class TCPServer

Overview

A Transmission Control Protocol (TCP/IP) server.

Usage example:

require "socket"

def handle_client(client)
  message = client.gets
  client.puts message
end

server = TCPServer.new("localhost", 1234)
while client = server.accept?
  spawn handle_client(client)
end

Options:

Included Modules

Defined in:

Constructors

Class Method Summary

Instance Method Summary

Instance methods inherited from module Socket::Server

accept : IO
accept(&)
accept
, accept? : IO?
accept?(&)
accept?

Instance methods inherited from class TCPSocket

tcp_keepalive_count tcp_keepalive_count, tcp_keepalive_count=(val : Int) tcp_keepalive_count=, tcp_keepalive_idle tcp_keepalive_idle, tcp_keepalive_idle=(val : Int) tcp_keepalive_idle=, tcp_keepalive_interval tcp_keepalive_interval, tcp_keepalive_interval=(val : Int) tcp_keepalive_interval=, tcp_nodelay=(val : Bool) tcp_nodelay=, tcp_nodelay? tcp_nodelay?

Constructor methods inherited from class TCPSocket

new(host, port, dns_timeout = nil, connect_timeout = nil)
new(family : Family = Family::INET)
new(*, fd : Int32, family : Family = Family::INET)
new

Class methods inherited from class TCPSocket

open(host, port, &) open

Instance methods inherited from class IPSocket

local_address local_address, remote_address remote_address

Instance methods inherited from class Socket

accept : Socket accept, accept? accept?, bind(addr, &)
bind(host : String, port : Int)
bind(port : Int)
bind(addr)
bind
, blocking blocking, blocking=(value) blocking=, broadcast=(val : Bool) broadcast=, broadcast? broadcast?, close_on_exec=(arg : Bool) close_on_exec=, close_on_exec? close_on_exec?, close_read close_read, close_write close_write, closed? : Bool closed?, connect(addr, timeout = nil, &)
connect(addr, timeout = nil) : Nil
connect(host : String, port : Int, connect_timeout = nil)
connect
, family : Family family, fcntl(cmd, arg = 0) fcntl, fd : Int32 fd, finalize finalize, getsockopt(optname, optval, level = LibC::SOL_SOCKET) getsockopt, inspect(io : IO) : Nil inspect, keepalive=(val : Bool) keepalive=, keepalive? keepalive?, linger linger, linger=(val : Int?) linger=, listen(backlog : Int = SOMAXCONN)
listen(backlog : Int = SOMAXCONN, &)
listen
, protocol : Protocol protocol, receive(max_message_size = 512) : Tuple(String, Address)
receive(message : Bytes) : Tuple(Int32, Address)
receive
, recv_buffer_size recv_buffer_size, recv_buffer_size=(val : Int32) recv_buffer_size=, reuse_address=(val : Bool) reuse_address=, reuse_address? reuse_address?, reuse_port=(val : Bool) reuse_port=, reuse_port? reuse_port?, send(message, to addr : Address) : Int32
send(message) : Int32
send
, send_buffer_size send_buffer_size, send_buffer_size=(val : Int32) send_buffer_size=, setsockopt(optname, optval, level = LibC::SOL_SOCKET) setsockopt, tty? tty?, type : Type type

Constructor methods inherited from class Socket

new(fd : Int32, family, type, protocol = Protocol::IP, blocking = false)
new(family, type, protocol = Protocol::IP, blocking = false)
new

Class methods inherited from class Socket

fcntl(fd, cmd, arg = 0) fcntl, ip?(string : String) ip?, tcp(family : Family, blocking = false) tcp, udp(family : Family, blocking = false) udp, unix(type : Type = Type::STREAM, blocking = false) unix

Instance methods inherited from module IO::Evented

evented_close evented_close, evented_read(slice : Bytes, errno_msg : String, &) : Int32 evented_read, evented_reopen evented_reopen, evented_send(slice : Bytes, errno_msg : String, &) : Int32 evented_send, evented_write(slice : Bytes, errno_msg : String, &) : Nil evented_write, read_timeout : Time::Span? read_timeout, read_timeout=(read_timeout : Number) : Number
read_timeout=(timeout : Time::Span?) : Time::Span?
read_timeout=
, write_timeout : Time::Span? write_timeout, write_timeout=(write_timeout : Number) : Number
write_timeout=(timeout : Time::Span?) : Time::Span?
write_timeout=

Instance methods inherited from module IO::Buffered

buffer_size buffer_size, buffer_size=(value) buffer_size=, close : Nil close, flush flush, peek : Bytes? peek, read(slice : Bytes) read, read_buffering=(read_buffering) read_buffering=, read_buffering? read_buffering?, rewind rewind, sync=(sync) sync=, sync? sync?, unbuffered_close unbuffered_close, unbuffered_flush unbuffered_flush, unbuffered_read(slice : Bytes) unbuffered_read, unbuffered_rewind unbuffered_rewind, unbuffered_write(slice : Bytes) unbuffered_write, write(slice : Bytes) : Nil write

