#
# Lazy Pirate client
# Use zmq_poll to do a safe request-reply
# To run, start lpserver and then randomly kill/restart it
#
package require zmq
set REQUEST_TIMEOUT 2500 ;# msecs, (> 1000!)
set REQUEST_RETRIES 3 ;# Before we abandon
set SERVER_ENDPOINT "tcp://localhost:5555"
zmq context context
puts "I: connecting to server…"
zmq socket client context REQ
client connect $SERVER_ENDPOINT
set sequence 0
set retries_left $REQUEST_RETRIES
while {$retries_left} {
# We send a request, then we work to get a reply
client send [incr sequence]
set expect_reply 1
while {$expect_reply} {
# Poll socket for a reply, with timeout
set rpoll_set [zmq poll client {POLLIN} $REQUEST_TIMEOUT]
# If we got a reply, process it
if {[llength $rpoll_set] && [lindex $rpoll_set 0 0] eq "client"} {
# We got a reply from the server, must match sequence
set reply [client recv]
if {$reply eq $sequence} {
puts "I: server replied OK ($reply)"
set retries_left $REQUEST_RETRIES
set expect_reply 0
} else {
puts "E: malformed reply from server: $reply"
}
} elseif {[incr retries_left -1] <= 0} {
puts "E: server seems to be offline, abandoning"
set retries_left 0
break
} else {
puts "W: no response from server, retrying…"
# Old socket is confused; close it and open a new one
client close
puts "I: connecting to server…"
zmq socket client context REQ
client connect $SERVER_ENDPOINT
# Send request again, on new socket
client send $sequence
}
}
}
client close
context term