exo/exo/orchestration/standard_node.py

import numpy as np
import json
import asyncio
import uuid
import time
import traceback
from typing import List, Dict, Optional, Tuple, Union
from exo.networking import Discovery, PeerHandle, Server
from exo.inference.inference_engine import InferenceEngine, Shard
from .node import Node
from exo.topology.topology import Topology
from exo.topology.device_capabilities import device_capabilities
from exo.topology.partitioning_strategy import Partition, PartitioningStrategy, map_partitions_to_shards
from exo import DEBUG
from exo.helpers import AsyncCallbackSystem
from exo.viz.topology_viz import TopologyViz
from exo.download.hf.hf_helpers import RepoProgressEvent


class StandardNode(Node):
  def __init__(
    self,
    _id: str,
    server: Server,
    inference_engine: InferenceEngine,
    discovery: Discovery,
    partitioning_strategy: PartitioningStrategy = None,
    max_generate_tokens: int = 1024,
    topology_viz: Optional[TopologyViz] = None,
  ):
    self.id = _id
    self.inference_engine = inference_engine
    self.server = server
    self.discovery = discovery
    self.partitioning_strategy = partitioning_strategy
    self.peers: List[PeerHandle] = {}
    self.topology: Topology = Topology()
    self.device_capabilities = device_capabilities()
    self.buffered_token_output: Dict[str, Tuple[List[int], bool]] = {}
    self.max_generate_tokens = max_generate_tokens
    self.topology_viz = topology_viz
    self._on_token = AsyncCallbackSystem[str, Tuple[str, List[int], bool]]()
    self._on_opaque_status = AsyncCallbackSystem[str, Tuple[str, str]]()
    self._on_opaque_status.register("node_status").on_next(self.on_node_status)
    self.node_download_progress: Dict[str, RepoProgressEvent] = {}

  async def start(self, wait_for_peers: int = 0) -> None:
    await self.server.start()
    await self.discovery.start()
    await self.update_peers(wait_for_peers)
    await self.collect_topology()
    if DEBUG >= 2: print(f"Collected topology: {self.topology}")
    asyncio.create_task(self.periodic_topology_collection(1.0))

  async def stop(self) -> None:
    await self.discovery.stop()
    await self.server.stop()

  def on_node_status(self, request_id, opaque_status):
    try:
      status_data = json.loads(opaque_status)
      if status_data.get("type", "") == "node_status":
        if status_data.get("status", "").startswith("start_"):
          self.current_topology.active_node_id = status_data.get("node_id")
        elif status_data.get("status", "").startswith("end_"):
          if status_data.get("node_id") == self.current_topology.active_node_id:
            self.current_topology.active_node_id = None
      download_progress = None
      if status_data.get("type", "") == "download_progress":
        if DEBUG >= 8: print(f"Download progress from {status_data.get('node_id')}: {status_data.get('progress')}")
        download_progress = RepoProgressEvent.from_dict(status_data.get('progress'))
        self.node_download_progress[status_data.get('node_id')] = download_progress
      if self.topology_viz:
        self.topology_viz.update_visualization(self.current_topology, self.partitioning_strategy.partition(self.current_topology), self.id, self.node_download_progress)
    except Exception as e:
      if DEBUG >= 1: print(f"Error updating visualization: {e}")
      if DEBUG >= 1: traceback.print_exc()

  def get_supported_inference_engines(self):
    supported_engines = []
    if self.inferenceEngine == 'mlx':
      supported_engines.extend('mlx', 'tinygrad')
    else:
      supported_engines.append('tinygrad')
    return supported_engines

  async def broadcast_supported_engines(self, supported_engines: List):
    await self.broadcast_opaque_status("", json.dumps({
      "type": "supported_inference_engines",
      "node_id": self.id, 
      "engines": supported_engines
    }))

