Initial implementation of the gun_cookies cookie store

1 files changed, 121 insertions, 0 deletions

diff --git a/src/gun_cookies_list.erl b/src/gun_cookies_list.erl
new file mode 100644
index 0000000..2b4a666
--- /dev/null
+++ b/src/gun_cookies_list.erl
@@ -0,0 +1,121 @@
+%% Copyright (c) 2020, Loïc Hoguin <[email protected]>
+%%
+%% Permission to use, copy, modify, and/or distribute this software for any
+%% purpose with or without fee is hereby granted, provided that the above
+%% copyright notice and this permission notice appear in all copies.
+%%
+%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+%% A reference cookie store implemented as a list of cookies.
+%% This cookie store cannot be shared between connections.
+-module(gun_cookies_list).
+
+-export([init/0]).
+-export([query/2]).
+-export([set_cookie_secure_match/2]).
+-export([set_cookie_take_exact_match/2]).
+-export([store/2]).
+
+-type state() :: #{
+	cookies := [gun_cookies:cookie()]
+	%% @todo Options would go here.
+}.
+
+-spec init() -> {?MODULE, state()}.
+init() ->
+	{?MODULE, #{cookies => []}}.
+
+-spec query(State, uri_string:uri_map())
+	-> {ok, [{binary(), binary()}], State}
+	when State::state().
+query(State=#{cookies := Cookies}, URI) ->
+	CurrentTime = erlang:universaltime(),
+	query(State, URI, Cookies, CurrentTime, [], []).
+
+query(State, _, [], _, CookieList, Cookies) ->
+	{ok, CookieList, State#{cookies => Cookies}};
+query(State, URI=#{scheme := Scheme, host := Host, path := Path},
+		[Cookie|Tail], CurrentTime, CookieList, Acc) ->
+	%% @todo This is probably not correct, says "canonicalized request-host"
+	%% and currently doesn't include the port number, it probably should?
+	Match0 = case Cookie of
+		#{host_only := true, domain := Host} ->
+			true;
+		#{host_only := false, domain := Domain} ->
+			gun_cookies:domain_match(Host, Domain);
+		_ ->
+			false
+	end,
+	Match1 = Match0 andalso
+		gun_cookies:path_match(Path, maps:get(path, Cookie)),
+	Match = Match1 andalso
+		case {Cookie, Scheme} of
+			{#{secure_only := true}, <<"https">>} -> true;
+			{#{secure_only := false}, _} -> true;
+			_ -> false
+		end,
+	%% @todo This is where we would check the http_only flag should
+	%% we want to implement a non-HTTP interface.
+	%% @todo This is where we would check for same-site/cross-site.
+	case Match of
+		true ->
+			UpdatedCookie = Cookie#{last_access_time => CurrentTime},
+			query(State, URI, Tail, CurrentTime,
+				[UpdatedCookie|CookieList],
+				[UpdatedCookie|Acc]);
+		false ->
+			query(State, URI, Tail, CurrentTime, CookieList, [Cookie|Acc])
+	end.
+
+-spec set_cookie_secure_match(state(), #{
+	name := binary(),
+%	secure_only := true,
+	domain := binary(),
+	path := binary()
+}) -> match | nomatch.
+set_cookie_secure_match(#{cookies := Cookies},
+		#{name := Name, domain := Domain, path := Path}) ->
+	Result = [Cookie || Cookie=#{name := CookieName, secure_only := true} <- Cookies,
+		CookieName =:= Name,
+		gun_cookies:domain_match(Domain, maps:get(domain, Cookie))
+			orelse gun_cookies:domain_match(maps:get(domain, Cookie), Domain),
+		gun_cookies:path_match(Path, maps:get(path, Cookie))],
+	case Result of
+		[] -> nomatch;
+		_ -> match
+	end.
+
+-spec set_cookie_take_exact_match(State, #{
+	name := binary(),
+	domain := binary(),
+	host_only := boolean(),
+	path := binary()
+}) -> {ok, gun_cookies:cookie(), State} | error when State::state().
+set_cookie_take_exact_match(State=#{cookies := Cookies0}, Match) ->
+	Result = [Cookie || Cookie <- Cookies0,
+		Match =:= maps:with([name, domain, host_only, path], Cookie)],
+	Cookies = [Cookie || Cookie <- Cookies0,
+		Match =/= maps:with([name, domain, host_only, path], Cookie)],
+	case Result of
+		[] -> error;
+		[Cookie] -> {ok, Cookie, State#{cookies => Cookies}}
+	end.
+
+-spec store(State, gun_cookies:cookie())
+	-> {ok, State} | {error, any()}
+	when State::state().
+store(State=#{cookies := Cookies}, NewCookie=#{expiry_time := ExpiryTime}) ->
+	CurrentTime = erlang:universaltime(),
+	if
+		%% Do not store cookies with an expiry time in the past.
+		ExpiryTime =/= infinity, CurrentTime >= ExpiryTime ->
+			{ok, State};
+		true ->
+			{ok, State#{cookies => [NewCookie|Cookies]}}
+	end.