_base_client.py

from __future__ import annotations

import json
import time
import uuid
import email
import asyncio
import inspect
import logging
import platform
import warnings
import email.utils
from types import TracebackType
from random import random
from typing import (
    TYPE_CHECKING,
    Any,
    Dict,
    Type,
    Union,
    Generic,
    Mapping,
    TypeVar,
    Iterable,
    Iterator,
    Optional,
    Generator,
    AsyncIterator,
    cast,
    overload,
)
from functools import lru_cache
from typing_extensions import Literal, override, get_origin

import anyio
import httpx
import distro
import pydantic
from httpx import URL, Limits
from pydantic import PrivateAttr

from . import _exceptions
from ._qs import Querystring
from ._files import to_httpx_files, async_to_httpx_files
from ._types import (
    NOT_GIVEN,
    Body,
    Omit,
    Query,
    Headers,
    Timeout,
    NotGiven,
    ResponseT,
    Transport,
    AnyMapping,
    PostParser,
    ProxiesTypes,
    RequestFiles,
    HttpxSendArgs,
    AsyncTransport,
    RequestOptions,
    ModelBuilderProtocol,
)
from ._utils import is_dict, is_given, is_mapping
from ._compat import model_copy, model_dump
from ._models import GenericModel, FinalRequestOptions, validate_type, construct_type
from ._response import (
    APIResponse,
    BaseAPIResponse,
    AsyncAPIResponse,
    extract_response_type,
)
from ._constants import (
    DEFAULT_LIMITS,
    DEFAULT_TIMEOUT,
    MAX_RETRY_DELAY,
    DEFAULT_MAX_RETRIES,
    INITIAL_RETRY_DELAY,
    RAW_RESPONSE_HEADER,
    OVERRIDE_CAST_TO_HEADER,
)
from ._streaming import Stream, AsyncStream
from ._exceptions import (
    APIStatusError,
    APITimeoutError,
    APIConnectionError,
    APIResponseValidationError,
)
from ._legacy_response import LegacyAPIResponse

log: logging.Logger = logging.getLogger(__name__)

# TODO: make base page type vars covariant
SyncPageT = TypeVar("SyncPageT", bound="BaseSyncPage[Any]")
AsyncPageT = TypeVar("AsyncPageT", bound="BaseAsyncPage[Any]")


_T = TypeVar("_T")
_T_co = TypeVar("_T_co", covariant=True)

_StreamT = TypeVar("_StreamT", bound=Stream[Any])
_AsyncStreamT = TypeVar("_AsyncStreamT", bound=AsyncStream[Any])

if TYPE_CHECKING:
    from httpx._config import DEFAULT_TIMEOUT_CONFIG as HTTPX_DEFAULT_TIMEOUT
else:
    try:
        from httpx._config import DEFAULT_TIMEOUT_CONFIG as HTTPX_DEFAULT_TIMEOUT
    except ImportError:
        # taken from https://github.com/encode/httpx/blob/3ba5fe0d7ac70222590e759c31442b1cab263791/httpx/_config.py#L366
        HTTPX_DEFAULT_TIMEOUT = Timeout(5.0)


class PageInfo:
    """Stores the necessary information to build the request to retrieve the next page.

    Either `url` or `params` must be set.
    """

    url: URL | NotGiven
    params: Query | NotGiven

    @overload
    def __init__(
        self,
        *,
        url: URL,
    ) -> None:
        ...

    @overload
    def __init__(
        self,
        *,
        params: Query,
    ) -> None:
        ...

    def __init__(
        self,
        *,
        url: URL | NotGiven = NOT_GIVEN,
        params: Query | NotGiven = NOT_GIVEN,
    ) -> None:
        self.url = url
        self.params = params


class BasePage(GenericModel, Generic[_T]):
    """
    Defines the core interface for pagination.

    Type Args:
        ModelT: The pydantic model that represents an item in the response.

    Methods:
        has_next_page(): Check if there is another page available
        next_page_info(): Get the necessary information to make a request for the next page
    """

    _options: FinalRequestOptions = PrivateAttr()
    _model: Type[_T] = PrivateAttr()

    def has_next_page(self) -> bool:
        items = self._get_page_items()
        if not items:
            return False
        return self.next_page_info() is not None

    def next_page_info(self) -> Optional[PageInfo]:
        ...

    def _get_page_items(self) -> Iterable[_T]:  # type: ignore[empty-body]
        ...

    def _params_from_url(self, url: URL) -> httpx.QueryParams:
        # TODO: do we have to preprocess params here?
        return httpx.QueryParams(cast(Any, self._options.params)).merge(url.params)

    def _info_to_options(self, info: PageInfo) -> FinalRequestOptions:
        options = model_copy(self._options)
        options._strip_raw_response_header()

        if not isinstance(info.params, NotGiven):
            options.params = {**options.params, **info.params}
            return options

        if not isinstance(info.url, NotGiven):
            params = self._params_from_url(info.url)
            url = info.url.copy_with(params=params)
            options.params = dict(url.params)
            options.url = str(url)
            return options

        raise ValueError("Unexpected PageInfo state")


class BaseSyncPage(BasePage[_T], Generic[_T]):
    _client: SyncAPIClient = pydantic.PrivateAttr()

    def _set_private_attributes(
        self,
        client: SyncAPIClient,
        model: Type[_T],
        options: FinalRequestOptions,
    ) -> None:
        self._model = model
        self._client = client
        self._options = options

