from contextlib import asynccontextmanager, contextmanager
from typing import Any, AsyncIterator, Iterator
import httpx
from ._decoders import SSEDecoder
from ._exceptions import SSEError
from ._models import ServerSentEvent
class EventSource:
def __init__(self, response: httpx.Response) -> None:
self._response = response
def _check_content_type(self) -> None:
content_type = self._response.headers.get("content-type", "").partition(";")[0]
if "text/event-stream" not in content_type:
raise SSEError(
"Expected response header Content-Type to contain 'text/event-stream', "
f"got {content_type!r}"
)
@property
def response(self) -> httpx.Response:
return self._response
def iter_sse(self) -> Iterator[ServerSentEvent]:
self._check_content_type()
decoder = SSEDecoder()
for line in self._response.iter_lines():
line = line.rstrip("\n")
sse = decoder.decode(line)
if sse is not None:
yield sse
async def aiter_sse(self) -> AsyncIterator[ServerSentEvent]:
self._check_content_type()
decoder = SSEDecoder()
async for line in self._response.aiter_lines():
line = line.rstrip("\n")
sse = decoder.decode(line)
if sse is not None:
yield sse
@contextmanager
def connect_sse(
client: httpx.Client, method: str, url: str, **kwargs: Any
) -> Iterator[EventSource]:
headers = kwargs.pop("headers", {})
headers["Accept"] = "text/event-stream"
headers["Cache-Control"] = "no-store"
with client.stream(method, url, headers=headers, **kwargs) as response:
yield EventSource(response)
@asynccontextmanager
async def aconnect_sse(
client: httpx.AsyncClient,
method: str,
url: str,
**kwargs: Any,
) -> AsyncIterator[EventSource]:
headers = kwargs.pop("headers", {})
headers["Accept"] = "text/event-stream"
headers["Cache-Control"] = "no-store"
async with client.stream(method, url, headers=headers, **kwargs) as response:
yield EventSource(response)