  async def process_prompt(self, base_shard: Shard, prompt: str, image_str: Optional[str] = None, request_id: Optional[str] = None, inference_state: Optional[str] = None) -> Optional[np.ndarray]:
    shard = self.get_current_shard(base_shard)
    asyncio.create_task(
      self.broadcast_opaque_status(
        request_id,
        json.dumps({
          "type": "node_status",
          "node_id": self.id,
          "status": "start_process_prompt",
          "base_shard": base_shard.to_dict(),
          "shard": shard.to_dict(),
          "prompt": prompt,
          "image_str": image_str,
          "inference_state": inference_state,
          "request_id": request_id,
        }),
      )
    )
    start_time = time.perf_counter_ns()
    resp = await self._process_prompt(base_shard, prompt, image_str, request_id, inference_state)
    end_time = time.perf_counter_ns()
    elapsed_time_ns = end_time - start_time
    asyncio.create_task(
      self.broadcast_opaque_status(
        request_id,
        json.dumps({
          "type": "node_status",
          "node_id": self.id,
          "status": "end_process_prompt",
          "base_shard": base_shard.to_dict(),
          "shard": shard.to_dict(),
          "prompt": prompt,
          "image_str": image_str,
          "inference_state": inference_state,
          "request_id": request_id,
          "elapsed_time_ns": elapsed_time_ns,
          "result_size": resp.size if resp is not None else 0,
        }),
      )
    )
    return resp

  async def _process_prompt(self, base_shard: Shard, prompt: str, image_str: Optional[str] = None, request_id: Optional[str] = None, inference_state: Optional[str] = None) -> Optional[np.ndarray]:
    if request_id is None:
      request_id = str(uuid.uuid4())
    if request_id not in self.buffered_token_output:
      self.buffered_token_output[request_id] = ([], False)
    shard = self.get_current_shard(base_shard)

    if DEBUG >= 2: print(f"[{request_id}] process prompt: {base_shard=} {shard=} {prompt=} {image_str=}")
    if shard.start_layer != 0:
      if DEBUG >= 2: print(f"[{request_id}] forwarding to next shard: {base_shard=} {shard=} {prompt=} {image_str=}")
      await self.forward_to_next_shard(shard, prompt, request_id, image_str=image_str, inference_state=inference_state)
      return

    result, inference_state, is_finished = await self.inference_engine.infer_prompt(request_id, shard, prompt, image_str, inference_state=inference_state)
    is_finished = is_finished or len(self.buffered_token_output[request_id][0]) >= self.max_generate_tokens
    if is_finished:
      self.buffered_token_output[request_id] = (self.buffered_token_output[request_id][0], True)
    asyncio.create_task(self.broadcast_result(request_id, self.buffered_token_output[request_id][0], is_finished))  # TODO: this is n^2 communication complexity

    if result.size == 1:
      self.buffered_token_output[request_id][0].append(result.item())
      self.trigger_on_token_callbacks(request_id, self.buffered_token_output[request_id][0], is_finished)

    if DEBUG >= 2: print(f"[{request_id}] result size: {result.size}, is finished: {is_finished}, buffered tokens: {len(self.buffered_token_output[request_id][0])}")

    if not is_finished:
      asyncio.create_task(self.forward_to_next_shard(shard, result, request_id, image_str=image_str, inference_state=inference_state))

    return np.array(self.buffered_token_output[request_id][0]) if len(self.buffered_token_output[request_id][0]) > 0 else None

  async def process_tensor(
    self,
    base_shard: Shard,
    tensor: np.ndarray,
    request_id: Optional[str] = None,
    inference_state: Optional[str] = None,
  ) -> Optional[np.ndarray]:
    shard = self.get_current_shard(base_shard)
    asyncio.create_task(
      self.broadcast_opaque_status(
        request_id,
        json.dumps({
          "type": "node_status",
          "node_id": self.id,
          "status": "start_process_tensor",
          "base_shard": base_shard.to_dict(),
          "shard": shard.to_dict(),
          "tensor_size": tensor.size,
          "tensor_shape": tensor.shape,
          "request_id": request_id,
          "inference_state": inference_state,
        }),
      )
    )
    start_time = time.perf_counter_ns()
    resp = await self._process_tensor(shard, tensor, request_id, inference_state)
    end_time = time.perf_counter_ns()
    elapsed_time_ns = end_time - start_time
    asyncio.create_task(
      self.broadcast_opaque_status(
        request_id,
        json.dumps({
          "type": "node_status",
          "node_id": self.id,
          "status": "end_process_tensor",
          "base_shard": base_shard.to_dict(),
          "shard": shard.to_dict(),
          "request_id": request_id,
          "elapsed_time_ns": elapsed_time_ns,
          "result_size": resp.size if resp is not None else 0,
        }),
      )
    )
    return resp