    # Pydantic uses a custom `__iter__` method to support casting BaseModels
    # to dictionaries. e.g. dict(model).
    # As we want to support `for item in page`, this is inherently incompatible
    # with the default pydantic behaviour. It is not possible to support both
    # use cases at once. Fortunately, this is not a big deal as all other pydantic
    # methods should continue to work as expected as there is an alternative method
    # to cast a model to a dictionary, model.dict(), which is used internally
    # by pydantic.
    def __iter__(self) -> Iterator[_T]:  # type: ignore
        for page in self.iter_pages():
            for item in page._get_page_items():
                yield item

    def iter_pages(self: SyncPageT) -> Iterator[SyncPageT]:
        page = self
        while True:
            yield page
            if page.has_next_page():
                page = page.get_next_page()
            else:
                return

    def get_next_page(self: SyncPageT) -> SyncPageT:
        info = self.next_page_info()
        if not info:
            raise RuntimeError(
                "No next page expected; please check `.has_next_page()` before calling `.get_next_page()`."
            )

        options = self._info_to_options(info)
        return self._client._request_api_list(self._model, page=self.__class__, options=options)


class AsyncPaginator(Generic[_T, AsyncPageT]):
    def __init__(
        self,
        client: AsyncAPIClient,
        options: FinalRequestOptions,
        page_cls: Type[AsyncPageT],
        model: Type[_T],
    ) -> None:
        self._model = model
        self._client = client
        self._options = options
        self._page_cls = page_cls

    def __await__(self) -> Generator[Any, None, AsyncPageT]:
        return self._get_page().__await__()

    async def _get_page(self) -> AsyncPageT:
        def _parser(resp: AsyncPageT) -> AsyncPageT:
            resp._set_private_attributes(
                model=self._model,
                options=self._options,
                client=self._client,
            )
            return resp

        self._options.post_parser = _parser

        return await self._client.request(self._page_cls, self._options)

    async def __aiter__(self) -> AsyncIterator[_T]:
        # https://github.com/microsoft/pyright/issues/3464
        page = cast(
            AsyncPageT,
            await self,  # type: ignore
        )
        async for item in page:
            yield item


class BaseAsyncPage(BasePage[_T], Generic[_T]):
    _client: AsyncAPIClient = pydantic.PrivateAttr()

    def _set_private_attributes(
        self,
        model: Type[_T],
        client: AsyncAPIClient,
        options: FinalRequestOptions,
    ) -> None:
        self._model = model
        self._client = client
        self._options = options

    async def __aiter__(self) -> AsyncIterator[_T]:
        async for page in self.iter_pages():
            for item in page._get_page_items():
                yield item

    async def iter_pages(self: AsyncPageT) -> AsyncIterator[AsyncPageT]:
        page = self
        while True:
            yield page
            if page.has_next_page():
                page = await page.get_next_page()
            else:
                return

    async def get_next_page(self: AsyncPageT) -> AsyncPageT:
        info = self.next_page_info()
        if not info:
            raise RuntimeError(
                "No next page expected; please check `.has_next_page()` before calling `.get_next_page()`."
            )

        options = self._info_to_options(info)
        return await self._client._request_api_list(self._model, page=self.__class__, options=options)


_HttpxClientT = TypeVar("_HttpxClientT", bound=Union[httpx.Client, httpx.AsyncClient])
_DefaultStreamT = TypeVar("_DefaultStreamT", bound=Union[Stream[Any], AsyncStream[Any]])


class BaseClient(Generic[_HttpxClientT, _DefaultStreamT]):
    _client: _HttpxClientT
    _version: str
    _base_url: URL
    max_retries: int
    timeout: Union[float, Timeout, None]
    _limits: httpx.Limits
    _proxies: ProxiesTypes | None
    _transport: Transport | AsyncTransport | None
    _strict_response_validation: bool
    _idempotency_header: str | None
    _default_stream_cls: type[_DefaultStreamT] | None = None

    def __init__(
        self,
        *,
        version: str,
        base_url: str | URL,
        _strict_response_validation: bool,
        max_retries: int = DEFAULT_MAX_RETRIES,
        timeout: float | Timeout | None = DEFAULT_TIMEOUT,
        limits: httpx.Limits,
        transport: Transport | AsyncTransport | None,
        proxies: ProxiesTypes | None,
        custom_headers: Mapping[str, str] | None = None,
        custom_query: Mapping[str, object] | None = None,
    ) -> None:
        self._version = version
        self._base_url = self._enforce_trailing_slash(URL(base_url))
        self.max_retries = max_retries
        self.timeout = timeout
        self._limits = limits
        self._proxies = proxies
        self._transport = transport
        self._custom_headers = custom_headers or {}
        self._custom_query = custom_query or {}
        self._strict_response_validation = _strict_response_validation
        self._idempotency_header = None

    def _enforce_trailing_slash(self, url: URL) -> URL:
        if url.raw_path.endswith(b"/"):
            return url
        return url.copy_with(raw_path=url.raw_path + b"/")

    def _make_status_error_from_response(
        self,
        response: httpx.Response,
    ) -> APIStatusError:
        if response.is_closed and not response.is_stream_consumed:
            # We can't read the response body as it has been closed
            # before it was read. This can happen if an event hook
            # raises a status error.
            body = None
            err_msg = f"Error code: {response.status_code}"
        else:
            err_text = response.text.strip()
            body = err_text

            try:
                body = json.loads(err_text)
                err_msg = f"Error code: {response.status_code} - {body}"
            except Exception:
                err_msg = err_text or f"Error code: {response.status_code}"

        return self._make_status_error(err_msg, body=body, response=response)

    def _make_status_error(
        self,
        err_msg: str,
        *,
        body: object,
        response: httpx.Response,
    ) -> _exceptions.APIStatusError:
        raise NotImplementedError()

    def _remaining_retries(
        self,
        remaining_retries: Optional[int],
        options: FinalRequestOptions,
    ) -> int:
        return remaining_retries if remaining_retries is not None else options.get_max_retries(self.max_retries)

    def _build_headers(self, options: FinalRequestOptions) -> httpx.Headers:
        custom_headers = options.headers or {}
        headers_dict = _merge_mappings(self.default_headers, custom_headers)
        self._validate_headers(headers_dict, custom_headers)

