= cowboy_req:set_resp_cookie(3)
== Name
cowboy_req:set_resp_cookie - Set a cookie
== Description
[source,erlang]
----
set_resp_cookie(Name, Value, Req :: cowboy_req:req())
-> set_resp_cookie(Name, Value, Req, #{})
set_resp_cookie(Name, Value, Req :: cowboy_req:req(), Opts)
-> Req
Name :: binary() %% case sensitive
Value :: iodata() %% case sensitive
Opts :: cow_cookie:cookie_opts()
----
Set a cookie to be sent with the response.
Note that cookie names are case sensitive.
== Arguments
Name::
Cookie name.
Value::
Cookie value.
Req::
The Req object.
Opts::
Cookie options.
== Return value
A new Req object is returned.
The returned Req object must be used from that point onward,
otherwise the cookie will not be sent in the response.
== Changelog
* *2.0*: `set_resp_cookie/3` introduced as an alias to `set_resp_cookie/4` with no options.
* *2.0*: The first argument type is now `binary()` instead of `iodata()`.
* *1.0*: Function introduced.
== Examples
.Set a session cookie
[source,erlang]
----
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0).
----
.Set a cookie with an expiration time
[source,erlang]
----
Req = cowboy_req:set_resp_cookie(<<"lang">>, <<"fr-FR">>,
Req0, #{max_age => 3600}).
----
.Delete a cookie
[source,erlang]
----
Req = cowboy_req:set_resp_cookie(<<"sessionid">>, <<>>,
Req0, #{max_age => 0}).
----
.Set a cookie for a specific domain and path
[source,erlang]
----
Req = cowboy_req:set_resp_cookie(<<"inaccount">>, <<"1">>,
Req0, #{domain => "my.example.org", path => "/account"}).
----
.Restrict a cookie to HTTPS
[source,erlang]
----
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID,
Req0, #{secure => true}).
----
.Restrict a cookie to HTTP
[source,erlang]
----
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID,
Req0, #{http_only => true}).
----
== See also
link:man:cowboy_req(3)[cowboy_req(3)],
link:man:cowboy_req:set_resp_header(3)[cowboy_req:set_resp_header(3)],
link:man:cowboy_req:set_resp_headers(3)[cowboy_req:set_resp_headers(3)],
link:man:cowboy_req:reply(3)[cowboy_req:reply(3)],
link:man:cowboy_req:stream_reply(3)[cowboy_req:stream_reply(3)]
