hackney

4.5.2

4.7.2 4.7.1 4.7.0 4.6.1 4.6.0 4.5.2 4.5.1 4.5.0 4.4.5 4.4.3 4.4.2 4.4.1 4.4.0 4.3.0 4.2.3 4.2.2 4.2.1 4.2.0 4.1.0 4.0.3 4.0.2 4.0.1 4.0.0 3.2.1 3.2.0 3.1.2 3.1.1 3.1.0 3.0.3 3.0.2 3.0.1 3.0.0 retired 2.0.1 2.0.0 2.0.0-beta.1 1.25.0 1.24.1 1.24.0 1.23.0 1.22.0 1.21.0 1.20.1 1.20.0 1.19.1 1.19.0 1.18.2 1.18.1 1.18.0 1.17.4 1.17.3 1.17.2 1.17.1 1.17.0 1.16.0 1.15.2 1.15.1 1.15.0 1.14.3 1.14.2 1.14.0 1.13.0 1.12.1 1.12.0 1.11.0 1.10.1 1.10.0 1.9.0 1.8.6 1.8.5 1.8.4 1.8.3 1.8.2 1.8.0 1.7.1 1.7.0 1.6.6 retired 1.6.5 1.6.4 retired 1.6.3 1.6.2 1.6.1 1.6.0 1.5.7 1.5.6 1.5.5 1.5.4 1.5.3 1.5.2 1.5.1 1.5.0 1.4.10 1.4.8 1.4.7 1.4.6 1.4.5 1.4.4 1.4.3 1.4.2 1.4.1 1.4.0 1.3.2 1.3.1 1.3.0 1.2.0 1.1.0 1.0.6 1.0.5 1.0.2 1.0.1 0.15.2 0.15.0 0.14.3 0.14.2 0.14.1 0.14.0 0.13.1

Simple HTTP client with HTTP/1.1, HTTP/2, and HTTP/3 support

HexDocs

Current section

Files

Jump to

Readme 116 Versions 8 Dependencies Dependants 12 Advisories Files Activity

hackney src hackney_happy.erl

Raw

src/hackney_happy.erl

-module(hackney_happy).

-export([connect/3, connect/4]).
-export([connect_udp/3, connect_udp/4]).

-include("hackney_internal.hrl").
-include_lib("kernel/include/inet.hrl").

-define(TIMEOUT, 250).
-define(CONNECT_TIMEOUT, 5000).

connect(Hostname, Port, Opts) ->
  connect(Hostname, Port, Opts, ?CONNECT_TIMEOUT).

connect(Hostname, Port, Opts, Timeout) ->
  do_connect(parse_address(Hostname), Port, Opts, Timeout).

do_connect(Hostname, Port, Opts, Timeout) when is_tuple(Hostname) ->
  case hackney_cidr:is_ipv6(Hostname) of
    true ->
      ?report_debug("connect using IPv6", [{hostname, Hostname}, {port, Port}]),
      gen_tcp:connect(Hostname, Port, [inet6 | Opts], Timeout);
    false ->
      case hackney_cidr:is_ipv4(Hostname) of
        true ->
          ?report_debug("connect using IPv4", [{hostname, Hostname}, {port, Port}]),
          gen_tcp:connect(Hostname, Port, [inet | Opts], Timeout);
        false ->
          {error, nxdomain}
      end
  end;
do_connect(Hostname, Port, Opts, Timeout) ->
  ?report_debug("happy eyeballs, try to connect using IPv6",  [{hostname, Hostname}, {port, Port}, {timeout, Timeout}]),
  Self = self(),
  case getaddrs(Hostname) of
    {[], []} -> {error, nxdomain};
    {[], IPv4Addrs} ->
      ?report_trace("happy connect: try IPv4 only", []),
      {Pid4, MRef4} = spawn_monitor(fun() -> try_connect(IPv4Addrs, Port, Opts, Timeout, Self) end),
      do_connect_2(Pid4, MRef4, Timeout);
    {Ipv6Addrs, []} ->
      ?report_trace("happy connect: try IPv6 only", []),
      {Pid6, MRef6} = spawn_monitor(fun() -> try_connect(Ipv6Addrs, Port, Opts, Timeout, Self) end),
      do_connect_2(Pid6, MRef6, Timeout);
    {Ipv6Addrs, IPv4Addrs} ->
      {Pid6, MRef6} = spawn_monitor(fun() -> try_connect(Ipv6Addrs, Port, Opts, Timeout, Self) end),
      TRef = erlang:start_timer(?TIMEOUT, self(), try_ipv4),
      receive
        {'DOWN', MRef6, _Type, _Pid, {happy_connect, OK}} ->
          _ = erlang:cancel_timer(TRef, []),
          OK;
        {'DOWN', MRef6, _Type, _Pid, _Info} ->
          _ = erlang:cancel_timer(TRef, []),
          {Pid4, MRef4} = spawn_monitor(fun() -> try_connect(IPv4Addrs, Port, Opts, Timeout, Self) end),
          do_connect_2(Pid4, MRef4, Timeout);
        {timeout, TRef, try_ipv4} ->
          ?report_trace("happy connect: try IPv4", []),
          PidRef4 = spawn_monitor(fun() -> try_connect(IPv4Addrs, Port, Opts, Timeout, Self) end),
          do_connect_1(PidRef4, {Pid6, MRef6}, Timeout)
      after Timeout ->
              ?report_trace("happy, connect timeout", []),
              _ = erlang:cancel_timer(TRef, []),
              erlang:demonitor(MRef6, [flush]),
              {error, connect_timeout}
      end
  end.