        # headers are case-insensitive while dictionaries are not.
        headers = httpx.Headers(headers_dict)

        idempotency_header = self._idempotency_header
        if idempotency_header and options.method.lower() != "get" and idempotency_header not in headers:
            headers[idempotency_header] = options.idempotency_key or self._idempotency_key()

        return headers

    def _prepare_url(self, url: str) -> URL:
        """
        Merge a URL argument together with any 'base_url' on the client,
        to create the URL used for the outgoing request.
        """
        # Copied from httpx's `_merge_url` method.
        merge_url = URL(url)
        if merge_url.is_relative_url:
            merge_raw_path = self.base_url.raw_path + merge_url.raw_path.lstrip(b"/")
            return self.base_url.copy_with(raw_path=merge_raw_path)

        return merge_url

    def _build_request(
        self,
        options: FinalRequestOptions,
    ) -> httpx.Request:
        if log.isEnabledFor(logging.DEBUG):
            log.debug("Request options: %s", model_dump(options, exclude_unset=True))

        kwargs: dict[str, Any] = {}

        json_data = options.json_data
        if options.extra_json is not None:
            if json_data is None:
                json_data = cast(Body, options.extra_json)
            elif is_mapping(json_data):
                json_data = _merge_mappings(json_data, options.extra_json)
            else:
                raise RuntimeError(f"Unexpected JSON data type, {type(json_data)}, cannot merge with `extra_body`")

        headers = self._build_headers(options)
        params = _merge_mappings(self._custom_query, options.params)

        # If the given Content-Type header is multipart/form-data then it
        # has to be removed so that httpx can generate the header with
        # additional information for us as it has to be in this form
        # for the server to be able to correctly parse the request:
        # multipart/form-data; boundary=---abc--
        if headers.get("Content-Type") == "multipart/form-data":
            headers.pop("Content-Type")

            # As we are now sending multipart/form-data instead of application/json
            # we need to tell httpx to use it, https://www.python-httpx.org/advanced/#multipart-file-encoding
            if json_data:
                if not is_dict(json_data):
                    raise TypeError(
                        f"Expected query input to be a dictionary for multipart requests but got {type(json_data)} instead."
                    )
                kwargs["data"] = self._serialize_multipartform(json_data)

        # TODO: report this error to httpx
        return self._client.build_request(  # pyright: ignore[reportUnknownMemberType]
            headers=headers,
            timeout=self.timeout if isinstance(options.timeout, NotGiven) else options.timeout,
            method=options.method,
            url=self._prepare_url(options.url),
            # the `Query` type that we use is incompatible with qs'
            # `Params` type as it needs to be typed as `Mapping[str, object]`
            # so that passing a `TypedDict` doesn't cause an error.
            # https://github.com/microsoft/pyright/issues/3526#event-6715453066
            params=self.qs.stringify(cast(Mapping[str, Any], params)) if params else None,
            json=json_data,
            files=options.files,
            **kwargs,
        )

    def _serialize_multipartform(self, data: Mapping[object, object]) -> dict[str, object]:
        items = self.qs.stringify_items(
            # TODO: type ignore is required as stringify_items is well typed but we can't be
            # well typed without heavy validation.
            data,  # type: ignore
            array_format="brackets",
        )
        serialized: dict[str, object] = {}
        for key, value in items:
            if key in serialized:
                raise ValueError(f"Duplicate key encountered: {key}; This behaviour is not supported")
            serialized[key] = value
        return serialized

    def _maybe_override_cast_to(self, cast_to: type[ResponseT], options: FinalRequestOptions) -> type[ResponseT]:
        if not is_given(options.headers):
            return cast_to

        # make a copy of the headers so we don't mutate user-input
        headers = dict(options.headers)

        # we internally support defining a temporary header to override the
        # default `cast_to` type for use with `.with_raw_response` and `.with_streaming_response`
        # see _response.py for implementation details
        override_cast_to = headers.pop(OVERRIDE_CAST_TO_HEADER, NOT_GIVEN)
        if is_given(override_cast_to):
            options.headers = headers
            return cast(Type[ResponseT], override_cast_to)

        return cast_to

    def _should_stream_response_body(self, request: httpx.Request) -> bool:
        return request.headers.get(RAW_RESPONSE_HEADER) == "stream"  # type: ignore[no-any-return]

    def _process_response_data(
        self,
        *,
        data: object,
        cast_to: type[ResponseT],
        response: httpx.Response,
    ) -> ResponseT:
        if data is None:
            return cast(ResponseT, None)

        if cast_to is object:
            return cast(ResponseT, data)

        try:
            if inspect.isclass(cast_to) and issubclass(cast_to, ModelBuilderProtocol):
                return cast(ResponseT, cast_to.build(response=response, data=data))

            if self._strict_response_validation:
                return cast(ResponseT, validate_type(type_=cast_to, value=data))

            return cast(ResponseT, construct_type(type_=cast_to, value=data))
        except pydantic.ValidationError as err:
            raise APIResponseValidationError(response=response, body=data) from err

    @property
    def qs(self) -> Querystring:
        return Querystring()

    @property
    def custom_auth(self) -> httpx.Auth | None:
        return None

    @property
    def auth_headers(self) -> dict[str, str]:
        return {}

    @property
    def default_headers(self) -> dict[str, str | Omit]:
        return {
            "Accept": "application/json",
            "Content-Type": "application/json",
            "User-Agent": self.user_agent,
            **self.platform_headers(),
            **self.auth_headers,
            **self._custom_headers,
        }

    def _validate_headers(
        self,
        headers: Headers,  # noqa: ARG002
        custom_headers: Headers,  # noqa: ARG002
    ) -> None:
        """Validate the given default headers and custom headers.

        Does nothing by default.
        """
        return

    @property
    def user_agent(self) -> str:
        return f"{self.__class__.__name__}/Python {self._version}"

    @property
    def base_url(self) -> URL:
        return self._base_url

    @base_url.setter
    def base_url(self, url: URL | str) -> None:
        self._base_url = self._enforce_trailing_slash(url if isinstance(url, URL) else URL(url))

    def platform_headers(self) -> Dict[str, str]:
        return platform_headers(self._version)

    def _parse_retry_after_header(self, response_headers: Optional[httpx.Headers] = None) -> float | None:
        """Returns a float of the number of seconds (not milliseconds) to wait after retrying, or None if unspecified.

