group-wbl/.venv/lib/python3.13/site-packages/langchain_openai/llms/base.py

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"""Base classes for OpenAI large language models. Chat models are in `chat_models/`."""
from __future__ import annotations
import logging
import sys
from collections.abc import AsyncIterator, Callable, Collection, Iterator, Mapping
from typing import Any, Literal
import openai
import tiktoken
from langchain_core.callbacks import (
AsyncCallbackManagerForLLMRun,
CallbackManagerForLLMRun,
)
from langchain_core.language_models.llms import BaseLLM
from langchain_core.outputs import Generation, GenerationChunk, LLMResult
from langchain_core.utils import get_pydantic_field_names
from langchain_core.utils.utils import _build_model_kwargs, from_env, secret_from_env
from pydantic import ConfigDict, Field, SecretStr, model_validator
from typing_extensions import Self
logger = logging.getLogger(__name__)
def _update_token_usage(
keys: set[str], response: dict[str, Any], token_usage: dict[str, Any]
) -> None:
"""Update token usage."""
_keys_to_use = keys.intersection(response["usage"])
for _key in _keys_to_use:
if _key not in token_usage:
token_usage[_key] = response["usage"][_key]
else:
token_usage[_key] += response["usage"][_key]
def _stream_response_to_generation_chunk(
stream_response: dict[str, Any],
) -> GenerationChunk:
"""Convert a stream response to a generation chunk."""
if not stream_response["choices"]:
return GenerationChunk(text="")
return GenerationChunk(
text=stream_response["choices"][0]["text"] or "",
generation_info={
"finish_reason": stream_response["choices"][0].get("finish_reason", None),
"logprobs": stream_response["choices"][0].get("logprobs", None),
},
)
class BaseOpenAI(BaseLLM):
"""Base OpenAI large language model class.
Setup:
Install `langchain-openai` and set environment variable `OPENAI_API_KEY`.
```bash
pip install -U langchain-openai
export OPENAI_API_KEY="your-api-key"
```
Key init args completion params:
model_name:
Name of OpenAI model to use.
temperature:
Sampling temperature.
max_tokens:
Max number of tokens to generate.
top_p:
Total probability mass of tokens to consider at each step.
frequency_penalty:
Penalizes repeated tokens according to frequency.
presence_penalty:
Penalizes repeated tokens.
n:
How many completions to generate for each prompt.
best_of:
Generates best_of completions server-side and returns the "best".
logit_bias:
Adjust the probability of specific tokens being generated.
seed:
Seed for generation.
logprobs:
Include the log probabilities on the logprobs most likely output tokens.
streaming:
Whether to stream the results or not.
Key init args client params:
openai_api_key:
OpenAI API key. If not passed in will be read from env var
`OPENAI_API_KEY`.
openai_api_base:
Base URL path for API requests, leave blank if not using a proxy or
service emulator.
openai_organization:
OpenAI organization ID. If not passed in will be read from env
var `OPENAI_ORG_ID`.
request_timeout:
Timeout for requests to OpenAI completion API.
max_retries:
Maximum number of retries to make when generating.
batch_size:
Batch size to use when passing multiple documents to generate.
See full list of supported init args and their descriptions in the params section.
Instantiate:
```python
from langchain_openai.llms.base import BaseOpenAI
model = BaseOpenAI(
model_name="gpt-3.5-turbo-instruct",
temperature=0.7,
max_tokens=256,
top_p=1,
frequency_penalty=0,
presence_penalty=0,
# openai_api_key="...",
# openai_api_base="...",
# openai_organization="...",
# other params...
)
```
Invoke:
```python
input_text = "The meaning of life is "
response = model.invoke(input_text)
print(response)
```
```txt
"a philosophical question that has been debated by thinkers and
scholars for centuries."
```
Stream:
```python
for chunk in model.stream(input_text):
print(chunk, end="")
```
```txt
a philosophical question that has been debated by thinkers and
scholars for centuries.
