buoy

High-Performance Erlang HTTP 1.1 Client

Build Status

Disclaimer:

This HTTP client has been designed for HTTP 1.1 with keep-alive. For performance reasons, it only implements a subset of RFC2616.

Unsupported Features:

Doesn't accept an arbitrary number of new lines in headers
Doesn't accept random capitalization of content-length header
Doesn't protect against malicious servers

API

Function reference on hexdocs

Examples

1> buoy_app:start().
{ok,[telemetry,knot,metal,foil,shackle,buoy]}

2> Url = buoy_utils:parse_url(<<"http://example.com">>).
{buoy_url,<<"example.com">>,<<"example.com">>,<<"/">>,80,
          http}

3> ok = buoy_pool:start(Url, [{pool_size, 1}]).
ok

4> {ok, Resp} = buoy:get(Url, #{timeout => 500}).
{ok,{buoy_resp,done,
               <<"<!doctype html>\n<html>\n<head>\n    <title>Example Domain</title>\n\n    <meta charset=\"utf-8\" />\n  "...>>,
               1270,
               [<<"Cache-Control: max-age=604800">>,
                <<"Content-Type: text/html">>,
                <<"Date: Mon, 20 Mar 2017 14:48:25 GMT">>,
                <<"Etag: \"359670651+gzip+ident\"">>,
                <<"Expires: Mon, 27 Mar 2017 14:48:25 GMT">>,
                <<"Last-Modified: Fri, 09 Aug 2013 23:54:35 GMT">>,
                <<"Server: ECS (cpm/F9D5)">>,<<"Vary: Accept-Encoding">>,
                <<"X-Cache: HIT">>,<<"Content-Length: 1270">>],
               <<"OK">>,200}}

5> {ok, Headers} = buoy_protocol:headers(Resp).
{ok,[{<<"Cache-Control">>,<<"max-age=604800">>},
     {<<"Content-Type">>,<<"text/html">>},
     {<<"Date">>,<<"Mon, 20 Mar 2017 14:48:25 GMT">>},
     {<<"Etag">>,<<"\"359670651+gzip+ident\"">>},
     {<<"Expires">>,<<"Mon, 27 Mar 2017 14:48:25 GMT">>},
     {<<"Last-Modified">>,<<"Fri, 09 Aug 2013 23:54:35 GMT">>},
     {<<"Server">>,<<"ECS (cpm/F9D5)">>},
     {<<"Vary">>,<<"Accept-Encoding">>},
     {<<"X-Cache">>,<<"HIT">>},
     {<<"Content-Length">>,<<"1270">>}]}

Pool Options

Name	Type	Default	Description
backlog_size	pos_integer()	1024	maximum number of concurrent requests per connection
pool_size	pos_integer()	16	number of connections
pool_strategy	random \| round_robin	random	connection selection strategy
reconnect	boolean()	true	reconnect closed connections
reconnect_time_max	pos_integer() \| infinity	120000	reconnect maximum time
reconnect_time_min	pos_integer()	500	reconnect minimum time
socket_options	[gen_tcp:connect_option() \| ssl:tls_client_option()]	[binary, {packet, line}, {packet, raw}, {send_timeout, 50}, {send_timeout_close, true}]	options passed to the socket when connecting

Errors

All buoy:* calls return {ok, term()} | {error, error_reason()} where error_reason/0 (exported, added in 0.2.8) enumerates:

buoy-level — pool_not_started, buoy_not_started, pool_already_started, invalid_url.
HTTP parser — invalid_headers, invalid_chunk_size (surfaced by buoy_protocol via shackle's handle_data callback when a malformed response arrives).
shackle that propagate through buoy — no_server, shackle_not_started, timeout.

error/0 itself stays {error, term()} (not the tight sum) — see include/buoy.hrl for the rationale, briefly: buoy_client's responses/5 has a {error, not_enough_data} buffering branch that's semantically required at runtime but unreachable from dialyzer's flow analysis when error/0 is a closed sum. error_reason/0 covers the documentation half without the analyzer cost.

Telemetry

buoy emits two telemetry events at the request boundary. Attach handlers via telemetry:attach/4:

Event	Measurements	Metadata
`[buoy, request, sent]`	`count => 1`	`method, host, async`
`[buoy, request, error]`	`count => 1`	`method, host, reason`

sent fires when the request hits shackle for dispatch (sync and async paths both); error fires when the pool lookup fails (e.g. pool_not_started). Per-request lifecycle (queue / send / receive) remains observable via shackle's own telemetry — buoy's events surface the buoy-level routing decision without duplicating that work.

Tests

make test

License

The MIT License (MIT)

Copyright (c) 2016-2026 Louis-Philippe Gauthier

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.