        About the Retry-After header: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After
        See also  https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After#syntax
        """
        if response_headers is None:
            return None

        # First, try the non-standard `retry-after-ms` header for milliseconds,
        # which is more precise than integer-seconds `retry-after`
        try:
            retry_ms_header = response_headers.get("retry-after-ms", None)
            return float(retry_ms_header) / 1000
        except (TypeError, ValueError):
            pass

        # Next, try parsing `retry-after` header as seconds (allowing nonstandard floats).
        retry_header = response_headers.get("retry-after")
        try:
            # note: the spec indicates that this should only ever be an integer
            # but if someone sends a float there's no reason for us to not respect it
            return float(retry_header)
        except (TypeError, ValueError):
            pass

        # Last, try parsing `retry-after` as a date.
        retry_date_tuple = email.utils.parsedate_tz(retry_header)
        if retry_date_tuple is None:
            return None

        retry_date = email.utils.mktime_tz(retry_date_tuple)
        return float(retry_date - time.time())

    def _calculate_retry_timeout(
        self,
        remaining_retries: int,
        options: FinalRequestOptions,
        response_headers: Optional[httpx.Headers] = None,
    ) -> float:
        max_retries = options.get_max_retries(self.max_retries)

        # If the API asks us to wait a certain amount of time (and it's a reasonable amount), just do what it says.
        retry_after = self._parse_retry_after_header(response_headers)
        if retry_after is not None and 0 < retry_after <= 60:
            return retry_after

        nb_retries = max_retries - remaining_retries

        # Apply exponential backoff, but not more than the max.
        sleep_seconds = min(INITIAL_RETRY_DELAY * pow(2.0, nb_retries), MAX_RETRY_DELAY)

        # Apply some jitter, plus-or-minus half a second.
        jitter = 1 - 0.25 * random()
        timeout = sleep_seconds * jitter
        return timeout if timeout >= 0 else 0

    def _should_retry(self, response: httpx.Response) -> bool:
        # Note: this is not a standard header
        should_retry_header = response.headers.get("x-should-retry")

        # If the server explicitly says whether or not to retry, obey.
        if should_retry_header == "true":
            log.debug("Retrying as header `x-should-retry` is set to `true`")
            return True
        if should_retry_header == "false":
            log.debug("Not retrying as header `x-should-retry` is set to `false`")
            return False

        # Retry on request timeouts.
        if response.status_code == 408:
            log.debug("Retrying due to status code %i", response.status_code)
            return True

        # Retry on lock timeouts.
        if response.status_code == 409:
            log.debug("Retrying due to status code %i", response.status_code)
            return True

        # Retry on rate limits.
        if response.status_code == 429:
            log.debug("Retrying due to status code %i", response.status_code)
            return True

        # Retry internal errors.
        if response.status_code >= 500:
            log.debug("Retrying due to status code %i", response.status_code)
            return True

        log.debug("Not retrying")
        return False

    def _idempotency_key(self) -> str:
        return f"stainless-python-retry-{uuid.uuid4()}"


class SyncHttpxClientWrapper(httpx.Client):
    def __del__(self) -> None:
        try:
            self.close()
        except Exception:
            pass


class SyncAPIClient(BaseClient[httpx.Client, Stream[Any]]):
    _client: httpx.Client
    _default_stream_cls: type[Stream[Any]] | None = None

    def __init__(
        self,
        *,
        version: str,
        base_url: str | URL,
        max_retries: int = DEFAULT_MAX_RETRIES,
        timeout: float | Timeout | None | NotGiven = NOT_GIVEN,
        transport: Transport | None = None,
        proxies: ProxiesTypes | None = None,
        limits: Limits | None = None,
        http_client: httpx.Client | None = None,
        custom_headers: Mapping[str, str] | None = None,
        custom_query: Mapping[str, object] | None = None,
        _strict_response_validation: bool,
    ) -> None:
        if limits is not None:
            warnings.warn(
                "The `connection_pool_limits` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `connection_pool_limits`")
        else:
            limits = DEFAULT_LIMITS

        if transport is not None:
            warnings.warn(
                "The `transport` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `transport`")

        if proxies is not None:
            warnings.warn(
                "The `proxies` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `proxies`")

        if not is_given(timeout):
            # if the user passed in a custom http client with a non-default
            # timeout set then we use that timeout.
            #
            # note: there is an edge case here where the user passes in a client
            # where they've explicitly set the timeout to match the default timeout
            # as this check is structural, meaning that we'll think they didn't
            # pass in a timeout and will ignore it
            if http_client and http_client.timeout != HTTPX_DEFAULT_TIMEOUT:
                timeout = http_client.timeout
            else:
                timeout = DEFAULT_TIMEOUT

        super().__init__(
            version=version,
            limits=limits,
            # cast to a valid type because mypy doesn't understand our type narrowing
            timeout=cast(Timeout, timeout),
            proxies=proxies,
            base_url=base_url,
            transport=transport,
            max_retries=max_retries,
            custom_query=custom_query,
            custom_headers=custom_headers,
            _strict_response_validation=_strict_response_validation,
        )
        self._client = http_client or SyncHttpxClientWrapper(
            base_url=base_url,
            # cast to a valid type because mypy doesn't understand our type narrowing
            timeout=cast(Timeout, timeout),
            proxies=proxies,
            transport=transport,
            limits=limits,
        )

    def is_closed(self) -> bool:
        return self._client.is_closed

    def close(self) -> None:
        """Close the underlying HTTPX client.

        The client will *not* be usable after this.
        """
        # If an error is thrown while constructing a client, self._client
        # may not be present
        if hasattr(self, "_client"):
            self._client.close()

    def __enter__(self: _T) -> _T:
        return self

    def __exit__(
        self,
        exc_type: type[BaseException] | None,
        exc: BaseException | None,
        exc_tb: TracebackType | None,
    ) -> None:
        self.close()

    def _prepare_options(
        self,
        options: FinalRequestOptions,  # noqa: ARG002
    ) -> None:
        """Hook for mutating the given options"""
        return None

    def _prepare_request(
        self,
        request: httpx.Request,  # noqa: ARG002
    ) -> None:
        """This method is used as a callback for mutating the `Request` object
        after it has been constructed.
        This is useful for cases where you want to add certain headers based off of
        the request properties, e.g. `url`, `method` etc.
        """
        return None

    @overload
    def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        remaining_retries: Optional[int] = None,
        *,
        stream: Literal[True],
        stream_cls: Type[_StreamT],
    ) -> _StreamT:
        ...