```
Async:
```python
response = await model.ainvoke(input_text)
# stream:
# async for chunk in model.astream(input_text):
# print(chunk, end="")
# batch:
# await model.abatch([input_text])
```
```
"a philosophical question that has been debated by thinkers and
scholars for centuries."
```
"""
client: Any = Field(default=None, exclude=True)
async_client: Any = Field(default=None, exclude=True)
model_name: str = Field(default="gpt-3.5-turbo-instruct", alias="model")
"""Model name to use."""
temperature: float = 0.7
"""What sampling temperature to use."""
max_tokens: int = 256
"""The maximum number of tokens to generate in the completion.
-1 returns as many tokens as possible given the prompt and
the models maximal context size."""
top_p: float = 1
"""Total probability mass of tokens to consider at each step."""
frequency_penalty: float = 0
"""Penalizes repeated tokens according to frequency."""
presence_penalty: float = 0
"""Penalizes repeated tokens."""
n: int = 1
"""How many completions to generate for each prompt."""
best_of: int = 1
"""Generates best_of completions server-side and returns the "best"."""
model_kwargs: dict[str, Any] = Field(default_factory=dict)
"""Holds any model parameters valid for `create` call not explicitly specified."""
openai_api_key: SecretStr | None | Callable[[], str] = Field(
alias="api_key", default_factory=secret_from_env("OPENAI_API_KEY", default=None)
)
"""Automatically inferred from env var `OPENAI_API_KEY` if not provided."""
openai_api_base: str | None = Field(
alias="base_url", default_factory=from_env("OPENAI_API_BASE", default=None)
)
"""Base URL path for API requests, leave blank if not using a proxy or service
emulator."""
openai_organization: str | None = Field(
alias="organization",
default_factory=from_env(
["OPENAI_ORG_ID", "OPENAI_ORGANIZATION"], default=None
),
)
"""Automatically inferred from env var `OPENAI_ORG_ID` if not provided."""
# to support explicit proxy for OpenAI
openai_proxy: str | None = Field(
default_factory=from_env("OPENAI_PROXY", default=None)
)
batch_size: int = 20
"""Batch size to use when passing multiple documents to generate."""
request_timeout: float | tuple[float, float] | Any | None = Field(
default=None, alias="timeout"
)
"""Timeout for requests to OpenAI completion API. Can be float, `httpx.Timeout` or
None."""
logit_bias: dict[str, float] | None = None
"""Adjust the probability of specific tokens being generated."""
max_retries: int = 2
"""Maximum number of retries to make when generating."""
seed: int | None = None
"""Seed for generation"""
logprobs: int | None = None
"""Include the log probabilities on the logprobs most likely output tokens,
as well the chosen tokens."""
streaming: bool = False
"""Whether to stream the results or not."""
allowed_special: Literal["all"] | set[str] = set()
"""Set of special tokens that are allowed。"""
disallowed_special: Literal["all"] | Collection[str] = "all"
"""Set of special tokens that are not allowed。"""
tiktoken_model_name: str | None = None
"""The model name to pass to tiktoken when using this class.
Tiktoken is used to count the number of tokens in documents to constrain
them to be under a certain limit.
By default, when set to `None`, this will be the same as the embedding model name.
However, there are some cases where you may want to use this `Embedding` class with
a model name not supported by tiktoken. This can include when using Azure embeddings
or when using one of the many model providers that expose an OpenAI-like
API but with different models. In those cases, in order to avoid erroring
when tiktoken is called, you can specify a model name to use here.
"""
default_headers: Mapping[str, str] | None = None
default_query: Mapping[str, object] | None = None
# Configure a custom httpx client. See the
# [httpx documentation](https://www.python-httpx.org/api/#client) for more details.
http_client: Any | None = None
"""Optional `httpx.Client`.
Only used for sync invocations. Must specify `http_async_client` as well if you'd
like a custom client for async invocations.
"""
http_async_client: Any | None = None
"""Optional `httpx.AsyncClient`.
Only used for async invocations. Must specify `http_client` as well if you'd like a
custom client for sync invocations.
