feat: add node startup flow

packages/node/meshnet_node/cli.py

@@ -2,6 +2,7 @@
 
 import argparse
 import sys
+import time
 
 
 def main() -> None:
@@ -12,20 +13,34 @@ def main() -> None:
     subparsers = parser.add_subparsers(dest="command")
 
     start_cmd = subparsers.add_parser("start", help="Start the node server")
-    start_cmd.add_argument("--tracker", default="http://localhost:8080", help="Tracker URL")
+    start_cmd.add_argument(
+        "--tracker", default="http://localhost:8080", help="Tracker URL"
+    )
     start_cmd.add_argument("--port", type=int, default=7000, help="Port to listen on")
+    start_cmd.add_argument(
+        "--model", default="stub-model", help="Model preset to request from tracker"
+    )
+    start_cmd.add_argument(
+        "--host", default="0.0.0.0", help="Interface to bind to"
+    )
+    start_cmd.add_argument(
+        "--advertise-host",
+        help="Reachable host/IP to advertise to the tracker (defaults to FQDN when binding 0.0.0.0)",
+    )
 
     args = parser.parse_args()
 
     if args.command == "start":
-        from meshnet_node.server import StubNodeServer
+        from meshnet_node.startup import run_startup
 
-        node = StubNodeServer(port=args.port)
-        port = node.start()
-        print(f"meshnet-node listening on port {port}")
-        print(f"Tracker URL: {args.tracker}")
+        node = run_startup(
+            tracker_url=args.tracker,
+            port=args.port,
+            model=args.model,
+            host=args.host,
+            advertise_host=args.advertise_host,
+        )
         try:
-            import time
             while True:
                 time.sleep(1)
         except KeyboardInterrupt:

packages/node/meshnet_node/downloader.py

@@ -0,0 +1,62 @@
+"""Shard downloader — fetches or stubs a model shard from HuggingFace Hub.
+
+Cache layout: ~/.cache/meshnet/shards/<model>/layers_<start>-<end>/
+
+For "stub-model" (no HF repo), a placeholder JSON file is written so the
+test suite never touches the network.
+"""
+
+import json
+from pathlib import Path
+
+_DEFAULT_CACHE = Path.home() / ".cache" / "meshnet" / "shards"
+
+
+def download_shard(
+    model: str,
+    shard_start: int,
+    shard_end: int,
+    cache_dir: Path = _DEFAULT_CACHE,
+    hf_repo: str | None = None,
+    progress: bool = True,
+) -> Path:
+    """Ensure the shard is present in *cache_dir* and return its local path.
+
+    When *hf_repo* is None (or *model* is ``"stub-model"``), a placeholder
+    weights file is created locally — no network access required.  This keeps
+    the test suite hermetic while the real download path is exercised by
+    passing a non-stub *hf_repo*.
+    """
+    shard_dir = cache_dir / model / f"layers_{shard_start}-{shard_end}"
+    shard_dir.mkdir(parents=True, exist_ok=True)
+
+    if hf_repo is None or model == "stub-model":
+        stub_file = shard_dir / "weights.json"
+        if not stub_file.exists():
+            stub_file.write_text(json.dumps({
+                "model": model,
+                "shard_start": shard_start,
+                "shard_end": shard_end,
+                "stub": True,
+            }))
+            if progress:
+                print(f"  [stub] shard placeholder written to {stub_file}", flush=True)
+        else:
+            if progress:
+                print(f"  [stub] shard already cached at {shard_dir}", flush=True)
+        return shard_dir
+
+    from huggingface_hub import snapshot_download  # type: ignore[import]
+
+    if progress:
+        print(
+            f"  Downloading layers {shard_start}-{shard_end} from {hf_repo} ...",
+            flush=True,
+        )
+
+    local_dir = snapshot_download(
+        repo_id=hf_repo,
+        cache_dir=str(cache_dir),
+        local_dir=str(shard_dir),
+    )
+    return Path(local_dir)

