%%% -*- erlang -*-
%%%
%%% This file is part of hackney released under the Apache 2 license.
%%% See the NOTICE for more information.
%%%
%%% Copyright (c) 2024-2026 Benoit Chesneau
%%%
%%% @doc HTTP/3 support for hackney.
%%%
%%% This module provides HTTP/3 functionality using the QUIC NIF.
%%% It handles stream management, header encoding, and request/response
%%% handling for HTTP/3 connections over QUIC.
%%%
%%% == Usage ==
%%%
%%% ```
%%% %% Check if HTTP/3 is available
%%% hackney_h3:is_available() -> boolean()
%%%
%%% %% Make a simple GET request
%%% {ok, Status, Headers, Body} = hackney_h3:request(get, "https://cloudflare.com/")
%%%
%%% %% Make a request with options
%%% {ok, Status, Headers, Body} = hackney_h3:request(get, "https://example.com/",
%%% [{<<"user-agent">>, <<"hackney/2.0">>}], <<>>, #{timeout => 30000})
%%% '''
%%%
-module(hackney_h3).
-include("hackney_lib.hrl").
-export([
%% High-level API
is_available/0,
request/2, request/3, request/4, request/5,
connect/2, connect/3,
await_response/2,
%% Request operations (used by hackney_conn)
send_request/6,
send_request_headers/5,
send_body_chunk/4,
finish_send_body/3,
%% Stream management
new_stream/1,
close_stream/2,
get_stream_state/2,
update_stream_state/3,
%% Response parsing
parse_response_headers/1,
%% Connection close
close/1,
close/2
]).
-type h3_conn() :: reference().
-type stream_id() :: non_neg_integer().
-type method() :: get | post | put | delete | head | options | patch | atom() | binary().
-type url() :: binary() | string().
-type headers() :: [{binary(), binary()}].
-type body() :: binary() | iodata().
-type response() :: {ok, integer(), headers(), binary()} | {error, term()}.
-type stream_state() :: waiting_headers | {receiving_body, integer(), headers(), binary()} | done.
-type streams_map() :: #{stream_id() => {term(), stream_state()}}.
-export_type([h3_conn/0, stream_id/0, stream_state/0, streams_map/0]).
%%====================================================================
%% High-level API
%%====================================================================
%% @doc Check if HTTP/3/QUIC support is available.
-spec is_available() -> boolean().
is_available() ->
hackney_quic:is_available().
%% @doc Make an HTTP/3 request with default options.
-spec request(method(), url()) -> response().
request(Method, Url) ->
request(Method, Url, [], <<>>, #{}).
%% @doc Make an HTTP/3 request with headers.
-spec request(method(), url(), headers()) -> response().
request(Method, Url, Headers) ->
request(Method, Url, Headers, <<>>, #{}).
%% @doc Make an HTTP/3 request with headers and body.
-spec request(method(), url(), headers(), body()) -> response().
request(Method, Url, Headers, Body) ->
request(Method, Url, Headers, Body, #{}).
%% @doc Make an HTTP/3 request with all options.
%%
%% Options:
%% - timeout: Request timeout in milliseconds (default: 30000)
%% - recv_timeout: Response receive timeout (default: 30000)
%%
-spec request(method(), url(), headers(), body(), map()) -> response().
request(Method, Url, Headers, Body, Opts) ->
#hackney_url{host = Host, port = Port, path = Path} = hackney_url:parse_url(Url),
HostBin = list_to_binary(Host),
PathBin = case Path of
<<>> -> <<"/">>;
_ -> Path
end,
Timeout = maps:get(timeout, Opts, 30000),
case connect(HostBin, Port, Opts) of
{ok, Conn} ->
try
do_request(Conn, Method, HostBin, PathBin, Headers, Body, Timeout)
after
close(Conn)
end;
{error, _} = Error ->
Error
end.
%% @doc Connect to an HTTP/3 server.
