Merge pull request #481 from c0sogi/main

Added `RouteErrorHandler` for server
This commit is contained in:
Andrei 2023-07-20 17:41:42 -04:00 committed by GitHub
commit 365d9a4367
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2 changed files with 258 additions and 60 deletions

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@ -845,7 +845,7 @@ class Llama:
if len(prompt_tokens) >= llama_cpp.llama_n_ctx(self.ctx):
raise ValueError(
f"Requested tokens exceed context window of {llama_cpp.llama_n_ctx(self.ctx)}"
f"Requested tokens ({len(prompt_tokens)}) exceed context window of {llama_cpp.llama_n_ctx(self.ctx)}"
)
if max_tokens <= 0:

View file

@ -1,8 +1,9 @@
import json
import multiprocessing
from re import compile, Match, Pattern
from threading import Lock
from functools import partial
from typing import Iterator, List, Optional, Union, Dict
from typing import Callable, Coroutine, Iterator, List, Optional, Union, Dict
from typing_extensions import TypedDict, Literal
import llama_cpp
@ -10,8 +11,10 @@ import llama_cpp
import anyio
from anyio.streams.memory import MemoryObjectSendStream
from starlette.concurrency import run_in_threadpool, iterate_in_threadpool
from fastapi import Depends, FastAPI, APIRouter, Request
from fastapi import Depends, FastAPI, APIRouter, Request, Response
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from fastapi.routing import APIRoute
from pydantic import BaseModel, Field
from pydantic_settings import BaseSettings
from sse_starlette.sse import EventSourceResponse
@ -94,7 +97,190 @@ class Settings(BaseSettings):
)
router = APIRouter()
class ErrorResponse(TypedDict):
"""OpenAI style error response"""
message: str
type: str
param: Optional[str]
code: Optional[str]
class ErrorResponseFormatters:
"""Collection of formatters for error responses.
Args:
request (Union[CreateCompletionRequest, CreateChatCompletionRequest]):
Request body
match (Match[str]): Match object from regex pattern
Returns:
tuple[int, ErrorResponse]: Status code and error response
"""
@staticmethod
def context_length_exceeded(
request: Union[
"CreateCompletionRequest", "CreateChatCompletionRequest"
],
match: Match[str],
) -> tuple[int, ErrorResponse]:
"""Formatter for context length exceeded error"""
context_window = int(match.group(2))
prompt_tokens = int(match.group(1))
completion_tokens = request.max_tokens
if hasattr(request, "messages"):
# Chat completion
message = (
"This model's maximum context length is {} tokens. "
"However, you requested {} tokens "
"({} in the messages, {} in the completion). "
"Please reduce the length of the messages or completion."
)
else:
# Text completion
message = (
"This model's maximum context length is {} tokens, "
"however you requested {} tokens "
"({} in your prompt; {} for the completion). "
"Please reduce your prompt; or completion length."