packages/node/meshnet_node/hardware.py

@@ -0,0 +1,33 @@
+"""GPU hardware detection with graceful CPU fallback."""
+
+import subprocess
+
+
+def detect_hardware() -> dict:
+    """Detect GPU model and available VRAM. Returns hardware profile dict."""
+    try:
+        import torch  # type: ignore[import]
+        if torch.cuda.is_available():
+            idx = torch.cuda.current_device()
+            name = torch.cuda.get_device_name(idx)
+            props = torch.cuda.get_device_properties(idx)
+            vram_mb = props.total_memory // (1024 * 1024)
+            return {"device": "cuda", "gpu_name": name, "vram_mb": vram_mb}
+    except ImportError:
+        pass
+
+    try:
+        result = subprocess.run(
+            ["nvidia-smi", "--query-gpu=name,memory.total", "--format=csv,noheader,nounits"],
+            capture_output=True, text=True, timeout=5,
+        )
+        if result.returncode == 0 and result.stdout.strip():
+            line = result.stdout.strip().splitlines()[0]
+            parts = line.split(",", 1)
+            gpu_name = parts[0].strip()
+            vram_mb = int(parts[1].strip()) if len(parts) > 1 else 0
+            return {"device": "cuda", "gpu_name": gpu_name, "vram_mb": vram_mb}
+    except (FileNotFoundError, subprocess.TimeoutExpired, ValueError, IndexError):
+        pass
+
+    return {"device": "cpu", "gpu_name": None, "vram_mb": 0}

packages/node/meshnet_node/startup.py

@@ -0,0 +1,154 @@
+"""Full node startup sequence — self-configuring, non-interactive."""
+
+from __future__ import annotations
+
+import json
+import socket
+import sys
+import urllib.error
+import urllib.parse
+import urllib.request
+from pathlib import Path
+
+from .downloader import download_shard
+from .hardware import detect_hardware
+from .server import StubNodeServer
+from .wallet import load_or_create_wallet
+
+
+def _post_json(url: str, payload: dict, timeout: float = 10.0) -> dict:
+    data = json.dumps(payload).encode()
+    req = urllib.request.Request(
+        url, data=data, headers={"Content-Type": "application/json"}, method="POST"
+    )
+    with urllib.request.urlopen(req, timeout=timeout) as r:
+        return json.loads(r.read())
+
+
+def _get_json(url: str, timeout: float = 10.0) -> dict:
+    with urllib.request.urlopen(url, timeout=timeout) as r:
+        return json.loads(r.read())
+
+
+def run_startup(
+    tracker_url: str,
+    port: int = 0,
+    model: str = "stub-model",
+    wallet_path: Path | None = None,
+    cache_dir: Path | None = None,
+    host: str = "127.0.0.1",
+    advertise_host: str | None = None,
+) -> StubNodeServer:
+    """Execute the full startup sequence and return a running node server.
+
+    Steps (all non-interactive):
+      1. Detect GPU / hardware profile
+      2. Load or generate Solana wallet keypair
+      3. Query tracker for optimal shard assignment
+      4. Download (or stub) the assigned shard
+      5. Start local HTTP server
+      6. Register with tracker
+
+    Prints a compact status summary on completion.
+    """
+
+    tracker_url = tracker_url.rstrip("/")
+
+    # 1. Hardware detection
+    print("Detecting hardware...", flush=True)
+    hw = detect_hardware()
+    device: str = hw["device"]
+    gpu_name: str | None = hw.get("gpu_name")
+    vram_mb: int = hw.get("vram_mb", 0)
+
+    if device == "cpu":
+        print("  WARNING: No CUDA GPU detected — running in CPU mode", flush=True)
+    else:
+        print(f"  GPU: {gpu_name} ({vram_mb} MB VRAM)", flush=True)
+
+    # 2. Wallet
+    print("Loading wallet...", flush=True)
+    wallet_kwargs: dict = {}
+    if wallet_path is not None:
+        wallet_kwargs["path"] = wallet_path
+    _, _, address = load_or_create_wallet(**wallet_kwargs)
+    print(f"  Wallet: {address}", flush=True)
+
+    # 3. Shard assignment from tracker
+    print("Querying tracker for shard assignment...", flush=True)
+    assign_qs = urllib.parse.urlencode({
+        "model": model,
+        "device": device,
+        "vram_mb": vram_mb,
+    })
+    try:
+        assignment = _get_json(f"{tracker_url}/v1/nodes/assign?{assign_qs}")
+    except urllib.error.URLError as exc:
+        print(f"  ERROR: Cannot reach tracker at {tracker_url}: {exc}", file=sys.stderr, flush=True)
+        raise
+
+    shard_start: int = assignment["shard_start"]
+    shard_end: int = assignment["shard_end"]
+    assigned_model: str = assignment.get("model", model)
+    hf_repo: str | None = assignment.get("hf_repo")
+    print(f"  Shard: layers {shard_start}-{shard_end} of {assigned_model}", flush=True)
+
+    # 4. Download shard
+    print("Downloading shard...", flush=True)
+    dl_kwargs: dict = {}
+    if cache_dir is not None:
+        dl_kwargs["cache_dir"] = cache_dir
+    if hf_repo is not None:
+        dl_kwargs["hf_repo"] = hf_repo
+    shard_path = download_shard(assigned_model, shard_start, shard_end, **dl_kwargs)
+    print(f"  Cached at: {shard_path}", flush=True)
+
+    # 5. Start HTTP server
+    is_last = shard_end >= assignment.get("model_layers_end", shard_end)
+    node = StubNodeServer(
+        host=host,
+        port=port,
+        shard_start=shard_start,
+        shard_end=shard_end,
+        is_last_shard=is_last,
+    )
+    actual_port = node.start()
+    public_host = advertise_host or (socket.getfqdn() if host == "0.0.0.0" else host)
+    endpoint = f"http://{public_host}:{actual_port}"
+
+    # 6. Register with tracker
+    print("Registering with tracker...", flush=True)
+    try:
+        reg_resp = _post_json(
+            f"{tracker_url}/v1/nodes/register",
+            {
+                "endpoint": endpoint,
+                "shard_start": shard_start,
+                "shard_end": shard_end,
+                "hardware_profile": hw,
+                "wallet_address": address,
+                "score": 1.0,
+            },
+        )
+        node_id: str = reg_resp["node_id"]
+    except Exception:
+        node.stop()
+        raise
+
+    # Status summary
+    hw_str = device.upper()
+    if gpu_name:
+        hw_str += f" ({gpu_name}, {vram_mb} MB)"
+    print(
+        f"\n{'=' * 32}\n"
+        f"meshnet-node ready\n"
+        f"  Wallet:   {address}\n"
+        f"  Shard:    layers {shard_start}-{shard_end} ({assigned_model})\n"
+        f"  Endpoint: {endpoint}\n"
+        f"  Node ID:  {node_id}\n"
+        f"  Hardware: {hw_str}\n"
+        f"{'=' * 32}",
+        flush=True,
+    )
+
+    return node