"""
extra_body: Mapping[str, Any] | None = None
"""Optional additional JSON properties to include in the request parameters when
making requests to OpenAI compatible APIs, such as vLLM."""
model_config = ConfigDict(populate_by_name=True)
@model_validator(mode="before")
@classmethod
def build_extra(cls, values: dict[str, Any]) -> Any:
"""Build extra kwargs from additional params that were passed in."""
all_required_field_names = get_pydantic_field_names(cls)
return _build_model_kwargs(values, all_required_field_names)
@model_validator(mode="after")
def validate_environment(self) -> Self:
"""Validate that api key and python package exists in environment."""
if self.n < 1:
msg = "n must be at least 1."
raise ValueError(msg)
if self.streaming and self.n > 1:
msg = "Cannot stream results when n > 1."
raise ValueError(msg)
if self.streaming and self.best_of > 1:
msg = "Cannot stream results when best_of > 1."
raise ValueError(msg)
# Resolve API key from SecretStr or Callable
api_key_value: str | Callable[[], str] | None = None
if self.openai_api_key is not None:
if isinstance(self.openai_api_key, SecretStr):
api_key_value = self.openai_api_key.get_secret_value()
elif callable(self.openai_api_key):
api_key_value = self.openai_api_key
client_params: dict = {
"api_key": api_key_value,
"organization": self.openai_organization,
"base_url": self.openai_api_base,
"timeout": self.request_timeout,
"max_retries": self.max_retries,
"default_headers": self.default_headers,
"default_query": self.default_query,
}
if not self.client:
sync_specific = {"http_client": self.http_client}
self.client = openai.OpenAI(**client_params, **sync_specific).completions # type: ignore[arg-type]
if not self.async_client:
async_specific = {"http_client": self.http_async_client}
self.async_client = openai.AsyncOpenAI(
**client_params,
**async_specific, # type: ignore[arg-type]
).completions
return self
@property
def _default_params(self) -> dict[str, Any]:
"""Get the default parameters for calling OpenAI API."""
normal_params: dict[str, Any] = {
"temperature": self.temperature,
"top_p": self.top_p,
"frequency_penalty": self.frequency_penalty,
"presence_penalty": self.presence_penalty,
"n": self.n,
"seed": self.seed,
"logprobs": self.logprobs,
}
if self.logit_bias is not None:
normal_params["logit_bias"] = self.logit_bias
if self.max_tokens is not None:
normal_params["max_tokens"] = self.max_tokens
if self.extra_body is not None:
normal_params["extra_body"] = self.extra_body
# Azure gpt-35-turbo doesn't support best_of
# don't specify best_of if it is 1
if self.best_of > 1:
normal_params["best_of"] = self.best_of
return {**normal_params, **self.model_kwargs}
def _stream(
self,
prompt: str,
stop: list[str] | None = None,
run_manager: CallbackManagerForLLMRun | None = None,
**kwargs: Any,
) -> Iterator[GenerationChunk]:
params = {**self._invocation_params, **kwargs, "stream": True}
self.get_sub_prompts(params, [prompt], stop) # this mutates params
for stream_resp in self.client.create(prompt=prompt, **params):
if not isinstance(stream_resp, dict):
stream_resp = stream_resp.model_dump()
chunk = _stream_response_to_generation_chunk(stream_resp)
if run_manager:
run_manager.on_llm_new_token(
chunk.text,
chunk=chunk,
verbose=self.verbose,
logprobs=(
chunk.generation_info["logprobs"]
if chunk.generation_info
else None
),
)
yield chunk
async def _astream(
self,
prompt: str,
stop: list[str] | None = None,
run_manager: AsyncCallbackManagerForLLMRun | None = None,
**kwargs: Any,
) -> AsyncIterator[GenerationChunk]:
params = {**self._invocation_params, **kwargs, "stream": True}
self.get_sub_prompts(params, [prompt], stop) # this mutates params
async for stream_resp in await self.async_client.create(
prompt=prompt, **params
):
if not isinstance(stream_resp, dict):
stream_resp = stream_resp.model_dump()
chunk = _stream_response_to_generation_chunk(stream_resp)
if run_manager:
await run_manager.on_llm_new_token(
chunk.text,
chunk=chunk,
verbose=self.verbose,
logprobs=(
chunk.generation_info["logprobs"]
if chunk.generation_info
else None
),
)
yield chunk
def _generate(
self,
prompts: list[str],
stop: list[str] | None = None,
run_manager: CallbackManagerForLLMRun | None = None,
**kwargs: Any,
) -> LLMResult:
"""Call out to OpenAI's endpoint with k unique prompts.
