struct Socket::Addrinfo
Overview
Domain name resolver.
Query Concurrency Behaviour
On most platforms, DNS queries are currently resolved synchronously. Calling a resolve method blocks the entire thread until it returns. This can cause latencies, especially in single-threaded processes.
DNS queries resolve asynchronously on the following platforms:
- Windows 8 and higher
NOTE Follow the discussion in Async DNS resolution (#13619) for more details.
Included Modules
- Crystal::System::Addrinfo
Defined in:
socket/addrinfo.crClass Method Summary
-
.resolve(domain : String, service, family : Family | Nil = nil, type : Type = nil, protocol : Protocol = Protocol::IP, timeout = nil) : Array(Addrinfo)
Resolves a domain that best matches the given options.
-
.resolve(domain : String, service, family : Family | Nil = nil, type : Type = nil, protocol : Protocol = Protocol::IP, timeout = nil, &)
Resolves a domain that best matches the given options.
- .tcp(domain : String, service, family = Family::UNSPEC, timeout = nil) : Array(Addrinfo)
-
.tcp(domain : String, service, family = Family::UNSPEC, timeout = nil, &)
Resolves a domain for the TCP protocol with STREAM type, and yields each possible
Addrinfo. - .udp(domain : String, service, family = Family::UNSPEC, timeout = nil) : Array(Addrinfo)
-
.udp(domain : String, service, family = Family::UNSPEC, timeout = nil, &)
Resolves a domain for the UDP protocol with DGRAM type, and yields each possible
Addrinfo.
Instance Method Summary
- #family : Family
-
#inspect(io : IO)
Appends this struct's name and instance variables names and values to the given IO.
-
#ip_address : Socket::IPAddress
Returns an
IPAddressmatching this addrinfo. - #protocol : Protocol
- #size : Int32
- #type : Type
Instance methods inherited from module Crystal::System::Addrinfo
system_ip_address : ::Socket::IPAddress
system_ip_address,
to_unsafe
to_unsafe
Class methods inherited from module Crystal::System::Addrinfo
free_addrinfo(addrinfo : Handle)
free_addrinfo,
getaddrinfo(domain, service, family, type, protocol, timeout, & : ::Socket::Addrinfo -> )getaddrinfo(domain, service, family, type, protocol, timeout) : Handle getaddrinfo, next_addrinfo(addrinfo : Handle) : Handle next_addrinfo
Instance methods inherited from struct Struct
==(other) : Bool
==,
hash(hasher)
hash,
inspect(io : IO) : Nil
inspect,
pretty_print(pp) : Nil
pretty_print,
to_s(io : IO) : Nil
to_s
Instance methods inherited from struct Value
==(other : JSON::Any)==(other : YAML::Any)
==(other) ==, dup dup
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String 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
Macros inherited from class Object
class_getter(*names, &block)
class_getter,
class_getter!(*names)
class_getter!,
class_getter?(*names, &block)
class_getter?,
class_property(*names, &block)
class_property,
class_property!(*names)
class_property!,
class_property?(*names, &block)
class_property?,
class_setter(*names)
class_setter,
def_clone
def_clone,
def_equals(*fields)
def_equals,
def_equals_and_hash(*fields)
def_equals_and_hash,
def_hash(*fields)
def_hash,
delegate(*methods, to object)
delegate,
forward_missing_to(delegate)
forward_missing_to,
getter(*names, &block)
getter,
getter!(*names)
getter!,
getter?(*names, &block)
getter?,
property(*names, &block)
property,
property!(*names)
property!,
property?(*names, &block)
property?,
setter(*names)
setter
Class Method Detail
Resolves a domain that best matches the given options.
- domain may be an IP address or a domain name.
- service may be a port number or a service name. It must be specified,
because different servers may handle the
mailorhttpservices for example. - family is optional and defaults to
Family::UNSPEC - type is the intended socket type (e.g.
Type::STREAM) and must be specified. - protocol is the intended socket protocol (e.g.
Protocol::TCP) and should be specified. - timeout is optional and specifies the maximum time to wait before
IO::TimeoutErroris raised. Currently this is only supported on Windows.
Example:
require "socket"
addrinfos = Socket::Addrinfo.resolve("example.org", "http", type: Socket::Type::STREAM, protocol: Socket::Protocol::TCP)Resolves a domain that best matches the given options.
Yields each possible Addrinfo resolution since a domain may resolve to
many IP. Implementations are supposed to try all the addresses until the
socket is connected (or bound) or there are no addresses to try anymore.
Raising is an expensive operation, so instead of raising on a connect or bind error, just to rescue it immediately after, the block is expected to return the error instead, which will be raised once there are no more addresses to try.
The iteration will be stopped once the block returns something that isn't
an Exception (e.g. a Socket or nil).
Resolves domain for the TCP protocol and returns an Array of possible
Addrinfo. See #resolve for details.
Example:
require "socket"
addrinfos = Socket::Addrinfo.tcp("example.org", 80)Resolves a domain for the TCP protocol with STREAM type, and yields each
possible Addrinfo. See #resolve for details.
Resolves domain for the UDP protocol and returns an Array of possible
Addrinfo. See #resolve for details.
Example:
require "socket"
addrinfos = Socket::Addrinfo.udp("example.org", 53)Resolves a domain for the UDP protocol with DGRAM type, and yields each
possible Addrinfo. See #resolve for details.
Instance Method Detail
Appends this struct's name and instance variables names and values to the given IO.
struct Point
def initialize(@x : Int32, @y : Int32)
end
end
p1 = Point.new 1, 2
p1.to_s # "Point(@x=1, @y=2)"
p1.inspect # "Point(@x=1, @y=2)"