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https://issues.apache.org/jira/browse/MESOS-9189?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16596183#comment-16596183
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Alexander Rukletsov commented on MESOS-9189:
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I'm not sure I understand how the change is supposed to help. {{'Connection:
close'}} set by a server is an indicator for the client to close the connection
_after_ receiveng the complete response. AFAIK, we don't ever complete the
streaming response in Mesos and there is no way for Mesos to somehow
understand that an end client might not be interested in the stream any more
and send an empty chunk. From a middleman's point of view the actual value of
the {{'Connection'}} header is only interesting _after_ the response is
completed, i.e., an empty chunk has been received, which, IIRC, never happens
in our case.
Is the hope here is that some middlemen peek into the {{'Connection'}} header
and based on it decide whether to close the connection themselves when their
client disconnects even though the response might not be completed?
> Include 'Connection: close' header in streaming API responses.
> --------------------------------------------------------------
>
> Key: MESOS-9189
> URL: https://issues.apache.org/jira/browse/MESOS-9189
> Project: Mesos
> Issue Type: Improvement
> Components: HTTP API
> Reporter: Benjamin Mahler
> Assignee: Benjamin Mahler
> Priority: Major
>
> We've seen some HTTP intermediaries (e.g. ELB) decide to re-use connections
> to mesos as an optimization to avoid re-connection overhead. As a result,
> when the end-client of the streaming API disconnects from the intermediary,
> the intermediary leaves the connection to mesos open in an attempt to re-use
> the connection for another request once the response completes. Mesos then
> thinks that the subscriber never disconnected and the intermediary happily
> continues to read the streaming events even though there's no end-client.
> To help indicate to intermediaries that the connection SHOULD NOT be re-used,
> we can set the 'Connection: close' header for streaming API responses. It may
> not be respected (since the language seems to be SHOULD NOT), but some
> intermediaries may respect it and close the connection if the end-client
> disconnects.
> Note that libprocess' http server currently doesn't close the the connection
> based on a handler setting this header, but it doesn't matter here since the
> streaming API responses are infinite.
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