    @overload
    def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        remaining_retries: Optional[int] = None,
        *,
        stream: Literal[False] = False,
    ) -> ResponseT:
        ...

    @overload
    def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        remaining_retries: Optional[int] = None,
        *,
        stream: bool = False,
        stream_cls: Type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        ...

    def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        remaining_retries: Optional[int] = None,
        *,
        stream: bool = False,
        stream_cls: type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        return self._request(
            cast_to=cast_to,
            options=options,
            stream=stream,
            stream_cls=stream_cls,
            remaining_retries=remaining_retries,
        )

    def _request(
        self,
        *,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        remaining_retries: int | None,
        stream: bool,
        stream_cls: type[_StreamT] | None,
    ) -> ResponseT | _StreamT:
        cast_to = self._maybe_override_cast_to(cast_to, options)
        self._prepare_options(options)

        retries = self._remaining_retries(remaining_retries, options)
        request = self._build_request(options)
        self._prepare_request(request)

        kwargs: HttpxSendArgs = {}
        if self.custom_auth is not None:
            kwargs["auth"] = self.custom_auth

        try:
            response = self._client.send(
                request,
                stream=stream or self._should_stream_response_body(request=request),
                **kwargs,
            )
        except httpx.TimeoutException as err:
            log.debug("Encountered httpx.TimeoutException", exc_info=True)

            if retries > 0:
                return self._retry_request(
                    options,
                    cast_to,
                    retries,
                    stream=stream,
                    stream_cls=stream_cls,
                    response_headers=None,
                )

            log.debug("Raising timeout error")
            raise APITimeoutError(request=request) from err
        except Exception as err:
            log.debug("Encountered Exception", exc_info=True)

            if retries > 0:
                return self._retry_request(
                    options,
                    cast_to,
                    retries,
                    stream=stream,
                    stream_cls=stream_cls,
                    response_headers=None,
                )

            log.debug("Raising connection error")
            raise APIConnectionError(request=request) from err

        log.debug(
            'HTTP Request: %s %s "%i %s"', request.method, request.url, response.status_code, response.reason_phrase
        )

        try:
            response.raise_for_status()
        except httpx.HTTPStatusError as err:  # thrown on 4xx and 5xx status code
            log.debug("Encountered httpx.HTTPStatusError", exc_info=True)

            if retries > 0 and self._should_retry(err.response):
                err.response.close()
                return self._retry_request(
                    options,
                    cast_to,
                    retries,
                    err.response.headers,
                    stream=stream,
                    stream_cls=stream_cls,
                )

            # If the response is streamed then we need to explicitly read the response
            # to completion before attempting to access the response text.
            if not err.response.is_closed:
                err.response.read()

            log.debug("Re-raising status error")
            raise self._make_status_error_from_response(err.response) from None

        return self._process_response(
            cast_to=cast_to,
            options=options,
            response=response,
            stream=stream,
            stream_cls=stream_cls,
        )

    def _retry_request(
        self,
        options: FinalRequestOptions,
        cast_to: Type[ResponseT],
        remaining_retries: int,
        response_headers: httpx.Headers | None,
        *,
        stream: bool,
        stream_cls: type[_StreamT] | None,
    ) -> ResponseT | _StreamT:
        remaining = remaining_retries - 1
        if remaining == 1:
            log.debug("1 retry left")
        else:
            log.debug("%i retries left", remaining)

        timeout = self._calculate_retry_timeout(remaining, options, response_headers)
        log.info("Retrying request to %s in %f seconds", options.url, timeout)

        # In a synchronous context we are blocking the entire thread. Up to the library user to run the client in a
        # different thread if necessary.
        time.sleep(timeout)

        return self._request(
            options=options,
            cast_to=cast_to,
            remaining_retries=remaining,
            stream=stream,
            stream_cls=stream_cls,
        )

    def _process_response(
        self,
        *,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        response: httpx.Response,
        stream: bool,
        stream_cls: type[Stream[Any]] | type[AsyncStream[Any]] | None,
    ) -> ResponseT:
        if response.request.headers.get(RAW_RESPONSE_HEADER) == "true":
            return cast(
                ResponseT,
                LegacyAPIResponse(
                    raw=response,
                    client=self,
                    cast_to=cast_to,
                    stream=stream,
                    stream_cls=stream_cls,
                    options=options,
                ),
            )

        origin = get_origin(cast_to) or cast_to

        if inspect.isclass(origin) and issubclass(origin, BaseAPIResponse):
            if not issubclass(origin, APIResponse):
                raise TypeError(f"API Response types must subclass {APIResponse}; Received {origin}")

            response_cls = cast("type[BaseAPIResponse[Any]]", cast_to)
            return cast(
                ResponseT,
                response_cls(
                    raw=response,
                    client=self,
                    cast_to=extract_response_type(response_cls),
                    stream=stream,
                    stream_cls=stream_cls,
                    options=options,
                ),
            )

        if cast_to == httpx.Response:
            return cast(ResponseT, response)

        api_response = APIResponse(
            raw=response,
            client=self,
            cast_to=cast("type[ResponseT]", cast_to),  # pyright: ignore[reportUnnecessaryCast]
            stream=stream,
            stream_cls=stream_cls,
            options=options,
        )
        if bool(response.request.headers.get(RAW_RESPONSE_HEADER)):
            return cast(ResponseT, api_response)

        return api_response.parse()

    def _request_api_list(
        self,
        model: Type[object],
        page: Type[SyncPageT],
        options: FinalRequestOptions,
    ) -> SyncPageT:
        def _parser(resp: SyncPageT) -> SyncPageT:
            resp._set_private_attributes(
                client=self,
                model=model,
                options=options,
            )
            return resp

        options.post_parser = _parser

        return self.request(page, options, stream=False)

    @overload
    def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: Literal[False] = False,
    ) -> ResponseT:
        ...

    @overload
    def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: Literal[True],
        stream_cls: type[_StreamT],
    ) -> _StreamT:
        ...

