import asyncio
import aiohttp
from aiohttp import web
import uuid
import pathlib
class OllamaServer:
def __init__(self, ws, models):
self.ws = ws
self.queues = {}
self.models = models
@property
def model_names(self):
return [model['name'] for model in self.models]
async def forward_to_http(self, request_id, message):
if request_id not in self.queues:
self.queues[request_id] = asyncio.Queue()
await self.queues[request_id].put(message)
async def forward_to_websocket(self, request_id, message, path):
self.queues[request_id] = asyncio.Queue()
await self.ws.send_json(dict(request_id=request_id, data=message, path=path))
while True:
chunk = await self.queues[request_id].get()
yield chunk
if chunk['done']:
break
async def serve(self):
async for msg in self.ws:
if msg.type == web.WSMsgType.TEXT:
data = msg.json()
request_id = data['request_id']
await self.forward_to_http(request_id, data['data'])
elif msg.type == web.WSMsgType.ERROR:
break
class NoServerFoundException(BaseException):
pass
class ServerManager:
def __init__(self):
self.servers = []
def add_server(self, server):
self.servers.append(server)
def remove_server(self, server):
self.servers.remove(server)
def get_server_by_model_name(self, model_name):
for server in self.servers:
if model_name in server.model_names:
return server
return None
async def forward_to_websocket(self, request_id, message, path):
try:
server = self.servers.pop(0)
self.servers.append(server)
server = self.get_server_by_model_name(message['model'])
if not server:
raise NoServerFoundException
async for msg in server.forward_to_websocket(request_id, message, path):
yield msg
except:
raise
def get_models(self):
models = {}
for server in self.servers:
for model_name in server.model_names:
if not model_name in models:
models[model_name] = 0
models[model_name] += 1
return models
server_manager = ServerManager()
async def websocket_handler(request):
ws = web.WebSocketResponse()
await ws.prepare(request)
models = await ws.receive_json()
server = OllamaServer(ws, models['models'])
server_manager.add_server(server)
async for msg in ws:
if msg.type == web.WSMsgType.TEXT:
data = msg.json()
await server.forward_to_http(data['request_id'], data['data'])
elif msg.type == web.WSMsgType.ERROR:
print(f'WebSocket connection closed with exception: {ws.exception()}')
server_manager.remove_server(server)
return ws
async def http_handler(request):
request_id = str(uuid.uuid4())
data = None
try:
data = await request.json()
except ValueError:
return web.Response(status=400)
resp = web.StreamResponse(headers={'Content-Type': 'application/x-ndjson', 'Transfer-Encoding': 'chunked'})
await resp.prepare(request)
import json
try:
async for result in server_manager.forward_to_websocket(request_id, data, path=request.path):
await resp.write(json.dumps(result).encode()+b'\r\n')
except NoServerFoundException:
await resp.write(json.dumps(dict(error="No server with that model found.",available=server_manager.get_models())).encode() + b'\r\n')
await resp.write_eof()
return resp
async def index_handler(request):
index_template = pathlib.Path("index.html").read_text()
client_py = pathlib.Path("client.py").read_text()
index_template = index_template.replace("#client.py", client_py)
return web.Response(text=index_template, content_type="text/html")
async def models_handler(self):
return web.json_response(server_manager.get_models())
app = web.Application()
app.router.add_get("/", index_handler)
app.router.add_route('GET', '/publish', websocket_handler)
app.router.add_route('POST', '/api/chat', http_handler)
app.router.add_route('POST', '/v1/api/chat', http_handler)
app.router.add_route('POST', '/v1/api/chat/completions', http_handler)
app.router.add_route('GET', '/models', models_handler)
if __name__ == '__main__':
web.run_app(app, port=1984)