do_connect_1({Pid4, MRef4}, {Pid6, MRef6}, Timeout) ->
  receive
    {'DOWN', MRef4, _Type, _Pid, {happy_connect, OK}} ->
      ?report_trace("happy_connect: ~p", [OK]),
      connect_gc(Pid6, MRef6),
      OK;
     {'DOWN', MRef6, _Type, _Pid, {happy_connect, OK}} ->
      ?report_trace("happy_connect ~p", [OK]),
      connect_gc(Pid4, MRef4),
      OK;
    {'DOWN', MRef4, _Type, _Pid, _Info} ->
      do_connect_2(Pid6, MRef6, Timeout);
    {'DOWN', MRef6, _Type, _Pid, _Info} ->
      do_connect_2(Pid4, MRef4, Timeout)
  after Timeout ->
          connect_gc(Pid4, MRef4),
          connect_gc(Pid6, MRef6),
          {error, connect_timeout}
  end.

do_connect_2(Pid, MRef, Timeout) ->
  receive
    {'DOWN', MRef, _Type, _Pid, {happy_connect, OK}} ->
      ?report_trace("happy_connect ~p", [OK]),
      OK;
    {'DOWN', MRef, _Type, _Pid, {error, _} = Error} ->
      Error;
    {'DOWN', MRef, _Type, _Pid, Info} ->
      %% Wrap unexpected exit reasons in error tuple
      {error, Info}
  after Timeout ->
          connect_gc(Pid, MRef),
          {error, connect_timeout}
  end.

connect_gc(Pid, MRef) ->
  (try exit(Pid, normal) catch _:_ -> ok end),
  erlang:demonitor(MRef, [flush]).


-spec parse_address(inet:ip_address() | binary() | string()) -> inet:ip_address() | string().
parse_address(IPTuple) when is_tuple(IPTuple) -> IPTuple;
parse_address(IPBin) when is_binary(IPBin) ->
  parse_address(binary_to_list(IPBin));
%% IPv6 string with brackets
parse_address("[" ++ IPString) ->
  parse_address(lists:sublist(IPString, length(IPString) - 1));
parse_address(IPString) ->
  case inet:parse_address(IPString) of
    {ok, IP} -> IP;
    {error, _} -> IPString
  end.

