This library wraps gen_tcp
, gen_udp
and gen_sctp
, ssl
and implements
websockets and socks.
In your mix.exs
file
defp deps do
[
# ...
{:socket, "~> 0.3"},
# ...
]
end
Then run mix deps.get
to install
defmodule HTTP do
def get(uri) when is_binary(uri) or is_list(uri) do
get(URI.parse(uri))
end
def get(%URI{host: host, port: port, path: path}) do
sock = Socket.TCP.connect! host, port, packet: :line
sock |> Socket.Stream.send! "GET #{path || "/"} HTTP/1.1\r\nHost: #{host}\r\n\r\n"
[_, code, text] = Regex.run ~r"HTTP/1.1 (.*?) (.*?)\s*$", sock |> Socket.Stream.recv!
headers = headers([], sock) |> Enum.into(%{})
sock |> Socket.packet! :raw
body = sock |> Socket.Stream.recv!(String.to_integer(headers["Content-Length"]))
{ { String.to_integer(code), text }, headers, body }
end
defp headers(acc, sock) do
case sock |> Socket.Stream.recv! do
"\r\n" ->
acc
line ->
[_, name, value] = Regex.run ~r/^(.*?):\s*(.*?)\s*$/, line
headers([{ name, value } | acc], sock)
end
end
end
socket = Socket.Web.connect! "echo.websocket.org"
socket |> Socket.Web.send! { :text, "test" }
socket |> Socket.Web.recv! # => {:text, "test"}
In order to connect to a TLS websocket, use the secure: true
option:
socket = Socket.Web.connect! "echo.websocket.org", secure: true
The connect!
function also accepts other parameters, most notably the path
parameter, which is used when the websocket server endpoint exists on a path below the domain ie. "example.com/websocket":
socket = Socket.Web.connect! "example.com", path: "/websocket"
Note that websocket servers send ping messages. A pong reply from your client tells the server to keep the connection open and to send more data. If your client doesn't send a pong reply then the server will close the connection. Here's an example of how to get get both the data you want and reply to a server's pings:
socket = Socket.Web.connect! "echo.websocket.org"
case socket |> Socket.Web.recv! do
{:text, data} ->
# process data
{:ping, _ } ->
socket |> Socket.Web.send!({:pong, ""})
end
server = Socket.Web.listen! 80
client = server |> Socket.Web.accept!
# here you can verify if you want to accept the request or not, call
# `Socket.Web.close!` if you don't want to accept it, or else call
# `Socket.Web.accept!`
client |> Socket.Web.accept!
# echo the first message
client |> Socket.Web.send!(client |> Socket.Web.recv!)