-spec connect(binary() | string(), inet:port_number()) -> {ok, reference()} | {error, term()}.
connect(Host, Port) ->
connect(Host, Port, #{}).
%% @doc Connect to an HTTP/3 server with options.
%% lsquic handles its own UDP socket creation and DNS resolution.
-spec connect(binary() | string(), inet:port_number(), map()) -> {ok, reference()} | {error, term()}.
connect(Host, Port, Opts) when is_list(Host) ->
connect(list_to_binary(Host), Port, Opts);
connect(Host, Port, Opts) when is_binary(Host) ->
Timeout = maps:get(timeout, Opts, 30000),
case hackney_quic:connect(Host, Port, Opts, self()) of
{ok, ConnRef} ->
wait_connected(ConnRef, Timeout, erlang:monotonic_time(millisecond));
{error, _} = Error ->
Error
end.
%% @doc Wait for an HTTP/3 response.
-spec await_response(reference(), non_neg_integer()) ->
{ok, integer(), headers(), binary()} | {error, term()}.
await_response(ConnRef, StreamId) ->
await_response_loop(ConnRef, StreamId, 30000, undefined, [], <<>>, erlang:monotonic_time(millisecond)).
%%====================================================================
%% Request operations (used by hackney_conn)
%%====================================================================
%% @doc Send a complete HTTP/3 request (headers + body).
%% Returns {ok, StreamId, UpdatedStreams} or {error, Reason}.
-spec send_request(h3_conn(), method(), binary(), binary(), headers(), binary()) ->
{ok, stream_id(), streams_map()} | {error, term()}.
send_request(ConnRef, Method, Host, Path, Headers, Body) ->
case hackney_quic:open_stream(ConnRef) of
{ok, StreamId} ->
AllHeaders = build_request_headers(Method, Host, Path, Headers),
HasBody = Body =/= <<>> andalso Body =/= [],
Fin = not HasBody,
case hackney_quic:send_headers(ConnRef, StreamId, AllHeaders, Fin) of
ok when HasBody ->
case hackney_quic:send_data(ConnRef, StreamId, Body, true) of
ok ->
{ok, StreamId, #{StreamId => {undefined, waiting_headers}}};
{error, _} = Error ->
Error
end;
ok ->
{ok, StreamId, #{StreamId => {undefined, waiting_headers}}};
{error, _} = Error ->
Error
end;
{error, _} = Error ->
Error
end.
%% @doc Send HTTP/3 request headers only (for streaming body).
%% Returns {ok, StreamId, UpdatedStreams} or {error, Reason}.
-spec send_request_headers(h3_conn(), method(), binary(), binary(), headers()) ->
{ok, stream_id(), streams_map()} | {error, term()}.
send_request_headers(ConnRef, Method, Host, Path, Headers) ->
case hackney_quic:open_stream(ConnRef) of
{ok, StreamId} ->
AllHeaders = build_request_headers(Method, Host, Path, Headers),
case hackney_quic:send_headers(ConnRef, StreamId, AllHeaders, false) of
ok ->
{ok, StreamId, #{StreamId => {undefined, waiting_headers}}};
{error, _} = Error ->
Error
end;
{error, _} = Error ->
Error
end.
%% @doc Send a chunk of body data on a stream.
-spec send_body_chunk(h3_conn(), stream_id(), binary(), boolean()) ->
ok | {error, term()}.
send_body_chunk(ConnRef, StreamId, Data, Fin) ->
hackney_quic:send_data(ConnRef, StreamId, Data, Fin).
%% @doc Finish sending body (close stream for writing).
-spec finish_send_body(h3_conn(), stream_id(), streams_map()) ->
{ok, streams_map()} | {error, term()}.
finish_send_body(ConnRef, StreamId, Streams) ->
case hackney_quic:send_data(ConnRef, StreamId, <<>>, true) of
ok ->
{ok, Streams};
{error, _} = Error ->
Error
end.
%%====================================================================
%% Stream management
%%====================================================================
%% @doc Open a new stream for a request.
