server: -netdebug flag now controls tracing for #90

Network trace is sent to stdout, no longer part of normal debug
logging.

cmd/inbucket/main.go

@@ -59,6 +59,7 @@ func main() {
 	pidfile := flag.String("pidfile", "", "Write our PID into the specified file.")
 	logfile := flag.String("logfile", "stderr", "Write out log into the specified file.")
 	logjson := flag.Bool("logjson", false, "Logs are written in JSON format.")
+	netdebug := flag.Bool("netdebug", false, "Dump SMTP & POP3 network traffic to stdout.")
 	flag.Usage = func() {
 		fmt.Fprintln(os.Stderr, "Usage: inbucket [options]")
 		flag.PrintDefaults()
@@ -89,6 +90,10 @@ func main() {
 		fmt.Fprintf(os.Stderr, "Configuration error: %v\n", err)
 		os.Exit(1)
 	}
+	if *netdebug {
+		conf.POP3.Debug = true
+		conf.SMTP.Debug = true
+	}
 	// Setup signal handler.
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGINT)

pkg/config/config.go

@@ -45,6 +45,7 @@ type SMTP struct {
 	MaxMessageBytes int           `required:"true" default:"10240000" desc:"Maximum message size"`
 	StoreMessages   bool          `required:"true" default:"true" desc:"Store incoming mail?"`
 	Timeout         time.Duration `required:"true" default:"300s" desc:"Idle network timeout"`
+	Debug           bool          `ignored:"true"`
 }
 
 // POP3 contains the POP3 server configuration.
@@ -52,6 +53,7 @@ type POP3 struct {
 	Addr    string        `required:"true" default:"0.0.0.0:1100" desc:"POP3 server IP4 host:port"`
 	Domain  string        `required:"true" default:"inbucket" desc:"HELLO domain"`
 	Timeout time.Duration `required:"true" default:"600s" desc:"Idle network timeout"`
+	Debug   bool          `ignored:"true"`
 }
 
 // Web contains the HTTP server configuration.

pkg/server/pop3/handler.go

@@ -2,7 +2,6 @@ package pop3
 
 import (
 	"bufio"
-	"bytes"
 	"fmt"
 	"io"
 	"net"
@@ -58,26 +57,35 @@ var commands = map[string]bool{
 
 // Session defines an active POP3 session
 type Session struct {
-	server     *Server           // Reference to the server we belong to
+	server     *Server           // Reference to the server we belong to.
-	id         int               // Session ID number
+	id         int               // Session ID number.
-	conn       net.Conn          // Our network connection
+	conn       net.Conn          // Our network connection.
-	remoteHost string            // IP address of client
+	remoteHost string            // IP address of client.
-	sendError  error             // Used to bail out of read loop on send error
+	sendError  error             // Used to bail out of read loop on send error.
-	state      State             // Current session state
+	state      State             // Current session state.
-	reader     *bufio.Reader     // Buffered reader for our net conn
+	reader     *bufio.Reader     // Buffered reader for our net conn.
-	user       string            // Mailbox name
+	user       string            // Mailbox name.
-	messages   []storage.Message // Slice of messages in mailbox
+	messages   []storage.Message // Slice of messages in mailbox.
-	retain     []bool            // Messages to retain upon UPDATE (true=retain)
+	retain     []bool            // Messages to retain upon UPDATE (true=retain).
-	msgCount   int               // Number of undeleted messages
+	msgCount   int               // Number of undeleted messages.
-	logger     zerolog.Logger
+	logger     zerolog.Logger    // Session specific logger.
+	debug      bool              // Print network traffic to stdout.
 }
 
 // NewSession creates a new POP3 session
 func NewSession(server *Server, id int, conn net.Conn, logger zerolog.Logger) *Session {
 	reader := bufio.NewReader(conn)
 	host, _, _ := net.SplitHostPort(conn.RemoteAddr().String())
-	return &Session{server: server, id: id, conn: conn, state: AUTHORIZATION,
+	return &Session{
-		reader: reader, remoteHost: host, logger: logger}
+		server:     server,
+		id:         id,
+		conn:       conn,
+		state:      AUTHORIZATION,
+		reader:     reader,
+		remoteHost: host,
+		logger:     logger,
+		debug:      server.config.Debug,
+	}
 }
 
