A RingServer
allows a Rinda::TupleSpace
to be located via UDP broadcasts. Default service location uses the following steps:
-
A
RingServer
begins listening on the network broadcast UDP address. -
A
RingFinger
sends a UDP packet containing theDRb
URI
where it will listen for a reply. -
The
RingServer
receives the UDP packet and connects back to the providedDRb
URI
with theDRb
service.
A RingServer
requires a TupleSpace:
ts = Rinda::TupleSpace.new rs = Rinda::RingServer.new
RingServer
can also listen on multicast addresses for announcements. This allows multiple RingServers to run on the same host. To use network broadcast and multicast:
ts = Rinda::TupleSpace.new rs = Rinda::RingServer.new ts, %w[Socket::INADDR_ANY, 239.0.0.1 ff02::1]
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 94
def initialize(ts, addresses=[Socket::INADDR_ANY], port=Ring_PORT)
@port = port
if Integer === addresses then
addresses, @port = [Socket::INADDR_ANY], addresses
end
@renewer = Renewer.new
@ts = ts
@sockets = []
addresses.each do |address|
if Array === address
make_socket(*address)
else
make_socket(address)
end
end
@w_services = write_services
@r_service = reply_service
end
Advertises ts
on the given addresses
at port
.
If addresses
is omitted only the UDP broadcast address is used.
addresses
can contain multiple addresses. If a multicast address is given in addresses
then the RingServer
will listen for multicast queries.
If you use IPv4 multicast you may need to set an address of the inbound interface which joins a multicast group.
ts = Rinda::TupleSpace.new rs = Rinda::RingServer.new(ts, [['239.0.0.1', '9.5.1.1']])
You can set addresses as an Array
Object
. The first element of the Array
is a multicast address and the second is an inbound interface address. If the second is omitted then ‘0.0.0.0’ is used.
If you use IPv6 multicast you may need to set both the local interface address and the inbound interface index:
rs = Rinda::RingServer.new(ts, [['ff02::1', '::1', 1]])
The first element is a multicast address and the second is an inbound interface address. The third is an inbound interface index.
At this time there is no easy way to get an interface index by name.
If the second is omitted then ‘::1’ is used. If the third is omitted then 0 (default interface) is used.
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 218
def do_reply
tuple = @ts.take([:lookup_ring, nil], @renewer)
Thread.new { tuple[1].call(@ts) rescue nil}
rescue
end
Pulls lookup tuples out of the TupleSpace
and sends their DRb
object the address of the local TupleSpace
.
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 193
def do_write(msg)
Thread.new do
begin
tuple, sec = Marshal.load(msg)
@ts.write(tuple, sec)
rescue
end
end
end
Extracts the response URI
from msg
and adds it to TupleSpace
where it will be picked up by reply_service
for notification.
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 132
def make_socket(address, interface_address=nil, multicast_interface=0)
addrinfo = Addrinfo.udp(address, @port)
socket = Socket.new(addrinfo.pfamily, addrinfo.socktype,
addrinfo.protocol)
if addrinfo.ipv4_multicast? or addrinfo.ipv6_multicast? then
if Socket.const_defined?(:SO_REUSEPORT) then
socket.setsockopt(:SOCKET, :SO_REUSEPORT, true)
else
socket.setsockopt(:SOCKET, :SO_REUSEADDR, true)
end
if addrinfo.ipv4_multicast? then
interface_address = '0.0.0.0' if interface_address.nil?
socket.bind(Addrinfo.udp(interface_address, @port))
mreq = IPAddr.new(addrinfo.ip_address).hton +
IPAddr.new(interface_address).hton
socket.setsockopt(:IPPROTO_IP, :IP_ADD_MEMBERSHIP, mreq)
else
interface_address = '::1' if interface_address.nil?
socket.bind(Addrinfo.udp(interface_address, @port))
mreq = IPAddr.new(addrinfo.ip_address).hton +
[multicast_interface].pack('I')
socket.setsockopt(:IPPROTO_IPV6, :IPV6_JOIN_GROUP, mreq)
end
else
socket.bind(addrinfo)
end
socket
rescue
socket = socket.close if socket
raise
ensure
@sockets << socket if socket
end
Creates a socket at address
If address
is multicast address then interface_address
and multicast_interface
can be set as optional.
A created socket is bound to interface_address
. If you use IPv4 multicast then the interface of interface_address
is used as the inbound interface. If interface_address
is omitted or nil then ‘0.0.0.0’ or ‘::1’ is used.
If you use IPv6 multicast then multicast_interface
is used as the inbound interface. multicast_interface
is a network interface index. If multicast_interface
is omitted then 0 (default interface) is used.
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 206
def reply_service
Thread.new do
loop do
do_reply
end
end
end
Creates a thread that notifies waiting clients from the TupleSpace
.
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 227
def shutdown
@renewer.renew = false
@w_services.each do |thread|
thread.kill
thread.join
end
@sockets.each do |socket|
socket.close
end
@r_service.kill
@r_service.join
end
Shuts down the RingServer
# File tmp/rubies/ruby-2.7.6/lib/rinda/ring.rb, line 178
def write_services
@sockets.map do |s|
Thread.new(s) do |socket|
loop do
msg = socket.recv(1024)
do_write(msg)
end
end
end
end
Creates threads that pick up UDP packets and passes them to do_write
for decoding.