Args:
prompts: The prompts to pass into the model.
stop: Optional list of stop words to use when generating.
run_manager: Optional callback manager to use for the call.
Returns:
The full LLM output.
Example:
```python
response = openai.generate(["Tell me a joke."])
```
"""
# TODO: write a unit test for this
params = self._invocation_params
params = {**params, **kwargs}
sub_prompts = self.get_sub_prompts(params, prompts, stop)
choices = []
token_usage: dict[str, int] = {}
# Get the token usage from the response.
# Includes prompt, completion, and total tokens used.
_keys = {"completion_tokens", "prompt_tokens", "total_tokens"}
system_fingerprint: str | None = None
for _prompts in sub_prompts:
if self.streaming:
if len(_prompts) > 1:
msg = "Cannot stream results with multiple prompts."
raise ValueError(msg)
generation: GenerationChunk | None = None
for chunk in self._stream(_prompts[0], stop, run_manager, **kwargs):
if generation is None:
generation = chunk
else:
generation += chunk
if generation is None:
msg = "Generation is empty after streaming."
raise ValueError(msg)
choices.append(
{
"text": generation.text,
"finish_reason": (
generation.generation_info.get("finish_reason")
if generation.generation_info
else None
),
"logprobs": (
generation.generation_info.get("logprobs")
if generation.generation_info
else None
),
}
)
else:
response = self.client.create(prompt=_prompts, **params)
if not isinstance(response, dict):
# V1 client returns the response in an PyDantic object instead of
# dict. For the transition period, we deep convert it to dict.
response = response.model_dump()
# Sometimes the AI Model calling will get error, we should raise it.
# Otherwise, the next code 'choices.extend(response["choices"])'
# will throw a "TypeError: 'NoneType' object is not iterable" error
# to mask the true error. Because 'response["choices"]' is None.
if response.get("error"):
raise ValueError(response.get("error"))
choices.extend(response["choices"])
_update_token_usage(_keys, response, token_usage)
if not system_fingerprint:
system_fingerprint = response.get("system_fingerprint")
return self.create_llm_result(
choices, prompts, params, token_usage, system_fingerprint=system_fingerprint
)
async def _agenerate(
self,
prompts: list[str],
stop: list[str] | None = None,
run_manager: AsyncCallbackManagerForLLMRun | None = None,
**kwargs: Any,
) -> LLMResult:
"""Call out to OpenAI's endpoint async with k unique prompts."""
params = self._invocation_params
params = {**params, **kwargs}
sub_prompts = self.get_sub_prompts(params, prompts, stop)
choices = []
token_usage: dict[str, int] = {}
# Get the token usage from the response.
# Includes prompt, completion, and total tokens used.
_keys = {"completion_tokens", "prompt_tokens", "total_tokens"}
system_fingerprint: str | None = None
for _prompts in sub_prompts:
if self.streaming:
if len(_prompts) > 1:
msg = "Cannot stream results with multiple prompts."
raise ValueError(msg)
generation: GenerationChunk | None = None
async for chunk in self._astream(
_prompts[0], stop, run_manager, **kwargs
):
if generation is None:
generation = chunk
else:
generation += chunk
if generation is None:
msg = "Generation is empty after streaming."