    @overload
    def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: bool,
        stream_cls: type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        ...

    def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: bool = False,
        stream_cls: type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        opts = FinalRequestOptions.construct(method="get", url=path, **options)
        # cast is required because mypy complains about returning Any even though
        # it understands the type variables
        return cast(ResponseT, self.request(cast_to, opts, stream=stream, stream_cls=stream_cls))

    @overload
    def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
        files: RequestFiles | None = None,
        stream: Literal[False] = False,
    ) -> ResponseT:
        ...

    @overload
    def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
        files: RequestFiles | None = None,
        stream: Literal[True],
        stream_cls: type[_StreamT],
    ) -> _StreamT:
        ...

    @overload
    def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
        files: RequestFiles | None = None,
        stream: bool,
        stream_cls: type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        ...

    def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
        files: RequestFiles | None = None,
        stream: bool = False,
        stream_cls: type[_StreamT] | None = None,
    ) -> ResponseT | _StreamT:
        opts = FinalRequestOptions.construct(
            method="post", url=path, json_data=body, files=to_httpx_files(files), **options
        )
        return cast(ResponseT, self.request(cast_to, opts, stream=stream, stream_cls=stream_cls))

    def patch(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(method="patch", url=path, json_data=body, **options)
        return self.request(cast_to, opts)

    def put(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(
            method="put", url=path, json_data=body, files=to_httpx_files(files), **options
        )
        return self.request(cast_to, opts)

    def delete(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(method="delete", url=path, json_data=body, **options)
        return self.request(cast_to, opts)

    def get_api_list(
        self,
        path: str,
        *,
        model: Type[object],
        page: Type[SyncPageT],
        body: Body | None = None,
        options: RequestOptions = {},
        method: str = "get",
    ) -> SyncPageT:
        opts = FinalRequestOptions.construct(method=method, url=path, json_data=body, **options)
        return self._request_api_list(model, page, opts)


class AsyncHttpxClientWrapper(httpx.AsyncClient):
    def __del__(self) -> None:
        try:
            # TODO(someday): support non asyncio runtimes here
            asyncio.get_running_loop().create_task(self.aclose())
        except Exception:
            pass


class AsyncAPIClient(BaseClient[httpx.AsyncClient, AsyncStream[Any]]):
    _client: httpx.AsyncClient
    _default_stream_cls: type[AsyncStream[Any]] | None = None

    def __init__(
        self,
        *,
        version: str,
        base_url: str | URL,
        _strict_response_validation: bool,
        max_retries: int = DEFAULT_MAX_RETRIES,
        timeout: float | Timeout | None | NotGiven = NOT_GIVEN,
        transport: AsyncTransport | None = None,
        proxies: ProxiesTypes | None = None,
        limits: Limits | None = None,
        http_client: httpx.AsyncClient | None = None,
        custom_headers: Mapping[str, str] | None = None,
        custom_query: Mapping[str, object] | None = None,
    ) -> None:
        if limits is not None:
            warnings.warn(
                "The `connection_pool_limits` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `connection_pool_limits`")
        else:
            limits = DEFAULT_LIMITS

        if transport is not None:
            warnings.warn(
                "The `transport` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `transport`")

        if proxies is not None:
            warnings.warn(
                "The `proxies` argument is deprecated. The `http_client` argument should be passed instead",
                category=DeprecationWarning,
                stacklevel=3,
            )
            if http_client is not None:
                raise ValueError("The `http_client` argument is mutually exclusive with `proxies`")

        if not is_given(timeout):
            # if the user passed in a custom http client with a non-default
            # timeout set then we use that timeout.
            #
            # note: there is an edge case here where the user passes in a client
            # where they've explicitly set the timeout to match the default timeout
            # as this check is structural, meaning that we'll think they didn't
            # pass in a timeout and will ignore it
            if http_client and http_client.timeout != HTTPX_DEFAULT_TIMEOUT:
                timeout = http_client.timeout
            else:
                timeout = DEFAULT_TIMEOUT

        super().__init__(
            version=version,
            base_url=base_url,
            limits=limits,
            # cast to a valid type because mypy doesn't understand our type narrowing
            timeout=cast(Timeout, timeout),
            proxies=proxies,
            transport=transport,
            max_retries=max_retries,
            custom_query=custom_query,
            custom_headers=custom_headers,
            _strict_response_validation=_strict_response_validation,
        )
        self._client = http_client or AsyncHttpxClientWrapper(
            base_url=base_url,
            # cast to a valid type because mypy doesn't understand our type narrowing
            timeout=cast(Timeout, timeout),
            proxies=proxies,
            transport=transport,
            limits=limits,
        )

    def is_closed(self) -> bool:
        return self._client.is_closed

    async def close(self) -> None:
        """Close the underlying HTTPX client.

        The client will *not* be usable after this.
        """
        await self._client.aclose()

    async def __aenter__(self: _T) -> _T:
        return self

    async def __aexit__(
        self,
        exc_type: type[BaseException] | None,
        exc: BaseException | None,
        exc_tb: TracebackType | None,
    ) -> None:
        await self.close()

    async def _prepare_options(
        self,
        options: FinalRequestOptions,  # noqa: ARG002
    ) -> None:
        """Hook for mutating the given options"""
        return None

    async def _prepare_request(
        self,
        request: httpx.Request,  # noqa: ARG002
    ) -> None:
        """This method is used as a callback for mutating the `Request` object
        after it has been constructed.
        This is useful for cases where you want to add certain headers based off of
        the request properties, e.g. `url`, `method` etc.
        """
        return None

    @overload
    async def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        *,
        stream: Literal[False] = False,
        remaining_retries: Optional[int] = None,
    ) -> ResponseT:
        ...

    @overload
    async def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        *,
        stream: Literal[True],
        stream_cls: type[_AsyncStreamT],
        remaining_retries: Optional[int] = None,
    ) -> _AsyncStreamT:
        ...

