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COWBOY:START_CLEAR(3) COWBOY:START_CLEAR(3)
NAME
cowboy:start_clear - Listen for connections using plain TCP
DESCRIPTION
start_clear(Name :: ranch:ref(),
NumAcceptors :: non_neg_integer(),
TransportOpts :: ranch_tcp:opts(),
ProtocolOpts :: opts())
-> {ok, ListenerPid :: pid()}
| {error, any()}
Start listening for connections over a clear TCP channel.
Both HTTP/1.1 and HTTP/2 are supported on this listener. HTTP/2 has
two methods of establishing a connection over a clear TCP channel.
Both the upgrade and the prior knowledge methods are supported.
ARGUMENTS
Name
The listener name is used to refer to this listener in future
calls, for example when stopping it or when updating the routes
defined.
It can be any Erlang term. An atom is generally good enough, for
example api, my_app_clear or my_app_tls.
NumAcceptors
The number of acceptors is the number of processes that will
accept connections. Tweak this value to improve the accept rate
for incoming connections.
The ideal value is between 10 and 100 on most systems. Larger
values may have the opposite effect and reduce the accept rate.
It’s generally safe to start with a value of 100 (or 10 on low
memory systems). Then, when accept rates become a concern, measure
the performance and update the value accordingly.
This value is unrelated to the maximum number of concurrent
connections.
TransportOpts
The transport options are where the TCP options, including the
listener’s port number, are defined. Transport options are
provided as a list of keys and values, for example [{port, 8080}].
ProtocolOpts
The protocol options is a map containing all the options for the
different protocols that may be involved when connecting to this
listener, including HTTP/1.1 and HTTP/2 but also subprotocols like
Websocket.
RETURN VALUE
An ok tuple is returned on success. It contains the pid of the
top-level supervisor for the listener.
An error tuple is returned on error. The error reason may be any
Erlang term.
CHANGELOG
· 2.0: Function introduced. Replaces cowboy:start_http/4.
EXAMPLES
Start a listener.
Dispatch = cowboy_router:compile([
{'_', [
{"/", toppage_h, []}
]}
]),
{ok, _} = cowboy:start_clear(example, 100, [{port, 8080}], #{
env => #{dispatch => Dispatch}
}).
Start a listener on a random port.
Name = example,
{ok, _} = cowboy:start_clear(Name, 100, [], #{
env => #{dispatch => Dispatch}
}),
Port = ranch:get_port(Name).
SEE ALSO
cowboy(3), cowboy:start_tls(3), ranch(3)
09/21/2016 COWBOY:START_CLEAR(3)
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