-spec new_stream(h3_conn()) -> {ok, stream_id()} | {error, term()}.
new_stream(ConnRef) ->
hackney_quic:open_stream(ConnRef).
%% @doc Close a specific stream.
-spec close_stream(h3_conn(), stream_id()) -> ok.
close_stream(_ConnRef, _StreamId) ->
%% HTTP/3 streams are closed when fin is sent/received
ok.
%% @doc Get the state of a specific stream.
-spec get_stream_state(stream_id(), streams_map()) ->
{ok, {term(), stream_state()}} | {error, not_found}.
get_stream_state(StreamId, Streams) ->
case maps:find(StreamId, Streams) of
{ok, State} -> {ok, State};
error -> {error, not_found}
end.
%% @doc Update the state of a stream.
-spec update_stream_state(stream_id(), {term(), stream_state()}, streams_map()) ->
streams_map().
update_stream_state(StreamId, State, Streams) ->
maps:put(StreamId, State, Streams).
%%====================================================================
%% Response parsing
%%====================================================================
%% @doc Parse response headers from a QUIC stream_headers event.
%% Returns {ok, Status, ResponseHeaders} or {error, Reason}.
-spec parse_response_headers(headers()) -> {ok, integer(), headers()} | {error, term()}.
parse_response_headers(Headers) ->
case get_status_from_headers(Headers) of
{ok, Status} ->
RespHeaders = filter_pseudo_headers(Headers),
{ok, Status, RespHeaders};
{error, _} = Error ->
Error
end.
%%====================================================================
%% Connection close
%%====================================================================
%% @doc Close the HTTP/3 connection.
-spec close(h3_conn()) -> ok.
close(ConnRef) ->
close(ConnRef, normal).
%% @doc Close the HTTP/3 connection with a reason.
-spec close(h3_conn(), term()) -> ok.
close(ConnRef, Reason) ->
hackney_quic:close(ConnRef, Reason).
%%====================================================================
%% Internal functions
%%====================================================================
%% Drive QUIC event loop until connected
wait_connected(ConnRef, Timeout, StartTime) ->
Elapsed = erlang:monotonic_time(millisecond) - StartTime,
Remaining = max(0, Timeout - Elapsed),
receive
{select, _Resource, _Ref, ready_input} ->
_ = hackney_quic:process(ConnRef),
wait_connected(ConnRef, Timeout, StartTime);
{quic, ConnRef, {connected, _Info}} ->
{ok, ConnRef};
{quic, ConnRef, {closed, Reason}} ->
{error, {connection_closed, Reason}};
{quic, ConnRef, {transport_error, Code, Msg}} ->
{error, {transport_error, Code, Msg}}
after Remaining ->
hackney_quic:close(ConnRef, timeout),
{error, timeout}
end.
do_request(ConnRef, Method, Host, Path, Headers, Body, Timeout) ->
case hackney_quic:open_stream(ConnRef) of
{ok, StreamId} ->
AllHeaders = build_request_headers(Method, Host, Path, Headers),
HasBody = Body =/= <<>> andalso Body =/= [],
Fin = not HasBody,
case hackney_quic:send_headers(ConnRef, StreamId, AllHeaders, Fin) of
ok when HasBody ->
case hackney_quic:send_data(ConnRef, StreamId, Body, true) of
ok ->
await_response_loop(ConnRef, StreamId, Timeout, undefined, [], <<>>, erlang:monotonic_time(millisecond));
{error, _} = Error ->
Error
end;
ok ->
await_response_loop(ConnRef, StreamId, Timeout, undefined, [], <<>>, erlang:monotonic_time(millisecond));
{error, _} = Error ->
Error
end;
{error, _} = Error ->
Error
end.