    @overload
    async def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        *,
        stream: bool,
        stream_cls: type[_AsyncStreamT] | None = None,
        remaining_retries: Optional[int] = None,
    ) -> ResponseT | _AsyncStreamT:
        ...

    async def request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        *,
        stream: bool = False,
        stream_cls: type[_AsyncStreamT] | None = None,
        remaining_retries: Optional[int] = None,
    ) -> ResponseT | _AsyncStreamT:
        return await self._request(
            cast_to=cast_to,
            options=options,
            stream=stream,
            stream_cls=stream_cls,
            remaining_retries=remaining_retries,
        )

    async def _request(
        self,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        *,
        stream: bool,
        stream_cls: type[_AsyncStreamT] | None,
        remaining_retries: int | None,
    ) -> ResponseT | _AsyncStreamT:
        cast_to = self._maybe_override_cast_to(cast_to, options)
        await self._prepare_options(options)

        retries = self._remaining_retries(remaining_retries, options)
        request = self._build_request(options)
        await self._prepare_request(request)

        kwargs: HttpxSendArgs = {}
        if self.custom_auth is not None:
            kwargs["auth"] = self.custom_auth

        try:
            response = await self._client.send(
                request,
                stream=stream or self._should_stream_response_body(request=request),
                **kwargs,
            )
        except httpx.TimeoutException as err:
            log.debug("Encountered httpx.TimeoutException", exc_info=True)

            if retries > 0:
                return await self._retry_request(
                    options,
                    cast_to,
                    retries,
                    stream=stream,
                    stream_cls=stream_cls,
                    response_headers=None,
                )

            log.debug("Raising timeout error")
            raise APITimeoutError(request=request) from err
        except Exception as err:
            log.debug("Encountered Exception", exc_info=True)

            if retries > 0:
                return await self._retry_request(
                    options,
                    cast_to,
                    retries,
                    stream=stream,
                    stream_cls=stream_cls,
                    response_headers=None,
                )

            log.debug("Raising connection error")
            raise APIConnectionError(request=request) from err

        log.debug(
            'HTTP Request: %s %s "%i %s"', request.method, request.url, response.status_code, response.reason_phrase
        )

        try:
            response.raise_for_status()
        except httpx.HTTPStatusError as err:  # thrown on 4xx and 5xx status code
            log.debug("Encountered httpx.HTTPStatusError", exc_info=True)

            if retries > 0 and self._should_retry(err.response):
                await err.response.aclose()
                return await self._retry_request(
                    options,
                    cast_to,
                    retries,
                    err.response.headers,
                    stream=stream,
                    stream_cls=stream_cls,
                )

            # If the response is streamed then we need to explicitly read the response
            # to completion before attempting to access the response text.
            if not err.response.is_closed:
                await err.response.aread()

            log.debug("Re-raising status error")
            raise self._make_status_error_from_response(err.response) from None

        return await self._process_response(
            cast_to=cast_to,
            options=options,
            response=response,
            stream=stream,
            stream_cls=stream_cls,
        )

    async def _retry_request(
        self,
        options: FinalRequestOptions,
        cast_to: Type[ResponseT],
        remaining_retries: int,
        response_headers: httpx.Headers | None,
        *,
        stream: bool,
        stream_cls: type[_AsyncStreamT] | None,
    ) -> ResponseT | _AsyncStreamT:
        remaining = remaining_retries - 1
        if remaining == 1:
            log.debug("1 retry left")
        else:
            log.debug("%i retries left", remaining)

        timeout = self._calculate_retry_timeout(remaining, options, response_headers)
        log.info("Retrying request to %s in %f seconds", options.url, timeout)

        await anyio.sleep(timeout)

        return await self._request(
            options=options,
            cast_to=cast_to,
            remaining_retries=remaining,
            stream=stream,
            stream_cls=stream_cls,
        )

    async def _process_response(
        self,
        *,
        cast_to: Type[ResponseT],
        options: FinalRequestOptions,
        response: httpx.Response,
        stream: bool,
        stream_cls: type[Stream[Any]] | type[AsyncStream[Any]] | None,
    ) -> ResponseT:
        if response.request.headers.get(RAW_RESPONSE_HEADER) == "true":
            return cast(
                ResponseT,
                LegacyAPIResponse(
                    raw=response,
                    client=self,
                    cast_to=cast_to,
                    stream=stream,
                    stream_cls=stream_cls,
                    options=options,
                ),
            )

        origin = get_origin(cast_to) or cast_to

        if inspect.isclass(origin) and issubclass(origin, BaseAPIResponse):
            if not issubclass(origin, AsyncAPIResponse):
                raise TypeError(f"API Response types must subclass {AsyncAPIResponse}; Received {origin}")

            response_cls = cast("type[BaseAPIResponse[Any]]", cast_to)
            return cast(
                "ResponseT",
                response_cls(
                    raw=response,
                    client=self,
                    cast_to=extract_response_type(response_cls),
                    stream=stream,
                    stream_cls=stream_cls,
                    options=options,
                ),
            )

        if cast_to == httpx.Response:
            return cast(ResponseT, response)

        api_response = AsyncAPIResponse(
            raw=response,
            client=self,
            cast_to=cast("type[ResponseT]", cast_to),  # pyright: ignore[reportUnnecessaryCast]
            stream=stream,
            stream_cls=stream_cls,
            options=options,
        )
        if bool(response.request.headers.get(RAW_RESPONSE_HEADER)):
            return cast(ResponseT, api_response)

        return await api_response.parse()

    def _request_api_list(
        self,
        model: Type[_T],
        page: Type[AsyncPageT],
        options: FinalRequestOptions,
    ) -> AsyncPaginator[_T, AsyncPageT]:
        return AsyncPaginator(client=self, options=options, page_cls=page, model=model)

    @overload
    async def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: Literal[False] = False,
    ) -> ResponseT:
        ...

    @overload
    async def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: Literal[True],
        stream_cls: type[_AsyncStreamT],
    ) -> _AsyncStreamT:
        ...

    @overload
    async def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: bool,
        stream_cls: type[_AsyncStreamT] | None = None,
    ) -> ResponseT | _AsyncStreamT:
        ...

    async def get(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        options: RequestOptions = {},
        stream: bool = False,
        stream_cls: type[_AsyncStreamT] | None = None,
    ) -> ResponseT | _AsyncStreamT:
        opts = FinalRequestOptions.construct(method="get", url=path, **options)
        return await self.request(cast_to, opts, stream=stream, stream_cls=stream_cls)

    @overload
    async def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
        stream: Literal[False] = False,
    ) -> ResponseT:
        ...