Instance methods inherited from class IO

<<(obj) : self <<, close close, closed? closed?, each_byte(&) : Nil
each_byte
each_byte
, each_char(&) : Nil
each_char
each_char
, each_line(*args, **options, &block : String -> ) : Nil
each_line(*args, **options)
each_line
, encoding : String encoding, flush flush, gets(delimiter : Char, limit : Int, chomp = false) : String?
gets(delimiter : Char, chomp = false) : String?
gets(chomp = true) : String?
gets(limit : Int, chomp = false) : String?
gets(delimiter : String, chomp = false) : String?
gets
, gets_to_end : String gets_to_end, peek : Bytes? peek, pos pos, pos=(value) pos=, print(*objects : _) : Nil
print(obj) : Nil
print
, printf(format_string, *args) : Nil
printf(format_string, args : Array | Tuple) : Nil
printf
, puts(*objects : _) : Nil
puts : Nil
puts(obj) : Nil
puts(string : String) : Nil
puts
, read(slice : Bytes) read, read_at(offset, bytesize, &) read_at, read_byte : UInt8? read_byte, read_bytes(type, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) read_bytes, read_char : Char? read_char, read_fully(slice : Bytes) read_fully, read_fully?(slice : Bytes) read_fully?, read_line(*args, **options) : String read_line, read_string(bytesize : Int) : String read_string, read_utf8(slice : Bytes) read_utf8, read_utf8_byte read_utf8_byte, rewind rewind, seek(offset, whence : Seek = Seek::Set) seek, set_encoding(encoding : String, invalid : Symbol? = nil) set_encoding, skip(bytes_count : Int) : Nil skip, skip_to_end : Nil skip_to_end, tell tell, tty? : Bool tty?, write(slice : Bytes) : Nil write, write_byte(byte : UInt8) write_byte, write_bytes(object, format : IO::ByteFormat = IO::ByteFormat::SystemEndian) write_bytes, write_utf8(slice : Bytes) write_utf8

Class methods inherited from class IO

copy(src, dst, limit : Int) : UInt64
copy(src, dst) : UInt64
copy
, pipe(read_blocking = false, write_blocking = false) : Tuple(IO::FileDescriptor, IO::FileDescriptor)
pipe(read_blocking = false, write_blocking = false, &)
pipe

Instance methods inherited from class Reference

==(other : self)
==(other : JSON::Any)
==(other : YAML::Any)
==(other)
==
, dup dup, hash(hasher) hash, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference)
same?(other : Nil)
same?
, to_s(io : IO) : Nil to_s

Constructor methods inherited from class Reference

new new

Instance methods inherited from class Object

!=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other)
===
, =~(other) =~, __crystal_pseudo_! : Bool __crystal_pseudo_!, __crystal_pseudo_as(type : Class) __crystal_pseudo_as, __crystal_pseudo_as?(type : Class) __crystal_pseudo_as?, __crystal_pseudo_is_a?(type : Class) : Bool __crystal_pseudo_is_a?, __crystal_pseudo_nil? : Bool __crystal_pseudo_nil?, __crystal_pseudo_responds_to?(name : Symbol) : Bool __crystal_pseudo_responds_to?, class class, dup dup, hash(hasher)
hash
hash
, in?(*values : Object) : Bool
in?(collection) : Bool
in?
, inspect : String
inspect(io : IO) : Nil
inspect
, itself itself, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, tap(&) tap, to_json
to_json(io : IO)
to_json
, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ")
to_pretty_json
, to_s : String
to_s(io : IO) : Nil
to_s
, to_yaml(io : IO)
to_yaml
to_yaml
, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

Class methods inherited from class Object

from_json(string_or_io, root : String)
from_json(string_or_io)
from_json
, from_yaml(string_or_io : String | IO) from_yaml

Constructor Detail

def self.new(host : String, port : Int, backlog : Int = SOMAXCONN, dns_timeout = nil, reuse_port : Bool = false) #

Binds a socket to the host and port combination.


def self.new(family : Family = Family::INET) #

Creates a new TCPServer, waiting to be bound.


def self.new(port : Int, backlog = SOMAXCONN, reuse_port = false) #

Creates a new TCP server, listening on all local interfaces (::).


def self.new(*, fd : Int32, family : Family = Family::INET) #

Creates a TCPServer from an already configured raw file descriptor


Class Method Detail

def self.open(port : Int, backlog = SOMAXCONN, reuse_port = false, &) #

Creates a new TCP server, listening on all interfaces, and yields it to the block. Eventually closes the server socket when the block returns.

Returns the value of the block.


def self.open(host, port, backlog = SOMAXCONN, reuse_port = false, &) #

Creates a new TCP server and yields it to the block. Eventually closes the server socket when the block returns.

Returns the value of the block.


Instance Method Detail

def accept? : TCPSocket? #

Accepts an incoming connection.

Returns the client TCPSocket or nil if the server is closed after invoking this method.

require "socket"

server = TCPServer.new(2022)
loop do
  if socket = server.accept?
    # handle the client in a fiber
    spawn handle_connection(socket)
  else
    # another fiber closed the server
    break
  end
end