)
return 400, ErrorResponse(
message=message.format(
context_window,
completion_tokens + prompt_tokens,
prompt_tokens,
completion_tokens,
),
type="invalid_request_error",
param="messages",
code="context_length_exceeded",
)
@staticmethod
def model_not_found(
request: Union[
"CreateCompletionRequest", "CreateChatCompletionRequest"
],
match: Match[str],
) -> tuple[int, ErrorResponse]:
"""Formatter for model_not_found error"""
model_path = str(match.group(1))
message = f"The model `{model_path}` does not exist"
return 400, ErrorResponse(
message=message,
type="invalid_request_error",
param=None,
code="model_not_found",
)
class RouteErrorHandler(APIRoute):
"""Custom APIRoute that handles application errors and exceptions"""
# key: regex pattern for original error message from llama_cpp
# value: formatter function
pattern_and_formatters: dict[
"Pattern",
Callable[
[
Union["CreateCompletionRequest", "CreateChatCompletionRequest"],
Match[str],
],
tuple[int, ErrorResponse],
],
] = {
compile(
r"Requested tokens \((\d+)\) exceed context window of (\d+)"
): ErrorResponseFormatters.context_length_exceeded,
compile(
r"Model path does not exist: (.+)"
): ErrorResponseFormatters.model_not_found,
}
def error_message_wrapper(
self,
error: Exception,
body: Optional[
Union[
"CreateChatCompletionRequest",
"CreateCompletionRequest",
"CreateEmbeddingRequest",
]
] = None,
) -> tuple[int, ErrorResponse]:
"""Wraps error message in OpenAI style error response"""
if body is not None and isinstance(
body,
(
CreateCompletionRequest,
CreateChatCompletionRequest,
),
):
# When text completion or chat completion
for pattern, callback in self.pattern_and_formatters.items():
match = pattern.search(str(error))
if match is not None:
return callback(body, match)
# Wrap other errors as internal server error
return 500, ErrorResponse(
message=str(error),
type="internal_server_error",
param=None,
code=None,
)
def get_route_handler(
self,
) -> Callable[[Request], Coroutine[None, None, Response]]:
"""Defines custom route handler that catches exceptions and formats
in OpenAI style error response"""
original_route_handler = super().get_route_handler()
async def custom_route_handler(request: Request) -> Response:
try:
return await original_route_handler(request)
except Exception as exc:
json_body = await request.json()
try:
if "messages" in json_body:
# Chat completion
body: Optional[
Union[
CreateChatCompletionRequest,
CreateCompletionRequest,
CreateEmbeddingRequest,
]
] = CreateChatCompletionRequest(**json_body)
elif "prompt" in json_body:
# Text completion
body = CreateCompletionRequest(**json_body)
else:
# Embedding
body = CreateEmbeddingRequest(**json_body)
except Exception:
# Invalid request body
body = None
# Get proper error message from the exception
(
status_code,
error_message,
) = self.error_message_wrapper(error=exc, body=body)
return JSONResponse(
{"error": error_message},
status_code=status_code,
)
return custom_route_handler
router = APIRouter(route_class=RouteErrorHandler)
settings: Optional[Settings] = None
llama: Optional[llama_cpp.Llama] = None
@ -183,10 +369,33 @@ def get_settings():
yield settings
async def get_event_publisher(
request: Request,
inner_send_chan: MemoryObjectSendStream,
iterator: Iterator,
):
async with inner_send_chan:
try:
async for chunk in iterate_in_threadpool(iterator):
await inner_send_chan.send(dict(data=json.dumps(chunk)))
if await request.is_disconnected():
raise anyio.get_cancelled_exc_class()()
if settings.interrupt_requests and llama_outer_lock.locked():
await inner_send_chan.send(dict(data="[DONE]"))
raise anyio.get_cancelled_exc_class()()
await inner_send_chan.send(dict(data="[DONE]"))
except anyio.get_cancelled_exc_class() as e:
print("disconnected")
with anyio.move_on_after(1, shield=True):
print(
f"Disconnected from client (via refresh/close) {request.client}"
)
raise e
model_field = Field(description="The model to use for generating completions.", default=None)
max_tokens_field = Field(
default=16, ge=1, le=2048, description="The maximum number of tokens to generate."
default=16, ge=1, description="The maximum number of tokens to generate."