    @overload
    async def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
        stream: Literal[True],
        stream_cls: type[_AsyncStreamT],
    ) -> _AsyncStreamT:
        ...

    @overload
    async def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
        stream: bool,
        stream_cls: type[_AsyncStreamT] | None = None,
    ) -> ResponseT | _AsyncStreamT:
        ...

    async def post(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
        stream: bool = False,
        stream_cls: type[_AsyncStreamT] | None = None,
    ) -> ResponseT | _AsyncStreamT:
        opts = FinalRequestOptions.construct(
            method="post", url=path, json_data=body, files=await async_to_httpx_files(files), **options
        )
        return await self.request(cast_to, opts, stream=stream, stream_cls=stream_cls)

    async def patch(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(method="patch", url=path, json_data=body, **options)
        return await self.request(cast_to, opts)

    async def put(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        files: RequestFiles | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(
            method="put", url=path, json_data=body, files=await async_to_httpx_files(files), **options
        )
        return await self.request(cast_to, opts)

    async def delete(
        self,
        path: str,
        *,
        cast_to: Type[ResponseT],
        body: Body | None = None,
        options: RequestOptions = {},
    ) -> ResponseT:
        opts = FinalRequestOptions.construct(method="delete", url=path, json_data=body, **options)
        return await self.request(cast_to, opts)

    def get_api_list(
        self,
        path: str,
        *,
        model: Type[_T],
        page: Type[AsyncPageT],
        body: Body | None = None,
        options: RequestOptions = {},
        method: str = "get",
    ) -> AsyncPaginator[_T, AsyncPageT]:
        opts = FinalRequestOptions.construct(method=method, url=path, json_data=body, **options)
        return self._request_api_list(model, page, opts)


def make_request_options(
    *,
    query: Query | None = None,
    extra_headers: Headers | None = None,
    extra_query: Query | None = None,
    extra_body: Body | None = None,
    idempotency_key: str | None = None,
    timeout: float | httpx.Timeout | None | NotGiven = NOT_GIVEN,
    post_parser: PostParser | NotGiven = NOT_GIVEN,
) -> RequestOptions:
    """Create a dict of type RequestOptions without keys of NotGiven values."""
    options: RequestOptions = {}
    if extra_headers is not None:
        options["headers"] = extra_headers

    if extra_body is not None:
        options["extra_json"] = cast(AnyMapping, extra_body)

    if query is not None:
        options["params"] = query

    if extra_query is not None:
        options["params"] = {**options.get("params", {}), **extra_query}

    if not isinstance(timeout, NotGiven):
        options["timeout"] = timeout

    if idempotency_key is not None:
        options["idempotency_key"] = idempotency_key

    if is_given(post_parser):
        # internal
        options["post_parser"] = post_parser  # type: ignore

    return options


class OtherPlatform:
    def __init__(self, name: str) -> None:
        self.name = name

    @override
    def __str__(self) -> str:
        return f"Other:{self.name}"


Platform = Union[
    OtherPlatform,
    Literal[
        "MacOS",
        "Linux",
        "Windows",
        "FreeBSD",
        "OpenBSD",
        "iOS",
        "Android",
        "Unknown",
    ],
]


def get_platform() -> Platform:
    system = platform.system().lower()
    platform_name = platform.platform().lower()
    if "iphone" in platform_name or "ipad" in platform_name:
        # Tested using Python3IDE on an iPhone 11 and Pythonista on an iPad 7
        # system is Darwin and platform_name is a string like:
        # - Darwin-21.6.0-iPhone12,1-64bit
        # - Darwin-21.6.0-iPad7,11-64bit
        return "iOS"

    if system == "darwin":
        return "MacOS"

    if system == "windows":
        return "Windows"

    if "android" in platform_name:
        # Tested using Pydroid 3
        # system is Linux and platform_name is a string like 'Linux-5.10.81-android12-9-00001-geba40aecb3b7-ab8534902-aarch64-with-libc'
        return "Android"

    if system == "linux":
        # https://distro.readthedocs.io/en/latest/#distro.id
        distro_id = distro.id()
        if distro_id == "freebsd":
            return "FreeBSD"

        if distro_id == "openbsd":
            return "OpenBSD"

        return "Linux"

    if platform_name:
        return OtherPlatform(platform_name)

    return "Unknown"


@lru_cache(maxsize=None)
def platform_headers(version: str) -> Dict[str, str]:
    return {
        "X-Stainless-Lang": "python",
        "X-Stainless-Package-Version": version,
        "X-Stainless-OS": str(get_platform()),
        "X-Stainless-Arch": str(get_architecture()),
        "X-Stainless-Runtime": platform.python_implementation(),
        "X-Stainless-Runtime-Version": platform.python_version(),
    }


class OtherArch:
    def __init__(self, name: str) -> None:
        self.name = name

    @override
    def __str__(self) -> str:
        return f"other:{self.name}"


Arch = Union[OtherArch, Literal["x32", "x64", "arm", "arm64", "unknown"]]


def get_architecture() -> Arch:
    python_bitness, _ = platform.architecture()
    machine = platform.machine().lower()
    if machine in ("arm64", "aarch64"):
        return "arm64"

    # TODO: untested
    if machine == "arm":
        return "arm"

    if machine == "x86_64":
        return "x64"

    # TODO: untested
    if python_bitness == "32bit":
        return "x32"

    if machine:
        return OtherArch(machine)

    return "unknown"


def _merge_mappings(
    obj1: Mapping[_T_co, Union[_T, Omit]],
    obj2: Mapping[_T_co, Union[_T, Omit]],
) -> Dict[_T_co, _T]:
    """Merge two mappings of the same type, removing any values that are instances of `Omit`.

    In cases with duplicate keys the second mapping takes precedence.
    """
    merged = {**obj1, **obj2}
    return {key: value for key, value in merged.items() if not isinstance(value, Omit)}