hakuzaru/src/hz_fetcher.erl
2025-10-14 10:48:20 +09:00

243 lines
8.9 KiB
Erlang

-module(hz_fetcher).
-vsn("0.6.3").
-author("Craig Everett <ceverett@tsuriai.jp>").
-copyright("Craig Everett <ceverett@tsuriai.jp>").
-license("MIT").
-export([connect/4, slowly_connect/4]).
connect(Node = {Host, Port}, Request, From, Timeout) ->
Timer = erlang:send_after(Timeout, self(), timeout),
Options = [{mode, binary}, {nodelay, true}, {active, once}],
case gen_tcp:connect(Host, Port, Options, 3000) of
{ok, Sock} -> do(Request, Sock, Node, From, Timer);
Error -> gen_server:reply(From, Error)
end.
do(Request, Sock, Node, From, Timer) ->
Formed = unicode:characters_to_list(form(Request, Node)),
case gen_tcp:send(Sock, Formed) of
ok -> await(Sock, From, Timer);
Error -> gen_server:reply(From, Error)
end.
await(Sock, From, Timer) ->
receive
{tcp, Sock, Bin} ->
parse(Bin, Sock, From, Timer);
{tcp_closed, Sock} ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
gen_server:reply(From, {error, enotconn});
timeout ->
gen_server:reply(From, {error, timeout})
after 120000 ->
gen_server:reply(From, {error, timeout})
end.
form({get, Path}, Node) ->
["GET ", Path, " HTTP/1.1\r\n",
"Host: ", host_string(Node), "\r\n",
"User-Agent: Kanou/0.1.0\r\n",
"Accept: */*\r\n\r\n"];
form({post, Path, Payload}, Node) ->
ByteSize = integer_to_list(byte_size(Payload)),
["POST ", Path, " HTTP/1.1\r\n",
"Host: ", host_string(Node), "\r\n",
"Content-Type: application/json\r\n",
"Content-Length: ", ByteSize, "\r\n",
"User-Agent: Kanou/0.1.0\r\n",
"Accept: */*\r\n\r\n",
Payload].
host_string({Address, Port}) when is_list(Address) ->
PortS = integer_to_list(Port),
[Address, ":", PortS];
host_string({Address, Port}) when is_atom(Address) ->
AddressS = atom_to_list(Address),
PortS = integer_to_list(Port),
[AddressS, ":", PortS];
host_string({Address, Port}) ->
AddressS = inet:ntoa(Address),
PortS = integer_to_list(Port),
[AddressS, ":", PortS].
parse(Received, Sock, From, Timer) ->
case Received of
<<"HTTP/1.1 200 OK\r\n", Tail/binary>> ->
parse2(200, Tail, Sock, From, Timer);
<<"HTTP/1.1 400 Bad Request\r\n", Tail/binary>> ->
parse2(400, Tail, Sock, From, Timer);
<<"HTTP/1.1 404 Not Found\r\n", Tail/binary>> ->
parse2(404, Tail, Sock, From, Timer);
<<"HTTP/1.1 500 Internal Server Error\r\n", Tail/binary>> ->
parse2(500, Tail, Sock, From, Timer);
_ ->
ok = zx_net:disconnect(Sock),
ok = erlang:cancel_timer(Timer, [{async, true}]),
gen_server:reply(From, {error, {received, Received}})
end.
parse2(Code, Received, Sock, From, Timer) ->
case read_headers(Sock, Received) of
{ok, Headers, Rest} -> consume(Code, Rest, Headers, Sock, From, Timer);
Error -> gen_server:reply(From, Error)
end.
consume(Code, Rest, Headers, Sock, From, Timer) ->
case maps:find(<<"content-length">>, Headers) of
error ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
gen_server:reply(From, {error, {headers, Headers}});
{ok, <<"0">>} ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
Result = case Code =:= 200 of true -> ok; false -> {error, Code} end,
gen_server:reply(From, Result);
{ok, Size} ->
try
Length = binary_to_integer(Size),
consume2(Length, Rest, Sock, From, Timer)
catch
error:badarg ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
gen_server:reply(From, {error, {headers, Headers}})
end
end.
consume2(Length, Received, Sock, From, Timer) ->
Size = byte_size(Received),
if
Size == Length ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
ok = zx_net:disconnect(Sock),
Result = zj:decode(Received),
gen_server:reply(From, Result);
Size < Length ->
consume3(Length, Received, Sock, From, Timer);
Size > Length ->
ok = erlang:cancel_timer(Timer, [{async, true}]),
gen_server:reply(From, {error, bad_length})
end.
consume3(Length, Received, Sock, From, Timer) ->
ok = inet:setopts(Sock, [{active, once}]),
receive
{tcp, Sock, Bin} ->
consume2(Length, <<Received/binary, Bin/binary>>, Sock, From, Timer);
timeout ->
gen_server:reply(From, {error, {timeout, Received}})
end.
