Files

149 lines
4.3 KiB
Python
Raw Permalink Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
from __future__ import annotations
import json
import time
import urllib.error
import urllib.request
from collections.abc import Iterator
from dataclasses import dataclass
from typing import Any
from .stream import OpenAIStreamAccumulator
class OpenAITransportError(RuntimeError):
pass
class OpenAIHTTPError(OpenAITransportError):
def __init__(self, code: int, detail: str = "") -> None:
super().__init__(f"HTTP {code}")
self.code = code
self.detail = detail
def describe(self, label: str) -> str:
suffix = f"{self.detail[:300]}" if self.detail else ""
return f"{label}HTTP {self.code}{suffix}"
class OpenAIEmptyResponseError(OpenAITransportError):
pass
@dataclass(frozen=True)
class OpenAIChatCompletion:
content: Any
latency_ms: int
def chat_completion(
*,
api_key: str,
base_url: str,
model: str,
messages: list[dict[str, Any]],
timeout: int,
user_agent: str,
) -> OpenAIChatCompletion:
request = _request(api_key, base_url, model, messages, user_agent, stream=False)
started = time.perf_counter()
try:
with urllib.request.urlopen(request, timeout=timeout) as response:
result = json.loads(response.read().decode("utf-8"))
content = result["choices"][0]["message"]["content"]
except urllib.error.HTTPError as exc:
raise OpenAIHTTPError(exc.code, _http_error_detail(exc)) from exc
except (
urllib.error.URLError,
TimeoutError,
json.JSONDecodeError,
KeyError,
IndexError,
) as exc:
raise OpenAITransportError(str(exc)) from exc
return OpenAIChatCompletion(
content=content,
latency_ms=round((time.perf_counter() - started) * 1000),
)
def stream_chat_completion(
*,
api_key: str,
base_url: str,
model: str,
messages: list[dict[str, Any]],
timeout: int,
user_agent: str,
) -> Iterator[str]:
request = _request(api_key, base_url, model, messages, user_agent, stream=True)
yielded = False
try:
with urllib.request.urlopen(request, timeout=timeout) as response:
accumulator = OpenAIStreamAccumulator()
for raw_line in response:
line = raw_line.decode("utf-8", errors="replace").strip()
if not line or line.startswith(":"):
continue
if line.startswith("data:"):
line = line[5:].strip()
if line == "[DONE]":
break
try:
result = json.loads(line)
except json.JSONDecodeError:
continue
choices = result.get("choices") or []
if not choices:
continue
content = accumulator.feed(choices[0] or {})
if content:
yielded = True
yield str(content)
except urllib.error.HTTPError as exc:
raise OpenAIHTTPError(exc.code, _http_error_detail(exc)) from exc
except (urllib.error.URLError, TimeoutError, OSError) as exc:
raise OpenAITransportError(str(exc)) from exc
if not yielded:
raise OpenAIEmptyResponseError("empty response")
def _request(
api_key: str,
base_url: str,
model: str,
messages: list[dict[str, Any]],
user_agent: str,
*,
stream: bool,
) -> urllib.request.Request:
headers = {
"Content-Type": "application/json",
"Authorization": f"Bearer {api_key}",
"User-Agent": user_agent,
}
if stream:
headers["Accept"] = "text/event-stream"
return urllib.request.Request(
f"{base_url.rstrip('/')}/chat/completions",
data=json.dumps(
{"model": model, "messages": messages, "stream": stream},
ensure_ascii=False,
).encode("utf-8"),
headers=headers,
method="POST",
)
def _http_error_detail(exc: urllib.error.HTTPError) -> str:
try:
payload = json.loads(exc.read().decode("utf-8", errors="replace"))
error = payload.get("error")
if isinstance(error, dict):
return str(error.get("message") or error.get("code") or "")
if error:
return str(error)
return str(payload.get("message") or "")
except (json.JSONDecodeError, OSError):
return ""