  async def _process_tensor(
    self,
    base_shard: Shard,
    tensor: np.ndarray,
    request_id: Optional[str] = None,
    inference_state: Optional[str] = None,
  ) -> Optional[np.ndarray]:
    if request_id is None:
      request_id = str(uuid.uuid4())
    if request_id not in self.buffered_token_output:
      self.buffered_token_output[request_id] = ([], False)
    shard = self.get_current_shard(base_shard)

    try:
      if DEBUG >= 1: print(f"[{request_id}] process_tensor: {tensor.size=} {tensor.shape=}")
      result, inference_state, is_finished = await self.inference_engine.infer_tensor(request_id, shard, tensor, inference_state=inference_state)
      is_finished = is_finished or len(self.buffered_token_output[request_id][0]) >= self.max_generate_tokens
      if is_finished:
        self.buffered_token_output[request_id] = (self.buffered_token_output[request_id][0], True)
      asyncio.create_task(self.broadcast_result(request_id, self.buffered_token_output[request_id][0], is_finished))  # TODO: this is n^2 communication complexity

      if result.size == 1:  # we got a new token out
        self.buffered_token_output[request_id][0].append(result.item())
        self.trigger_on_token_callbacks(request_id, self.buffered_token_output[request_id][0], is_finished)
      if DEBUG >= 2: print(f"[{request_id}] result size: {result.size}, is finished: {is_finished}, buffered tokens: {len(self.buffered_token_output[request_id][0])}")

      if not is_finished:
        asyncio.create_task(self.forward_to_next_shard(shard, result, request_id, inference_state=inference_state))

      return np.array(self.buffered_token_output[request_id][0]) if len(self.buffered_token_output[request_id][0]) > 0 else None
    except Exception as e:
      print(f"Error processing tensor for shard {shard}: {e}")
      traceback.print_exc()
      return None

  async def forward_to_next_shard(
    self,
    base_shard: Shard,
    tensor_or_prompt: Union[np.ndarray, str],
    request_id: str,
    image_str: Optional[str] = None,
    inference_state: Optional[str] = None,
  ) -> None:
    if not self.partitioning_strategy:
      if DEBUG >= 1: print("No partitioning strategy found. Skipping forward.")
      return
    shard = self.get_current_shard(base_shard)

    partitions = self.partitioning_strategy.partition(self.topology)
    shards = map_partitions_to_shards(self.partitioning_strategy.partition(self.topology), base_shard.n_layers, base_shard.model_id)
    current_partition_index = next((i for i, p in enumerate(partitions) if p.node_id == self.id), None)
    if DEBUG >= 1: print(f"Current partition index: {current_partition_index}")
    if current_partition_index is not None:
      next_partition_index = (current_partition_index+1) % len(partitions)
      next_partition: Partition = partitions[next_partition_index]
      next_shard = shards[next_partition_index]
      if DEBUG >= 2: print(f"Computed next from: {shard}, {self.topology}. Next partition: {next_partition}")

      if next_partition.node_id == self.id:
        if isinstance(tensor_or_prompt, np.ndarray):
          await self.process_tensor(shard, tensor_or_prompt, request_id, inference_state=inference_state)
        else:
          await self.process_prompt(shard, tensor_or_prompt, image_str, request_id, inference_state=inference_state)
        return

      target_peer = next((p for p in self.peers if p.id() == next_partition.node_id), None)
      if not target_peer:
        raise ValueError(f"Peer for {next_partition} not found")

