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author | Loïc Hoguin <[email protected]> | 2016-11-05 14:17:30 +0200 |
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committer | Loïc Hoguin <[email protected]> | 2016-11-05 14:17:30 +0200 |
commit | faca7866ed1c59cd41e11fcfc5a9f95378380497 (patch) | |
tree | 7e33284b3426083154b7a1d52ae5db8996212739 /doc/src/manual/cowboy_req.header.asciidoc | |
parent | 8fe700f341d324c44f6c5f196f8c699c85ee6d78 (diff) | |
download | cowboy-faca7866ed1c59cd41e11fcfc5a9f95378380497.tar.gz cowboy-faca7866ed1c59cd41e11fcfc5a9f95378380497.tar.bz2 cowboy-faca7866ed1c59cd41e11fcfc5a9f95378380497.zip |
Partially update manual for the cowboy_req
Only the access functions have been modified so far.
Diffstat (limited to 'doc/src/manual/cowboy_req.header.asciidoc')
-rw-r--r-- | doc/src/manual/cowboy_req.header.asciidoc | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/doc/src/manual/cowboy_req.header.asciidoc b/doc/src/manual/cowboy_req.header.asciidoc new file mode 100644 index 0000000..e16b902 --- /dev/null +++ b/doc/src/manual/cowboy_req.header.asciidoc @@ -0,0 +1,74 @@ += cowboy_req:header(3) + +== Name + +cowboy_req:header - HTTP header + +== Description + +[source,erlang] +---- +header(Name :: binary(), Req) -> header(Name, Req, undefined) +header(Name :: binary(), Req, Default) -> binary() | Default + +Req :: cowboy_req:req() +---- + +Return the value for the given HTTP header. + +The header name must be given as a lowercase binary string. +While header names are case insensitive, Cowboy requires them +to be given as lowercase to function properly. + +Headers can also be obtained using pattern matching: + +[source,erlang] +---- +#{headers := #{Name := Value}} = Req. +---- + +Note that this snippet will crash if the header is missing. + +== Arguments + +Name:: + +Desired HTTP header name as a binary string. + +Req:: + +The Req object. + +Default:: + +Default value returned when the header is missing. + +== Return value + +The header value is returned as a binary string. When the +header is missing, the default argument is returned. + +== Changelog + +* *2.0*: Only the header value is returned, it is no longer wrapped in a tuple. +* *1.0*: Function introduced. + +== Examples + +.Get the accept header +[source,erlang] +---- +Accept = cowboy_req:header(<<"accept">>, Req). +---- + +.Get the content-length header with a default value +[source,erlang] +---- +Length = cowboy_req:header(<<"content-length">>, Req, <<"0">>). +---- + +== See also + +link:man:cowboy_req(3)[cowboy_req(3)], +link:man:cowboy_req:headers(3)[cowboy_req:headers(3)], +link:man:cowboy_req:parse_header(3)[cowboy_req:parse_header(3)] |