raise ValueError(msg)
choices.append(
{
"text": generation.text,
"finish_reason": (
generation.generation_info.get("finish_reason")
if generation.generation_info
else None
),
"logprobs": (
generation.generation_info.get("logprobs")
if generation.generation_info
else None
),
}
)
else:
response = await self.async_client.create(prompt=_prompts, **params)
if not isinstance(response, dict):
response = response.model_dump()
choices.extend(response["choices"])
_update_token_usage(_keys, response, token_usage)
return self.create_llm_result(
choices, prompts, params, token_usage, system_fingerprint=system_fingerprint
)
def get_sub_prompts(
self,
params: dict[str, Any],
prompts: list[str],
stop: list[str] | None = None,
) -> list[list[str]]:
"""Get the sub prompts for llm call."""
if stop is not None:
params["stop"] = stop
if params["max_tokens"] == -1:
if len(prompts) != 1:
msg = "max_tokens set to -1 not supported for multiple inputs."
raise ValueError(msg)
params["max_tokens"] = self.max_tokens_for_prompt(prompts[0])
return [
prompts[i : i + self.batch_size]
for i in range(0, len(prompts), self.batch_size)
]
def create_llm_result(
self,
choices: Any,
prompts: list[str],
params: dict[str, Any],
token_usage: dict[str, int],
*,
system_fingerprint: str | None = None,
) -> LLMResult:
"""Create the LLMResult from the choices and prompts."""
generations = []
n = params.get("n", self.n)
for i, _ in enumerate(prompts):
sub_choices = choices[i * n : (i + 1) * n]
generations.append(
[
Generation(
text=choice["text"],
generation_info={
"finish_reason": choice.get("finish_reason"),
"logprobs": choice.get("logprobs"),
},
)
for choice in sub_choices
]
)
llm_output = {"token_usage": token_usage, "model_name": self.model_name}
if system_fingerprint:
llm_output["system_fingerprint"] = system_fingerprint
return LLMResult(generations=generations, llm_output=llm_output)
@property
def _invocation_params(self) -> dict[str, Any]:
"""Get the parameters used to invoke the model."""
return self._default_params
@property
def _identifying_params(self) -> Mapping[str, Any]:
"""Get the identifying parameters."""
return {"model_name": self.model_name, **self._default_params}
@property
def _llm_type(self) -> str:
"""Return type of llm."""
return "openai"
def get_token_ids(self, text: str) -> list[int]:
"""Get the token IDs using the tiktoken package."""
if self.custom_get_token_ids is not None:
return self.custom_get_token_ids(text)
# tiktoken NOT supported for Python < 3.8
if sys.version_info[1] < 8:
return super().get_num_tokens(text)
model_name = self.tiktoken_model_name or self.model_name
try:
enc = tiktoken.encoding_for_model(model_name)
except KeyError:
enc = tiktoken.get_encoding("cl100k_base")
return enc.encode(
text,
allowed_special=self.allowed_special,
disallowed_special=self.disallowed_special,
)
@staticmethod
def modelname_to_contextsize(modelname: str) -> int:
"""Calculate the maximum number of tokens possible to generate for a model.
Args:
modelname: The modelname we want to know the context size for.
Returns:
The maximum context size
Example:
```python
max_tokens = openai.modelname_to_contextsize("gpt-3.5-turbo-instruct")
```
"""
model_token_mapping = {
"gpt-4o-mini": 128_000,
"gpt-4o": 128_000,
"gpt-4o-2024-05-13": 128_000,
"gpt-4": 8192,
"gpt-4-0314": 8192,
"gpt-4-0613": 8192,
"gpt-4-32k": 32768,
"gpt-4-32k-0314": 32768,
"gpt-4-32k-0613": 32768,
"gpt-3.5-turbo": 4096,
"gpt-3.5-turbo-0301": 4096,
"gpt-3.5-turbo-0613": 4096,
"gpt-3.5-turbo-16k": 16385,
"gpt-3.5-turbo-16k-0613": 16385,
"gpt-3.5-turbo-instruct": 4096,
"text-ada-001": 2049,
"ada": 2049,
"text-babbage-001": 2040,
"babbage": 2049,
"text-curie-001": 2049,
"curie": 2049,
"davinci": 2049,
"text-davinci-003": 4097,
"text-davinci-002": 4097,
"code-davinci-002": 8001,
"code-davinci-001": 8001,
"code-cushman-002": 2048,
"code-cushman-001": 2048,
}
# handling finetuned models
if "ft-" in modelname:
modelname = modelname.split(":")[0]
context_size = model_token_mapping.get(modelname)
if context_size is None:
raise ValueError(
f"Unknown model: {modelname}. Please provide a valid OpenAI model name."