)
temperature_field = Field(
@ -374,35 +583,31 @@ async def create_completion(
make_logit_bias_processor(llama, body.logit_bias, body.logit_bias_type),
])
if body.stream:
iterator_or_completion: Union[llama_cpp.Completion, Iterator[
llama_cpp.CompletionChunk
]] = await run_in_threadpool(llama, **kwargs)
if isinstance(iterator_or_completion, Iterator):
# EAFP: It's easier to ask for forgiveness than permission
first_response = await run_in_threadpool(next, iterator_or_completion)
# If no exception was raised from first_response, we can assume that
# the iterator is valid and we can use it to stream the response.
def iterator() -> Iterator[llama_cpp.CompletionChunk]:
yield first_response
yield from iterator_or_completion
send_chan, recv_chan = anyio.create_memory_object_stream(10)
async def event_publisher(inner_send_chan: MemoryObjectSendStream):
async with inner_send_chan:
try:
iterator: Iterator[llama_cpp.CompletionChunk] = await run_in_threadpool(llama, **kwargs) # type: ignore
async for chunk in iterate_in_threadpool(iterator):
await inner_send_chan.send(dict(data=json.dumps(chunk)))
if await request.is_disconnected():
raise anyio.get_cancelled_exc_class()()
if settings.interrupt_requests and llama_outer_lock.locked():
await inner_send_chan.send(dict(data="[DONE]"))
raise anyio.get_cancelled_exc_class()()
await inner_send_chan.send(dict(data="[DONE]"))
except anyio.get_cancelled_exc_class() as e:
print("disconnected")
with anyio.move_on_after(1, shield=True):
print(
f"Disconnected from client (via refresh/close) {request.client}"
)
raise e
return EventSourceResponse(
recv_chan, data_sender_callable=partial(event_publisher, send_chan)
) # type: ignore
recv_chan, data_sender_callable=partial( # type: ignore
get_event_publisher,
request=request,
inner_send_chan=send_chan,
iterator=iterator(),
)
)
else:
completion: llama_cpp.Completion = await run_in_threadpool(llama, **kwargs) # type: ignore
return completion
return iterator_or_completion
class CreateEmbeddingRequest(BaseModel):
@ -505,38 +710,31 @@ async def create_chat_completion(
make_logit_bias_processor(llama, body.logit_bias, body.logit_bias_type),
])
if body.stream:
iterator_or_completion: Union[llama_cpp.ChatCompletion, Iterator[
llama_cpp.ChatCompletionChunk
]] = await run_in_threadpool(llama.create_chat_completion, **kwargs)
if isinstance(iterator_or_completion, Iterator):
# EAFP: It's easier to ask for forgiveness than permission
first_response = await run_in_threadpool(next, iterator_or_completion)
# If no exception was raised from first_response, we can assume that
# the iterator is valid and we can use it to stream the response.
def iterator() -> Iterator[llama_cpp.ChatCompletionChunk]:
yield first_response
yield from iterator_or_completion
send_chan, recv_chan = anyio.create_memory_object_stream(10)
async def event_publisher(inner_send_chan: MemoryObjectSendStream):
async with inner_send_chan:
try:
iterator: Iterator[llama_cpp.ChatCompletionChunk] = await run_in_threadpool(llama.create_chat_completion, **kwargs) # type: ignore
async for chat_chunk in iterate_in_threadpool(iterator):
await inner_send_chan.send(dict(data=json.dumps(chat_chunk)))
if await request.is_disconnected():
raise anyio.get_cancelled_exc_class()()
if settings.interrupt_requests and llama_outer_lock.locked():
await inner_send_chan.send(dict(data="[DONE]"))
raise anyio.get_cancelled_exc_class()()
await inner_send_chan.send(dict(data="[DONE]"))
except anyio.get_cancelled_exc_class() as e:
print("disconnected")
with anyio.move_on_after(1, shield=True):
print(
f"Disconnected from client (via refresh/close) {request.client}"
)
raise e
return EventSourceResponse(
recv_chan,
data_sender_callable=partial(event_publisher, send_chan),
) # type: ignore
else:
completion: llama_cpp.ChatCompletion = await run_in_threadpool(
llama.create_chat_completion, **kwargs # type: ignore
recv_chan, data_sender_callable=partial( # type: ignore
get_event_publisher,
request=request,
inner_send_chan=send_chan,
iterator=iterator(),
)
)
return completion
else:
return iterator_or_completion
class ModelData(TypedDict):