await_response_loop(ConnRef, StreamId, Timeout, Status, Headers, AccBody, StartTime) ->
Elapsed = erlang:monotonic_time(millisecond) - StartTime,
Remaining = max(0, Timeout - Elapsed),
receive
{select, _Resource, _Ref, ready_input} ->
_ = hackney_quic:process(ConnRef),
await_response_loop(ConnRef, StreamId, Timeout, Status, Headers, AccBody, StartTime);
{quic, ConnRef, {stream_headers, StreamId, RespHeaders, _Fin}} ->
NewStatus = get_status(RespHeaders),
FilteredHeaders = filter_pseudo_headers(RespHeaders),
await_response_loop(ConnRef, StreamId, Timeout, NewStatus, FilteredHeaders, AccBody, StartTime);
{quic, ConnRef, {stream_data, StreamId, Data, Fin}} ->
NewBody = <<AccBody/binary, Data/binary>>,
case Fin of
true ->
{ok, Status, Headers, NewBody};
false ->
await_response_loop(ConnRef, StreamId, Timeout, Status, Headers, NewBody, StartTime)
end;
{quic, ConnRef, {stream_reset, StreamId, _ErrorCode}} ->
{error, stream_reset};
{quic, ConnRef, {closed, Reason}} ->
{error, {connection_closed, Reason}}
after Remaining ->
{error, timeout}
end.
%% @private Build HTTP/3 request headers including pseudo-headers.
-spec build_request_headers(method(), binary(), binary(), headers()) -> headers().
build_request_headers(Method, Host, Path, Headers) ->
MethodBin = method_to_binary(Method),
PseudoHeaders = [
{<<":method">>, MethodBin},
{<<":path">>, Path},
{<<":scheme">>, <<"https">>},
{<<":authority">>, Host}
],
PseudoHeaders ++ normalize_headers(Headers).
%% @private Convert HTTP method to binary.
-spec method_to_binary(method()) -> binary().
method_to_binary(get) -> <<"GET">>;
method_to_binary(post) -> <<"POST">>;
method_to_binary(put) -> <<"PUT">>;
method_to_binary(delete) -> <<"DELETE">>;
method_to_binary(head) -> <<"HEAD">>;
method_to_binary(options) -> <<"OPTIONS">>;
method_to_binary(patch) -> <<"PATCH">>;
method_to_binary(Method) when is_atom(Method) ->
string:uppercase(atom_to_binary(Method));
method_to_binary(Method) when is_binary(Method) ->
Method.
%% @private Normalize headers to binary key-value pairs.
-spec normalize_headers(headers()) -> headers().
normalize_headers(Headers) ->
[{ensure_binary(K), ensure_binary(V)} || {K, V} <- Headers].
%% @private Ensure value is binary.
-spec ensure_binary(term()) -> binary().
ensure_binary(B) when is_binary(B) -> B;
ensure_binary(L) when is_list(L) -> list_to_binary(L);
ensure_binary(A) when is_atom(A) -> atom_to_binary(A).
%% @private Extract status from HTTP/3 response headers (returns integer or 0).
-spec get_status(headers()) -> integer().
get_status(Headers) ->
case lists:keyfind(<<":status">>, 1, Headers) of
{_, StatusBin} ->
binary_to_integer(StatusBin);
false ->
0
end.
%% @private Extract status from HTTP/3 response headers (returns ok/error tuple).
-spec get_status_from_headers(headers()) -> {ok, integer()} | {error, no_status | {invalid_status, binary()}}.
get_status_from_headers(Headers) ->
case lists:keyfind(<<":status">>, 1, Headers) of
{_, StatusBin} ->
try
{ok, binary_to_integer(StatusBin)}
catch
error:badarg -> {error, {invalid_status, StatusBin}}
end;
false ->
{error, no_status}
end.
%% @private Filter out pseudo-headers from response.
-spec filter_pseudo_headers(headers()) -> headers().
filter_pseudo_headers(Headers) ->
[{K, V} || {K, V} <- Headers, not is_pseudo_header(K)].
%% @private Check if header is a pseudo-header (starts with ':').
-spec is_pseudo_header(binary()) -> boolean().
is_pseudo_header(<<$:, _/binary>>) -> true;
is_pseudo_header(_) -> false.