      if DEBUG >= 1: print(f"Sending tensor_or_prompt to {target_peer.id()}: {tensor_or_prompt}")

      if isinstance(tensor_or_prompt, np.ndarray):
        await target_peer.send_tensor(next_shard, tensor_or_prompt, request_id=request_id, inference_state=inference_state)
      else:
        await target_peer.send_prompt(next_shard, tensor_or_prompt, image_str=image_str, request_id=request_id, inference_state=inference_state)

  def get_current_shard(self, base_shard: Shard) -> Shard:
    partitions = self.partitioning_strategy.partition(self.topology)
    shards = map_partitions_to_shards(partitions, base_shard.n_layers, base_shard.model_id)
    current_partition_index = next((i for i, p in enumerate(partitions) if p.node_id == self.id), None)
    if current_partition_index is None:
      raise ValueError(f"No current partition found for node: {self.id}")
    return shards[current_partition_index]

  async def update_peers(self, wait_for_peers: int = 0) -> bool:
    next_peers = await self.discovery.discover_peers(wait_for_peers)
    current_peer_ids = {peer.id() for peer in self.peers}
    next_peer_ids = {peer.id() for peer in next_peers}
    peers_added = [peer for peer in next_peers if peer.id() not in current_peer_ids]
    peers_removed = [peer for peer in self.peers if peer.id() not in next_peer_ids]
    peers_updated = [
      peer for peer in next_peers
      if peer.id() in current_peer_ids and any(p.addr() != peer.addr() for p in self.peers if p.id() == peer.id())
    ]
    peers_unchanged = [
      peer for peer in next_peers
      if peer.id() in current_peer_ids and all(p.addr() == peer.addr() for p in self.peers if p.id() == peer.id())
    ]
    peers_to_disconnect = [peer for peer in peers_removed if await peer.is_connected()]
    peers_to_connect = [peer for peer in peers_added + peers_updated + peers_unchanged if not await peer.is_connected()]

    def _pretty(peers: List[PeerHandle]) -> List[str]:
      return [f"{peer.id()}@{peer.addr()}" for peer in peers]
    if DEBUG >= 2: print(f"update_peers: added={peers_added} removed={peers_removed} updated={peers_updated} unchanged={peers_unchanged} to_disconnect={peers_to_disconnect} to_connect={peers_to_connect}")

    async def disconnect_with_timeout(peer, timeout=5):
      try:
        await asyncio.wait_for(peer.disconnect(), timeout)
        return True
      except Exception as e:
        print(f"Error disconnecting peer {peer.id()}@{peer.addr()}: {e}")
        traceback.print_exc()
        return False

    async def connect_with_timeout(peer, timeout=5):
      try:
        await asyncio.wait_for(peer.connect(), timeout)
        return True
      except Exception as e:
        print(f"Error connecting peer {peer.id()}@{peer.addr()}: {e}")
        traceback.print_exc()
        return False

    disconnect_results = await asyncio.gather(
      *(disconnect_with_timeout(peer) for peer in peers_to_disconnect),
      return_exceptions=True
    )
    connect_results = await asyncio.gather(
      *(connect_with_timeout(peer) for peer in peers_to_connect),
      return_exceptions=True
    )

    successful_disconnects = [peer for peer, result in zip(peers_to_disconnect, disconnect_results) if result is True]
    failed_disconnects = [peer for peer, result in zip(peers_to_disconnect, disconnect_results) if result is False]
    successful_connects = [peer for peer, result in zip(peers_to_connect, connect_results) if result is True]
    failed_connects = [peer for peer, result in zip(peers_to_connect, connect_results) if result is False]
    if DEBUG >= 1:
      if successful_disconnects: print(f"Successfully disconnected peers: {_pretty(successful_disconnects)}")
      if failed_disconnects: print(f"Failed to disconnect peers: {_pretty(failed_disconnects)}")
      if successful_connects: print(f"Successfully connected peers: {_pretty(successful_connects)}")
      if failed_connects: print(f"Failed to connect peers: {_pretty(failed_connects)}")