packages/node/meshnet_node/wallet.py

@@ -0,0 +1,64 @@
+"""Solana wallet management — load or generate an Ed25519 keypair.
+
+Solana keypair format: 64-byte array stored as JSON list of ints.
+  bytes 0-31: private scalar (seed)
+  bytes 32-63: public key (on-curve point)
+Wallet address: base58-encoded 32-byte public key.
+"""
+
+import json
+from pathlib import Path
+
+_DEFAULT_WALLET_PATH = Path.home() / ".config" / "meshnet" / "wallet.json"
+
+_B58_ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
+
+
+def _b58encode(data: bytes) -> str:
+    n = int.from_bytes(data, "big")
+    chars: list[str] = []
+    while n:
+        n, rem = divmod(n, 58)
+        chars.append(_B58_ALPHABET[rem])
+    leading = 0
+    for b in data:
+        if b == 0:
+            leading += 1
+        else:
+            break
+    return "1" * leading + "".join(reversed(chars))
+
+
+def load_or_create_wallet(
+    path: Path = _DEFAULT_WALLET_PATH,
+) -> tuple[bytes, bytes, str]:
+    """Return (secret_32, public_32, address_base58).
+
+    Loads from *path* if it exists; otherwise generates a new keypair and
+    saves it.  The parent directory is created if needed.
+    """
+    if path.exists():
+        mode = path.stat().st_mode & 0o777
+        if mode & 0o077:
+            path.chmod(0o600)
+        raw = bytes(json.loads(path.read_text()))
+        if len(raw) != 64:
+            raise ValueError(f"Wallet at {path} has unexpected length {len(raw)}, expected 64")
+        secret, public = raw[:32], raw[32:]
+        return secret, public, _b58encode(public)
+
+    from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PrivateKey
+    from cryptography.hazmat.primitives.serialization import (
+        Encoding, NoEncryption, PrivateFormat, PublicFormat,
+    )
+
+    priv = Ed25519PrivateKey.generate()
+    secret = priv.private_bytes(Encoding.Raw, PrivateFormat.Raw, NoEncryption())
+    public = priv.public_key().public_bytes(Encoding.Raw, PublicFormat.Raw)
+    keypair = list(secret) + list(public)
+
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_text(json.dumps(keypair))
+    path.chmod(0o600)
+
+    return secret, public, _b58encode(public)

packages/node/pyproject.toml

@@ -8,6 +8,11 @@ version = "0.1.0"
 description = "Distributed Inference Network node client"
 requires-python = ">=3.10"
 
+dependencies = [
+    "cryptography>=41",
+    "huggingface-hub>=0.20",
+]
+
 [project.scripts]
 meshnet-node = "meshnet_node.cli:main"