read_headers(Socket, <<"\r">>) ->
ok = inet:setopts(Socket, [{active, once}]),
receive
{tcp, Socket, Bin} -> read_headers(Socket, <<"\r", Bin/binary>>);
timeout -> {error, timeout}
after 120000 -> {error, timeout}
end;
read_headers(_, <<"\r\n", Received/binary>>) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers};
read_headers(Socket, Received) ->
read_hkey(Socket, Received, <<>>, #{}).
read_hkey(Socket, <<Char, Rest/binary>>, Acc, Headers)
when $A =< Char, Char =< $Z ->
read_hkey(Socket, Rest, <<Acc/binary, (Char + 32)>>, Headers);
read_hkey(Socket, <<Char, Rest/binary>>, Acc, Headers)
when 32 =< Char, Char =< 57;
59 =< Char, Char =< 126 ->
read_hkey(Socket, Rest, <<Acc/binary, Char>>, Headers);
read_hkey(Socket, <<":", Rest/binary>>, Key, Headers) ->
skip_hblanks(Socket, Rest, Key, Headers);
read_hkey(_, <<"\r\n", Rest/binary>>, <<>>, Headers) ->
{ok, Headers, Rest};
read_hkey(Socket, <<>>, Acc, Headers) ->
ok = inet:setopts(Socket, [{active, once}]),
receive
{tcp, Socket, Bin} -> read_hkey(Socket, Bin, Acc, Headers);
timeout -> {error, timeout}
after 120000 -> {error, timeout}
end;
read_hkey(_, Received, _, _) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers}.
skip_hblanks(Socket, <<" ", Rest/binary>>, Key, Headers) ->
skip_hblanks(Socket, Rest, Key, Headers);
skip_hblanks(Socket, <<>>, Key, Headers) ->
ok = inet:setopts(Socket, [{active, once}]),
receive
{tcp, Socket, Bin} -> skip_hblanks(Socket, Bin, Key, Headers);
timeout -> {error, timeout}
after 120000 -> {error, timeout}
end;
skip_hblanks(_, Received = <<"\r", _/binary>>, _, _) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers};
skip_hblanks(_, Received = <<"\n", _/binary>>, _, _) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers};
skip_hblanks(Socket, Rest, Key, Headers) ->
read_hval(Socket, Rest, <<>>, Key, Headers).
read_hval(_, Received = <<"\r\n", _/binary>>, <<>>, _, _) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers};
read_hval(Socket, <<"\r\n", Rest/binary>>, Val, Key, Headers) ->
read_hkey(Socket, Rest, <<>>, maps:put(Key, Val, Headers));
read_hval(Socket, <<Char, Rest/binary>>, Acc, Key, Headers)
when 32 =< Char, Char =< 126 ->
read_hval(Socket, Rest, <<Acc/binary, Char>>, Key, Headers);
read_hval(Socket, <<>>, Val, Key, Headers) ->
ok = inet:setopts(Socket, [{active, once}]),
receive
{tcp, Socket, Bin} -> read_hval(Socket, Bin, Val, Key, Headers);
timeout -> {error, timeout}
after 120000 -> {error, timeout}
end;
read_hval(_, Received, _, _, _) ->
log(info, "~p Headers died at: ~p", [?LINE, Received]),
{error, headers}.
slowly_connect(Node, {get, Path}, From, Timeout) ->
HttpOptions = [{connect_timeout, 3000}, {timeout, Timeout}],
URL = lists:flatten(url(Node, Path)),
Request = {URL, []},
Result =
case httpc:request(get, Request, HttpOptions, []) of
{ok, {{_, 200, _}, _, JSON}} -> zj:decode(JSON);
{ok, {{_, BAD, _}, _, _}} -> {error, BAD};
BAD -> {error, BAD}
end,
gen_server:reply(From, Result);
slowly_connect(Node, {post, Path, Payload}, From, Timeout) ->
HttpOptions = [{connect_timeout, 3000}, {timeout, Timeout}],
URL = lists:flatten(url(Node, Path)),
Request = {URL, [], "application/json", Payload},
Result =
case httpc:request(post, Request, HttpOptions, []) of
{ok, {{_, 200, _}, _, JSON}} -> zj:decode(JSON);
{ok, {{_, BAD, _}, _, _}} -> {error, BAD};
BAD -> {error, BAD}
end,
gen_server:reply(From, Result).
url({Node, Port}, Path) when is_list(Node) ->
["https://", Node, ":", integer_to_list(Port), Path];
url({Node, Port}, Path) when is_tuple(Node) ->
["https://", inet:ntoa(Node), ":", integer_to_list(Port), Path].
log(Level, Format, Args) ->
Raw = io_lib:format("~w ~w: " ++ Format, [?MODULE, self() | Args]),
Entry = unicode:characters_to_list(Raw),
logger:log(Level, Entry).