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Re: Multiple header fields with the same field name - unwritten assumption about quoted commas in values?

Piotr Dobrogost <p@ietf.dobrogost.net> Tue, 15 January 2013 11:50 UTC

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From: Piotr Dobrogost <p@ietf.dobrogost.net>
Date: Tue, 15 Jan 2013 12:47:29 +0100
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Subject: Re: Multiple header fields with the same field name - unwritten assumption about quoted commas in values?
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To summarize, from the point of view of http client library (see
https://github.com/kennethreitz/requests/issues/741):

- The safe approach is to not merge any header fields with the same field name.
- If merging, merge only those fields which are known to be safe to
merge ie. those, which can be parsed after merging. Also, if the top
most production in BNF specyfing field's value is #(values) it does
NOT mean the field is safe for merging although this seems to be
implied by the statement in the spec starting with "Multiple header
fields with the same field name MUST NOT be sent (...)"


Regards,
Piotr

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