000000-0")
type: 'set' | 'del'; // SSE event name
key: string; // e.g. "file:abc123/title"
}
Startup Sequence:
- Bootstrap: VFS state is held only in memory, so every start replays from cursor
0-0(the cursor is deliberately not persisted; agapevent resumes from the oldest retained entry) - Build State: Parse
file:{hashId}/{property}, skip properties the rules don't use, fetch the rest - Go Live: Keep consuming new events; a file appears in the VFS once it has a
filePath
Troubleshooting
FUSE Mount Not Working
ls -la /dev/fuse # FUSE available?
mount | grep virtual # mounted?
curl http://localhost/api/fuse/health
# Driver logs (inside the container)
tail -f /var/log/supervisor/fuse-driver.log /var/log/supervisor/fuse-driver_error.log
meta-core Not Found
# Who this service hears over UDP
curl http://localhost/api/neighbors
# meta-core's own view + URLs
curl -k https://metacore-dev.localhost:8083/api/neighbors
curl -k https://metacore-dev.localhost:8083/api/urls
# meta-fuse logs
docker logs metafuse-app | grep -E "LeaderClient|KVManager|SSE"
If multicast can't cross your network, pin it with META_CORE_URL.
WebDAV Not Accessible
curl -u me:mfwd_xxxxxxxx http://localhost/webdav/ # 401 = bad/revoked token
docker exec metafuse-app tail /var/log/supervisor/wsgidav_error.log
Files Not Appearing
curl http://localhost/api/fuse/stats
docker logs metafuse-app | grep "State builder"
curl -k https://metacore-dev.localhost:8083/api/stats # does meta-core have records?
Technology Stack
| Component | Technology | Purpose |
|---|---|---|
| Core Service | Node.js + TypeScript | API server, VFS logic |
| HTTP Framework | Fastify 5.x | REST API |
| FUSE Driver | Rust + fuser | Filesystem interface |
| WebDAV | WsgiDAV (Python) + token DomainController | Network file sharing |
| Metadata | meta-core HTTP API + SSE | Reads and live updates |
| Discovery | beacon v2 (UDP multicast) | Locating meta-core and neighbours |
| Reverse Proxy | nginx | Request routing |
| Containerization | Docker + supervisord | Deployment |
Integration with MetaMesh
- meta-core: Source of metadata (HTTP/SSE) and file bytes (WebDAV)
- meta-sort: Produces the metadata meta-fuse organizes
- meta-stremio: Reads the same metadata for streaming
# Is meta-sort producing records?
curl -k https://metasort-dev.localhost:8180/api/processing/status
curl -k https://metacore-dev.localhost:8083/api/stats
Documentation
- VFS Rebuild Architecture - How VFS state is built from the event stream
- Streaming Architecture - Event processing pipeline details
- API Reference - REST API documentation
(These predate the HTTP/SSE migration in places; the code is authoritative.)
License
MIT (see package.json).