-spec getaddrs(string()) -> {[{inet:ip_address(), 'inet6' | 'inet'}], [{inet:ip_address(), 'inet6' | 'inet'}]}.
getaddrs("localhost") ->
  {[{{0,0,0,0,0,0,0,1}, 'inet6'}], [{{127,0,0,1}, 'inet'}]};
getaddrs(Name) ->
  IP6Addrs = [{Addr, 'inet6'} || Addr <- getbyname(Name, 'aaaa')],
  IP4Addrs = [{Addr, 'inet'} || Addr <- getbyname(Name, 'a')],
  {IP6Addrs, IP4Addrs}.

getbyname(Hostname, Type) ->
  %% First try DNS resolution using inet_res:getbyname
  try inet_res:getbyname(Hostname, Type) of
    {'ok', #hostent{h_addr_list=AddrList}} ->
      AddrList;
    {error, _Reason} ->
      %% DNS failed, try fallback to /etc/hosts using inet:gethostbyname
      %% This fixes NXDOMAIN errors in Docker Compose environments where
      %% hostnames are resolved via /etc/hosts entries
      fallback_hosts_lookup(Hostname, Type)
  catch
    Class:Reason ->
      ?report_debug("DNS error", [{hostname, Hostname}
                                 ,{type, Type}
                                 ,{error, {Class, Reason}}]),
      %% Try fallback on resolver crashes too
      fallback_hosts_lookup(Hostname, Type)
  end.

%% Fallback to check /etc/hosts when DNS resolution fails
fallback_hosts_lookup(Hostname, Type) ->
  InetType = case Type of
    a -> inet;
    aaaa -> inet6
  end,
  try inet:gethostbyname(Hostname, InetType) of
    {'ok', #hostent{h_addr_list=AddrList}} ->
      AddrList;
    _ ->
      []
  catch
    _:_ ->
      []
  end.

try_connect(Ipv6Addrs, Port, Opts, Timeout, Self) ->
  try_connect(Ipv6Addrs, Port, Opts, Timeout, Self, {error, nxdomain}).

try_connect([], _Port, _Opts, _Timeout, _ServerPid, LastError) ->
  ?report_trace("happy eyeball: failed to connect", [{error, LastError}]),
  exit(LastError);
try_connect([{IP, Type} | Rest], Port, Opts, Timeout, ServerPid, _LastError) ->
  ?report_trace("try to connect", [{ip, IP}, {type, Type}]),
  case gen_tcp:connect(IP, Port, [Type | Opts], Timeout) of
    {ok, Socket} = OK ->
      ?report_trace("success to connect", [{ip, IP}, {type, Type}]),
      case gen_tcp:controlling_process(Socket, ServerPid) of
        ok ->
          exit({happy_connect, OK});
        {error, Reason} ->
          ?report_trace("controlling_process failed", [{error, Reason}]),
          _ = gen_tcp:close(Socket),
          try_connect(Rest, Port, Opts, Timeout, ServerPid, {error, Reason})
      end;
    Error ->
      try_connect(Rest, Port, Opts, Timeout, ServerPid, Error)
  end.

%%====================================================================
%% UDP Happy Eyeballs (for QUIC/HTTP3)
%%====================================================================

%% @doc Connect via UDP using happy eyeballs algorithm.
%% Returns {ok, Socket, RemoteAddr} where RemoteAddr is {IP, Port}.
connect_udp(Hostname, Port, Opts) ->
  connect_udp(Hostname, Port, Opts, ?CONNECT_TIMEOUT).

connect_udp(Hostname, Port, Opts, Timeout) ->
  do_connect_udp(parse_address(Hostname), Port, Opts, Timeout).

do_connect_udp(Hostname, Port, Opts, _Timeout) when is_tuple(Hostname) ->
  case hackney_cidr:is_ipv6(Hostname) of
    true ->
      try_udp_connect(Hostname, Port, inet6, Opts);
    false ->
      case hackney_cidr:is_ipv4(Hostname) of
        true ->
          try_udp_connect(Hostname, Port, inet, Opts);
        false ->
          {error, nxdomain}
      end
  end;
do_connect_udp(Hostname, Port, Opts, Timeout) ->
  Self = self(),
  case getaddrs(Hostname) of
    {[], []} -> {error, nxdomain};
    {[], IPv4Addrs} ->
      {Pid4, MRef4} = spawn_monitor(fun() -> try_udp_list(IPv4Addrs, Port, Opts, Self) end),
      do_udp_wait(Pid4, MRef4, Timeout);
    {Ipv6Addrs, []} ->
      {Pid6, MRef6} = spawn_monitor(fun() -> try_udp_list(Ipv6Addrs, Port, Opts, Self) end),
      do_udp_wait(Pid6, MRef6, Timeout);
    {Ipv6Addrs, IPv4Addrs} ->
      {Pid6, MRef6} = spawn_monitor(fun() -> try_udp_list(Ipv6Addrs, Port, Opts, Self) end),
      TRef = erlang:start_timer(?TIMEOUT, self(), try_ipv4),
      receive
        {'DOWN', MRef6, _, _, {happy_connect, OK}} ->
          _ = erlang:cancel_timer(TRef, []),
          OK;
        {'DOWN', MRef6, _, _, _} ->
          _ = erlang:cancel_timer(TRef, []),
          {Pid4, MRef4} = spawn_monitor(fun() -> try_udp_list(IPv4Addrs, Port, Opts, Self) end),
          do_udp_wait(Pid4, MRef4, Timeout);
        {timeout, TRef, try_ipv4} ->
          PidRef4 = spawn_monitor(fun() -> try_udp_list(IPv4Addrs, Port, Opts, Self) end),
          do_udp_race(PidRef4, {Pid6, MRef6}, Timeout)
      after Timeout ->
        _ = erlang:cancel_timer(TRef, []),
        erlang:demonitor(MRef6, [flush]),
        {error, connect_timeout}
      end
  end.

