use a Logger and disable it in specs

spec/amqproxy_spec.cr

@@ -2,13 +2,15 @@ require "./spec_helper"
 
 describe AMQProxy::Server do
   it "keeps connections open" do
-    s = AMQProxy::Server.new("127.0.0.1", 5672, false)
+    s = AMQProxy::Server.new("127.0.0.1", 5672, false, Logger::ERROR)
     spawn { s.listen("127.0.0.1", 5673) }
     sleep 0.001
-    AMQP::Connection.start(AMQP::Config.new(port: 5673)) do |conn|
-      conn.channel
-      s.client_connections.should eq(1)
-      s.upstream_connections.should eq(1)
+    10.times do
+      AMQP::Connection.start(AMQP::Config.new(port: 5673)) do |conn|
+        conn.channel
+        s.client_connections.should eq(1)
+        s.upstream_connections.should eq(1)
+      end
     end
     s.client_connections.should eq(0)
     s.upstream_connections.should eq(1)

src/amqproxy/client.cr

@@ -19,7 +19,6 @@ module AMQProxy
         @outbox.send frame
       end
     rescue ex : Errno | IO::Error | OpenSSL::SSL::Error
-      #print "Decoding client frames ", ex.inspect_with_backtrace, "\n"
       @outbox.send nil
     end
 
@@ -35,7 +34,6 @@ module AMQProxy
         @outbox.send nil
       end
     rescue ex : Errno | IO::Error | OpenSSL::SSL::Error
-      puts "Client conn closed: #{ex.message}"
       @outbox.send nil
     end
 

src/amqproxy/pool.cr

@@ -1,7 +1,7 @@
 module AMQProxy
   class Pool
     getter :size
-    def initialize(@host : String, @port : Int32, @tls : Bool)
+    def initialize(@host : String, @port : Int32, @tls : Bool, @log : Logger)
       @pools = {} of String => Deque(Upstream)
       @size = 0
     end
@@ -10,16 +10,16 @@ module AMQProxy
       q = @pools[[user, password, vhost].join] ||= Deque(Upstream).new
       u = q.shift do
         @size += 1
-        Upstream.new(@host, @port, @tls).connect(user, password, vhost)
+        Upstream.new(@host, @port, @tls, @log).connect(user, password, vhost)
       end
       block.call u
     ensure
       if u.nil?
         @size -= 1
-        print "Upstream connection could not be established\n"
+        @log.error "Upstream connection could not be established"
       elsif u.closed?
         @size -= 1
-        print "Upstream connection closed when returned\n"
+        @log.error "Upstream connection closed when returned"
       elsif !q.nil?
         q.push u
       end

src/amqproxy/server.cr

@@ -1,5 +1,6 @@
 require "socket"
 require "openssl"
+require "logger"
 require "./amqp"
 require "./pool"
 require "./client"
@@ -9,12 +10,15 @@ module AMQProxy
   class Server
     @running = true
 
-    def initialize(upstream_host, upstream_port, upstream_tls)
-      print "Proxy upstream: #{upstream_host}:#{upstream_port} "
-      print "TLS" if upstream_tls
-      print "\n"
-      @pool = Pool.new(upstream_host, upstream_port, upstream_tls)
+    def initialize(upstream_host, upstream_port, upstream_tls, log_level = Logger::INFO)
+      @log = Logger.new(STDOUT)
+      @log.level = log_level
+      @log.formatter = Logger::Formatter.new do |severity, datetime, progname, message, io|
+        io << message
+      end
       @client_connections = 0
+      @pool = Pool.new(upstream_host, upstream_port, upstream_tls, @log)
+      @log.info "Proxy upstream: #{upstream_host}:#{upstream_port} #{upstream_tls ? "TLS" : ""}"
     end
 
