Files
zk-data-agent/agent_platform/runtime/provider.py
T
2026-07-26 17:40:51 +08:00

250 lines
8.8 KiB
Python

from __future__ import annotations
import asyncio
from typing import Any
import httpx
from agent_platform.config import Settings
from agent_platform.models import Provider
TRANSIENT_COMPLETE_STATUS_CODES = frozenset({408, 425, 429, 500, 502, 503, 504, 524})
COMPLETE_MAX_ATTEMPTS = 2
COMPLETE_MAX_TOKENS = 4096
MAX_RETRY_DELAY_SECONDS = 5.0
def completions_url(base_url: str) -> str:
base = base_url.rstrip("/")
if base.endswith("/v1"):
return f"{base}/chat/completions"
return f"{base}/v1/chat/completions"
def retry_delay_seconds(response: httpx.Response | None, attempt: int) -> float:
if response is not None:
retry_after = response.headers.get("Retry-After")
if retry_after:
try:
return min(MAX_RETRY_DELAY_SECONDS, max(0.0, float(retry_after)))
except ValueError:
pass
return min(MAX_RETRY_DELAY_SECONDS, float(2 ** (attempt - 1)))
async def decode_complete_response(response: httpx.Response) -> dict[str, Any]:
content_type = response.headers.get("Content-Type", "").lower()
if "text/event-stream" not in content_type:
await response.aread()
data = response.json()
if not data.get("choices"):
raise RuntimeError("Model provider returned no choices")
return data
envelope: dict[str, Any] = {"object": "chat.completion"}
message: dict[str, Any] = {"role": "assistant", "content": None}
content_parts: list[str] = []
reasoning_parts: list[str] = []
tool_calls: dict[int, dict[str, Any]] = {}
finish_reason: str | None = None
usage: dict[str, Any] | None = None
saw_choice = False
async for line in response.aiter_lines():
if not line.startswith("data:"):
continue
raw = line[5:].strip()
if not raw or raw == "[DONE]":
continue
chunk = httpx.Response(200, content=raw).json()
if chunk.get("error"):
raise RuntimeError(f"Model provider stream error: {chunk['error']}")
for key in ("id", "created", "model", "system_fingerprint"):
if chunk.get(key) is not None:
envelope[key] = chunk[key]
if chunk.get("usage"):
usage = chunk["usage"]
choices = chunk.get("choices") or []
if not choices:
continue
saw_choice = True
choice = choices[0]
delta = choice.get("delta") or {}
if delta.get("role"):
message["role"] = delta["role"]
if isinstance(delta.get("content"), str):
content_parts.append(delta["content"])
reasoning = delta.get("reasoning_content")
if not isinstance(reasoning, str):
reasoning = delta.get("reasoning")
if isinstance(reasoning, str):
reasoning_parts.append(reasoning)
for position, fragment in enumerate(delta.get("tool_calls") or []):
index = int(fragment.get("index", position))
merged = tool_calls.setdefault(
index,
{
"id": "",
"type": "function",
"function": {"name": "", "arguments": ""},
},
)
if fragment.get("id"):
merged["id"] = fragment["id"]
if fragment.get("type"):
merged["type"] = fragment["type"]
function = fragment.get("function") or {}
if function.get("name"):
merged["function"]["name"] += function["name"]
if function.get("arguments"):
merged["function"]["arguments"] += function["arguments"]
if choice.get("finish_reason") is not None:
finish_reason = choice["finish_reason"]
if not saw_choice:
raise RuntimeError("Model provider stream returned no choices")
if content_parts:
message["content"] = "".join(content_parts)
if reasoning_parts:
message["reasoning_content"] = "".join(reasoning_parts)
if tool_calls:
message["tool_calls"] = [tool_calls[index] for index in sorted(tool_calls)]
envelope["choices"] = [
{
"index": 0,
"message": message,
"finish_reason": finish_reason,
}
]
if usage is not None:
envelope["usage"] = usage
return envelope
class ModelProvider:
def __init__(self, settings: Settings, client: httpx.AsyncClient | None = None) -> None:
self.settings = settings
self.client = client or httpx.AsyncClient(
timeout=httpx.Timeout(settings.model_timeout_seconds),
limits=httpx.Limits(max_connections=50, max_keepalive_connections=20),
)
self._owns_client = client is None
@property
def headers(self) -> dict[str, str]:
return self._headers("k1412")
def _headers(self, provider: Provider) -> dict[str, str]:
key = self.settings.deepseek_api_key if provider == "deepseek" else self.settings.model_api_key
return {
"Authorization": f"Bearer {key}",
"Content-Type": "application/json",
}
def _base_url(self, provider: Provider) -> str:
return self.settings.deepseek_api_base_url if provider == "deepseek" else self.settings.model_api_base_url
@staticmethod
def _provider_payload(
payload: dict[str, Any],
*,
provider: Provider,
thinking_enabled: bool,
reasoning_effort: str | None,
max_output_tokens: int,
) -> dict[str, Any]:
value = dict(payload)
value.pop("thinking", None)
value.pop("reasoning_effort", None)
value["max_tokens"] = max_output_tokens
if provider == "deepseek" and thinking_enabled:
value["thinking"] = {"type": "enabled"}
if reasoning_effort:
value["reasoning_effort"] = reasoning_effort
return value
async def close(self) -> None:
if self._owns_client:
await self.client.aclose()
async def complete(
self,
*,
model: str,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]] | None = None,
temperature: float | None = None,
provider: Provider = "k1412",
thinking_enabled: bool = False,
reasoning_effort: str | None = None,
max_output_tokens: int = COMPLETE_MAX_TOKENS,
) -> dict[str, Any]:
payload = self._provider_payload(
{
"model": model,
"messages": messages,
"stream": True,
},
provider=provider,
thinking_enabled=thinking_enabled,
reasoning_effort=reasoning_effort,
max_output_tokens=max_output_tokens,
)
if tools:
payload["tools"] = tools
payload["tool_choice"] = "auto"
if temperature is not None:
payload["temperature"] = temperature
for attempt in range(1, COMPLETE_MAX_ATTEMPTS + 1):
response: httpx.Response | None = None
try:
async with self.client.stream(
"POST",
completions_url(self._base_url(provider)),
headers=self._headers(provider),
json=payload,
) as response:
if response.status_code in TRANSIENT_COMPLETE_STATUS_CODES and attempt < COMPLETE_MAX_ATTEMPTS:
await response.aread()
await asyncio.sleep(retry_delay_seconds(response, attempt))
continue
response.raise_for_status()
return await decode_complete_response(response)
except httpx.TransportError:
if attempt >= COMPLETE_MAX_ATTEMPTS:
raise
await asyncio.sleep(retry_delay_seconds(response, attempt))
continue
raise RuntimeError("Model provider retry loop exited unexpectedly")
async def forward(
self,
payload: dict[str, Any],
*,
provider: Provider = "k1412",
thinking_enabled: bool = False,
reasoning_effort: str | None = None,
max_output_tokens: int = COMPLETE_MAX_TOKENS,
) -> httpx.Response:
payload = self._provider_payload(
payload,
provider=provider,
thinking_enabled=thinking_enabled,
reasoning_effort=reasoning_effort,
max_output_tokens=max_output_tokens,
)
request = self.client.build_request(
"POST",
completions_url(self._base_url(provider)),
headers=self._headers(provider),
json=payload,
)
response = await self.client.send(request, stream=bool(payload.get("stream")))
if response.status_code >= 400:
await response.aread()
response.raise_for_status()
return response