environment/lib/package/daemon.rb

121 lines
3.1 KiB
Ruby

require 'ffi-rzmq'
require 'json'
require 'time' # for Time#iso8601
# $LOAD_PATH.unshift(File.expand_path("../lib", __dir__)) # <<< add this line
# require "package"
def start_daemon(endpoint)
# Clean up stale ipc file (bind will fail otherwise)
begin
path = ENDPOINT.sub("ipc://", "")
File.unlink(path) if File.exist?(path)
rescue => e
warn "Cleanup failed: #{e.message}"
end
ctx = ZMQ::Context.new
rep = ctx.socket(ZMQ::REP)
rc = rep.bind(endpoint)
abort "bind failed: #{ZMQ::Util.error_string}" unless rc == 0
puts "RPC server on #{endpoint}"
# Define RPC methods (use a local variable, not a constant)
rpc_methods = {
"echo" => ->(params) { params }, # returns whatever you send
"add" => ->(params) { Array(params).map(&:to_f).sum }, # add numbers
"time" => ->(_params) { Time.now.utc.iso8601 } # current time
}
ok = ->(id, result) { { "jsonrpc"=>"2.0", "id"=>id, "result"=>result }.to_json }
err = ->(id, code, msg, data=nil) do
body = { "jsonrpc"=>"2.0", "id"=>id, "error"=>{ "code"=>code, "message"=>msg } }
body["error"]["data"] = data unless data.nil?
body.to_json
end
shutdown = proc do
begin
rep.close
ensure
ctx.terminate
end
puts "\nbye"
begin
path = endpoint.sub("ipc://", "")
File.unlink(path) if File.exist?(path)
rescue; end
puts "\nbye"
exit
end
trap("INT") { shutdown.call }
trap("TERM") { shutdown.call }
loop do
# raw = ''
# next unless rep.recv_string(raw) == 0
# puts raw
raw = ''
rc = rep.recv_string(raw)
puts "[server] recv rc=#{rc} raw=#{raw.inspect}"
#next unless rc == 0
if rc == -1
errno = ZMQ::Util.errno
warn "[server] recv error #{errno}: #{ZMQ::Util.error_string}"
case errno
when ZMQ::EINTR
next # interrupted by signal; retry
when ZMQ::ETERM
break # context shutting down
when ZMQ::EFSM
# Socket in wrong state (likely previous send failed).
# Reset the REP socket.
rep.close
rep = ctx.socket(ZMQ::REP)
rep.setsockopt(ZMQ::LINGER, 0)
rep.bind(ENDPOINT)
next
else
sleep 0.01 # avoid hot loop on unexpected errors
next
end
end
begin
req = JSON.parse(raw)
id = req["id"]
meth = req["method"]
params = req["params"]
if req["jsonrpc"] != "2.0"
rep.send_string(err.call(id, -32600, "Invalid Request: jsonrpc must be '2.0'"))
next
end
handler = rpc_methods[meth]
unless handler
rep.send_string(err.call(id, -32601, "Method not found: #{meth}"))
next
end
result = handler.call(params)
rep.send_string(ok.call(id, result))
rescue JSON::ParserError => e
rep.send_string(err.call(nil, -32700, "Parse error", e.message))
rescue => e
rep.send_string(err.call(nil, -32000, "Server error", e.message))
end
end
end