"Known models are: " + ", ".join(model_token_mapping.keys())
)
return context_size
@property
def max_context_size(self) -> int:
"""Get max context size for this model."""
return self.modelname_to_contextsize(self.model_name)
def max_tokens_for_prompt(self, prompt: str) -> int:
"""Calculate the maximum number of tokens possible to generate for a prompt.
Args:
prompt: The prompt to pass into the model.
Returns:
The maximum number of tokens to generate for a prompt.
Example:
```python
max_tokens = openai.max_tokens_for_prompt("Tell me a joke.")
```
"""
num_tokens = self.get_num_tokens(prompt)
return self.max_context_size - num_tokens
class OpenAI(BaseOpenAI):
"""OpenAI completion model integration.
Setup:
Install `langchain-openai` and set environment variable `OPENAI_API_KEY`.
```bash
pip install -U langchain-openai
export OPENAI_API_KEY="your-api-key"
```
Key init args completion params:
model:
Name of OpenAI model to use.
temperature:
Sampling temperature.
max_tokens:
Max number of tokens to generate.
logprobs:
Whether to return logprobs.
stream_options:
Configure streaming outputs, like whether to return token usage when
streaming (`{"include_usage": True}`).
Key init args client params:
timeout:
Timeout for requests.
max_retries:
Max number of retries.
api_key:
OpenAI API key. If not passed in will be read from env var `OPENAI_API_KEY`.
base_url:
Base URL for API requests. Only specify if using a proxy or service
emulator.
organization:
OpenAI organization ID. If not passed in will be read from env
var `OPENAI_ORG_ID`.
See full list of supported init args and their descriptions in the params section.
Instantiate:
```python
from langchain_openai import OpenAI
model = OpenAI(
model="gpt-3.5-turbo-instruct",
temperature=0,
max_retries=2,
# api_key="...",
# base_url="...",
# organization="...",
# other params...
)
```
Invoke:
```python
input_text = "The meaning of life is "
model.invoke(input_text)
```
```txt
"a philosophical question that has been debated by thinkers and scholars for centuries."
```
Stream:
```python
for chunk in model.stream(input_text):
print(chunk, end="|")
```
```txt
a| philosophical| question| that| has| been| debated| by| thinkers| and| scholars| for| centuries|.
```
```python
"".join(model.stream(input_text))
```
```txt
"a philosophical question that has been debated by thinkers and scholars for centuries."
```
Async:
```python
await model.ainvoke(input_text)
# stream:
# async for chunk in (await model.astream(input_text)):
# print(chunk)
# batch:
# await model.abatch([input_text])
```
```txt
"a philosophical question that has been debated by thinkers and scholars for centuries."
```
""" # noqa: E501
@classmethod
def get_lc_namespace(cls) -> list[str]:
"""Get the namespace of the LangChain object.
Returns:
`["langchain", "llms", "openai"]`
"""
return ["langchain", "llms", "openai"]
@classmethod
def is_lc_serializable(cls) -> bool:
"""Return whether this model can be serialized by LangChain."""
return True
@property
def _invocation_params(self) -> dict[str, Any]:
return {"model": self.model_name, **super()._invocation_params}
@property
def lc_secrets(self) -> dict[str, str]:
"""Mapping of secret keys to environment variables."""
return {"openai_api_key": "OPENAI_API_KEY"}
@property
def lc_attributes(self) -> dict[str, Any]:
"""LangChain attributes for this class."""
attributes: dict[str, Any] = {}
if self.openai_api_base:
attributes["openai_api_base"] = self.openai_api_base
if self.openai_organization:
attributes["openai_organization"] = self.openai_organization
if self.openai_proxy:
attributes["openai_proxy"] = self.openai_proxy
return attributes