cowboy_req:set_resp_headers - Set several response headers


set_resp_headers(Headers, Req :: cowboy_req:req())
    -> Req

Headers :: cowboy:http_headers()

Set several headers to be sent with the response.

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.

Cowboy does not allow duplicate header names. Headers set by this function may be overwritten by those set from the reply functions. Likewise, headers set by this function may overwrite headers that were set previously.

Use cowboy_req:set_resp_cookie(3) instead of this function to set cookies.



Headers as a map with keys being lowercase binary strings, and values as binary strings.


The Req object.

Return value

A new Req object is returned.

The returned Req object must be used from that point onward, otherwise the headers will not be sent in the response.


  • 2.0: Function introduced.


Set several response headers
Req = cowboy_req:set_resp_headers(#{
    <<"content-type">>     => <<"text/html">>,
    <<"content-encoding">> => <<"gzip">>
}, Req0).

See also

cowboy_req(3), cowboy_req:set_resp_cookie(3), cowboy_req:set_resp_header(3), cowboy_req:has_resp_header(3), cowboy_req:resp_header(3), cowboy_req:resp_headers(3), cowboy_req:delete_resp_header(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

Cowboy 2.7 Function Reference


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