     getter :client_connections
@@ -31,7 +35,7 @@ module AMQProxy
         socket.tcp_keepalive_idle = 60
         socket.tcp_keepalive_count = 3
         socket.tcp_keepalive_interval = 10
-        puts "Proxy listening on #{socket.local_address}"
+        @log.info "Proxy listening on #{socket.local_address}"
         while @running
           if client = socket.accept?
             spawn handle_connection(client, client.remote_address)
@@ -53,17 +57,16 @@ module AMQProxy
         context = OpenSSL::SSL::Context::Server.new
         context.private_key = key_path
         context.certificate_chain = cert_path
-        puts "Proxy listening on #{socket.local_address}:#{port} (TLS)"
+        log.info "Proxy listening on #{socket.local_address}:#{port} (TLS)"
 
         while @running
           if client = @socket.accept?
-            print "Client connection accepted from ", client.remote_address, "\n"
             begin
               ssl_client = OpenSSL::SSL::Socket::Server.new(client, context)
               ssl_client.sync_close = ssl_client.sync = true
               spawn handle_connection(ssl_client, client.remote_address)
             rescue e : OpenSSL::SSL::Error
-              print "Error accepting OpenSSL connection from ", client.remote_address, ": ", e.message, "\n"
+              @log.error "Error accepting OpenSSL connection from #{client.remote_address}: #{e.inspect}"
             end
           else
             break
@@ -79,7 +82,7 @@ module AMQProxy
     def handle_connection(socket, remote_address)
       @client_connections += 1
       c = Client.new(socket)
-      print "Client connection accepted from ", remote_address, "\n"
+      @log.info { "Client connection accepted from #{remote_address}" }
       @pool.borrow(c.user, c.password, c.vhost) do |u|
         if u.nil?
           c.write AMQP::Connection::Close.new(403_u16, "ACCESS_REFUSED",
@@ -106,10 +109,9 @@ module AMQProxy
         end
       end
     rescue ex : Errno | IO::Error | OpenSSL::SSL::Error
-      print "Client connection error from ", remote_address, ": ",
-        ex.inspect_with_backtrace, "\n"
+      @log.debug { "Client connection error from #{remote_address}: #{ex.inspect}" }
     ensure
-      print "Client connection closed from ", remote_address, "\n"
+      @log.info { "Client connection closed from #{remote_address}" }
       socket.close
       @client_connections -= 1
     end

src/amqproxy/upstream.cr

@@ -4,7 +4,7 @@ require "uri"
 
 module AMQProxy
   class Upstream
-    def initialize(@host : String, @port : Int32, @tls : Bool)
+    def initialize(@host : String, @port : Int32, @tls : Bool, @log : Logger)
       @socket = uninitialized IO
       @to_client = Channel(AMQP::Frame?).new(1)
       @open_channels = Set(UInt16).new
@@ -14,7 +14,7 @@ module AMQProxy
     def connect(user : String, password : String, vhost : String)
       tcp_socket = TCPSocket.new(@host, @port)
       tcp_socket.tcp_nodelay = true
-      print "Connected to upstream ", tcp_socket.remote_address, "\n"
+      @log.info { "Connected to upstream #{tcp_socket.remote_address}" }
       @socket =
         if @tls
           OpenSSL::SSL::Socket::Client.new(tcp_socket, hostname: @host).tap do |c|
@@ -27,8 +27,7 @@ module AMQProxy
       spawn decode_frames
       self
     rescue ex : IO::EOFError
-      puts "Upstream connection failed to #{user}@#{@host}:#{@port}/#{vhost}"
-      ex.inspect_with_backtrace(STDERR)
+      @log.error "Failed connecting to upstream #{user}@#{@host}:#{@port}/#{vhost}"
       nil
     end
 
@@ -46,7 +45,7 @@ module AMQProxy
         @to_client.send frame
       end
     rescue ex : Errno | IO::EOFError
-      print "Error on upstream socket: ", ex.inspect, "\n"
+      @log.error "Error reading from upstream: #{ex.inspect}"
       @to_client.send nil
     end
 
@@ -83,7 +82,7 @@ module AMQProxy
       end
       @socket.write frame.to_slice
     rescue ex : Errno | IO::EOFError
-      puts "proxy write bytes: #{ex.message}"
+      @log.error "Error sending to upstream: #{ex.inspect}"
       @to_client.send nil
     end