    self.peers = next_peers
    return len(peers_added) > 0 or len(peers_removed) > 0 or len(peers_updated) > 0

  async def periodic_topology_collection(self, interval: int):
    while True:
      await asyncio.sleep(interval)
      try:
        did_peers_change = await self.update_peers()
        if DEBUG >= 2: print(f"{did_peers_change=}")
        if did_peers_change:
          await self.collect_topology()
      except Exception as e:
        print(f"Error collecting topology: {e}")
        traceback.print_exc()

  async def get_inference_result(self, request_id: str) -> Tuple[Optional[np.ndarray], bool]:
    if request_id not in self.buffered_token_output:
      return None, False
    return np.array(self.buffered_token_output[request_id][0]), self.buffered_token_output[request_id][1]

  async def collect_topology(self, visited: set[str] = set(), max_depth: int = 4) -> Topology:
    next_topology = Topology()
    next_topology.update_node(self.id, self.device_capabilities)

    if DEBUG >= 2: print(f"Collecting topology {max_depth=} {visited=}")

    prev_visited = visited.copy()
    visited.add(self.id)
    visited.update(p.id() for p in self.peers)

    for peer in self.peers:
      next_topology.update_node(peer.id(), peer.device_capabilities())
      next_topology.add_edge(self.id, peer.id())

      if peer.id() in prev_visited:
        continue

      if max_depth <= 0:
        if DEBUG >= 2: print("Max depth reached. Skipping...")
        continue

      try:
        other_topology = await asyncio.wait_for(peer.collect_topology(visited, max_depth=max_depth - 1), timeout=5.0)
        if DEBUG >= 2: print(f"Collected topology from: {peer.id()}: {other_topology}")
        self.topology.merge(other_topology)
      except Exception as e:
        print(f"Error collecting topology from {peer.id()}: {e}")

    next_topology.active_node_id = self.topology.active_node_id  # this is not so clean.
    self.topology = next_topology
    if self.topology_viz:
      self.topology_viz.update_visualization(self.current_topology, self.partitioning_strategy.partition(self.current_topology), self.id)
    return next_topology

  @property
  def on_token(self) -> AsyncCallbackSystem[str, Tuple[str, List[int], bool]]:
    return self._on_token

  @property
  def on_opaque_status(self) -> AsyncCallbackSystem[str, Tuple[str, str]]:
    return self._on_opaque_status

  def trigger_on_token_callbacks(self, request_id: str, tokens: List[int], is_finished: bool) -> None:
    if DEBUG >= 2: print(f"Triggering all on_token callbacks with {request_id=} num_tokens={len(tokens)} {is_finished=}")
    self.on_token.trigger_all(request_id, tokens, is_finished)

  async def broadcast_result(self, request_id: str, result: List[int], is_finished: bool) -> None:
    async def send_result_to_peer(peer):
      try:
        await asyncio.wait_for(peer.send_result(request_id, result, is_finished), timeout=15.0)
      except asyncio.TimeoutError:
        print(f"Timeout broadcasting result to {peer.id()}")
      except Exception as e:
        print(f"Error broadcasting result to {peer.id()}: {e}")
        traceback.print_exc()

    await asyncio.gather(*[send_result_to_peer(peer) for peer in self.peers], return_exceptions=True)

  async def broadcast_opaque_status(self, request_id: str, status: str) -> None:
    if DEBUG >= 8: print(f"Broadcasting opaque status: {request_id=} {status=}")

    async def send_status_to_peer(peer):
      try:
        await asyncio.wait_for(peer.send_opaque_status(request_id, status), timeout=15.0)
      except asyncio.TimeoutError:
        print(f"Timeout sending opaque status to {peer.id()}")
      except Exception as e:
        print(f"Error sending opaque status to {peer.id()}: {e}")
        traceback.print_exc()

    await asyncio.gather(*[send_status_to_peer(peer) for peer in self.peers], return_exceptions=True)
    # in the case of opaque status, we also want to receive our own opaque statuses
    self.on_opaque_status.trigger_all(request_id, status)

  @property
  def current_topology(self) -> Topology:
    return self.topology