returning a stream event without "data:"

[syberkitten]

Hi

It seems like the "data:" prefix is always returned when a stream text fragment is returned to client.

In most cases this can be fixed on the client but it would be better to be able to specify if you really need this prefix or just return that raw data as it is.

code is in sse.py:

    if self.data is not None:
        for chunk in self.LINE_SEP_EXPR.split(str(self.data)):
            buffer.write(f"data: {chunk}")
            buffer.write(self._sep)

I can do a PR/MR if makes it easier, simplest is to add to the yield that is going to the ServerSentEvent:

for example: yield dict(data={ "text": "my text", }, data_prefix="")

[syberkitten]

class ServerSentEvent: def init( self, data: Optional[Any] = None, *, event: Optional[str] = None, id: Optional[int] = None, retry: Optional[int] = None, comment: Optional[str] = None, sep: Optional[str] = None, data_prefix="data: ", )

        if self.data is not None:
          for chunk in self.LINE_SEP_EXPR.split(str(self.data)):
              buffer.write(f"{self.data_prefix}{chunk}")
              buffer.write(self._sep)

[paxcodes]

Correct me if I'm wrong but it seems from the reading of the SSE spec (https://html.spec.whatwg.org/multipage/server-sent-events.html#the-eventsource-interface), the "data: " prefix is required if you want to send data to be processed by clients. Otherwise, the line will/should be ignored by clients following the spec.   

18 Jun 2023, 02:21 by @.***:

Hi

It seems like the "data:" prefix is always returned when a stream text fragment is returned to client.

In most cases this can be fixed on the client but it would be better to be able to specify if you really need this prefix or just return that raw data as it is.

code is in sse.py:

if self.data is not None:        for chunk in self.LINE_SEP_EXPR.split(str(self.data)):            buffer.write(f"data: {chunk}")            buffer.write(self._sep)

I can do a PR/MR if makes it easier, simplest is to add to the yield that is going to the ServerSentEvent:

for example: yield dict(data={ "text": "my text", }, data_prefix="")

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[sysid]

My understanding concurs with @paxcodes . Please correct my understanding by pointing to the respective spec or an authoritative example.

[syberkitten]

hi @sysid and @paxcodes thanks for pointing my attention to this, closing the merge request.