do_udp_wait(Pid, MRef, Timeout) ->
  receive
    {'DOWN', MRef, _, _, {happy_connect, OK}} -> OK;
    {'DOWN', MRef, _, _, {error, _} = E} -> E;
    {'DOWN', MRef, _, _, Info} -> {error, Info}
  after Timeout ->
    connect_gc(Pid, MRef),
    {error, connect_timeout}
  end.

do_udp_race({Pid4, MRef4}, {Pid6, MRef6}, Timeout) ->
  receive
    {'DOWN', MRef4, _, _, {happy_connect, OK}} ->
      connect_gc(Pid6, MRef6), OK;
    {'DOWN', MRef6, _, _, {happy_connect, OK}} ->
      connect_gc(Pid4, MRef4), OK;
    {'DOWN', MRef4, _, _, _} ->
      do_udp_wait(Pid6, MRef6, Timeout);
    {'DOWN', MRef6, _, _, _} ->
      do_udp_wait(Pid4, MRef4, Timeout)
  after Timeout ->
    connect_gc(Pid4, MRef4),
    connect_gc(Pid6, MRef6),
    {error, connect_timeout}
  end.

try_udp_list(Addrs, Port, Opts, ServerPid) ->
  try_udp_list_1(Addrs, Port, Opts, ServerPid, {error, nxdomain}).

try_udp_list_1([], _Port, _Opts, _ServerPid, LastError) ->
  exit(LastError);
try_udp_list_1([{IP, Type} | Rest], Port, Opts, ServerPid, _LastError) ->
  case try_udp_connect(IP, Port, Type, Opts) of
    {ok, Socket, RemoteAddr} ->
      %% Transfer socket ownership to parent process before exiting
      case gen_udp:controlling_process(Socket, ServerPid) of
        ok ->
          exit({happy_connect, {ok, Socket, RemoteAddr}});
        {error, Reason} ->
          gen_udp:close(Socket),
          try_udp_list_1(Rest, Port, Opts, ServerPid, {error, Reason})
      end;
    Error ->
      try_udp_list_1(Rest, Port, Opts, ServerPid, Error)
  end.

try_udp_connect(IP, Port, Type, Opts) ->
  UdpOpts = [binary, {active, false}, Type | proplists:delete(inet, proplists:delete(inet6, Opts))],
  case gen_udp:open(0, UdpOpts) of
    {ok, Socket} ->
      case gen_udp:connect(Socket, IP, Port) of
        ok -> {ok, Socket, {IP, Port}};
        {error, Reason} ->
          gen_udp:close(Socket),
          {error, Reason}
      end;
    {error, _} = Error -> Error
  end.

Operator	Description	Example
name:	Match package name. Supports * wildcards and repo/package form	name:phx* or name:hexpm/phoenix
description:	Full-text search of package descriptions	description:auth
depends:	Packages depending on a given package. Supports repo:package form	depends:ecto or depends:hexpm:ecto
build_tool:	Filter by build tool	build_tool:mix
updated_after:	Packages updated after an ISO8601 datetime	updated_after:2025-01-01T00:00:00Z
extra:	Match custom metadata (key,value). Nested keys are separated by commas	extra:license,MIT