 func (s *Session) String() string {
@@ -550,41 +558,12 @@ func (s *Session) send(msg string) {
 	}
 	if _, err := fmt.Fprint(s.conn, msg+"\r\n"); err != nil {
 		s.sendError = err
-		s.logger.Warn().Msgf("Failed to send: '%v'", msg)
+		s.logger.Warn().Msgf("Failed to send: %q", msg)
 		return
 	}
-	s.logger.Debug().Msgf(">> %v >>", msg)
+	if s.debug {
-}
+		fmt.Printf("%04d > %v\n", s.id, msg)
-
-// readByteLine reads a line of input into the provided buffer. Does
-// not reset the Buffer - please do so prior to calling.
-func (s *Session) readByteLine(buf *bytes.Buffer) error {
-	if err := s.conn.SetReadDeadline(s.nextDeadline()); err != nil {
-		return err
 	}
-	for {
-		line, err := s.reader.ReadBytes('\r')
-		if err != nil {
-			return err
-		}
-		if _, err = buf.Write(line); err != nil {
-			return err
-		}
-		// Read the next byte looking for '\n'
-		c, err := s.reader.ReadByte()
-		if err != nil {
-			return err
-		}
-		if err := buf.WriteByte(c); err != nil {
-			return err
-		}
-		if c == '\n' {
-			// We've reached the end of the line, return
-			return nil
-		}
-		// Else, keep looking
-	}
-	// Should be unreachable
 }
 
 // Reads a line of input
@@ -596,7 +575,9 @@ func (s *Session) readLine() (line string, err error) {
 	if err != nil {
 		return "", err
 	}
-	s.logger.Debug().Msgf("<< %v <<", strings.TrimRight(line, "\r\n"))
+	if s.debug {
+		fmt.Printf("%04d   %v\n", s.id, strings.TrimRight(line, "\r\n"))
+	}
 	return line, nil
 }
 

pkg/server/pop3/listener.go

@@ -13,6 +13,8 @@ import (
 
 // Server defines an instance of our POP3 server
 type Server struct {
+	// TODO(#91) Refactor config items out of this struct
+	config         config.POP3
 	host           string
 	domain         string
 	timeout        time.Duration
@@ -25,6 +27,7 @@ type Server struct {
 // New creates a new Server struct
 func New(cfg config.POP3, shutdownChan chan bool, store storage.Store) *Server {
 	return &Server{
+		config:         cfg,
 		host:           cfg.Addr,
 		domain:         cfg.Domain,
 		store:          store,

pkg/server/smtp/handler.go

@@ -80,7 +80,8 @@ type Session struct {
 	reader       *bufio.Reader
 	from         string
 	recipients   []*policy.Recipient
-	logger       zerolog.Logger
+	logger       zerolog.Logger // Session specific logger.
+	debug        bool           // Print network traffic to stdout.
 }
 
 // NewSession creates a new Session for the given connection
@@ -96,6 +97,7 @@ func NewSession(server *Server, id int, conn net.Conn, logger zerolog.Logger) *S
 		remoteHost: host,
 		recipients: make([]*policy.Recipient, 0),
 		logger:     logger,
+		debug:      server.config.Debug,
 	}
 }
 
@@ -433,7 +435,9 @@ func (s *Session) send(msg string) {
 		s.logger.Warn().Msgf("Failed to send: %q", msg)
 		return
 	}
-	s.logger.Debug().Msgf(">> %v >>", msg)
+	if s.debug {
+		fmt.Printf("%04d > %v\n", s.id, msg)
+	}
 }
 
 // readByteLine reads a line of input, returns byte slice.
@@ -441,7 +445,11 @@ func (s *Session) readByteLine() ([]byte, error) {
 	if err := s.conn.SetReadDeadline(s.nextDeadline()); err != nil {
 		return nil, err
 	}
-	return s.reader.ReadBytes('\n')
+	b, err := s.reader.ReadBytes('\n')
+	if err == nil && s.debug {
+		fmt.Printf("%04d   %s\n", s.id, bytes.TrimRight(b, "\r\n"))
+	}
+	return b, err
 }
 
 // Reads a line of input
@@ -453,7 +461,9 @@ func (s *Session) readLine() (line string, err error) {
 	if err != nil {
 		return "", err
 	}
-	s.logger.Debug().Msgf("<< %v <<", strings.TrimRight(line, "\r\n"))
+	if s.debug {
+		fmt.Printf("%04d   %v\n", s.id, strings.TrimRight(line, "\r\n"))
+	}
 	return line, nil
 }
 

pkg/server/smtp/listener.go

@@ -38,6 +38,8 @@ func init() {
 
 // Server holds the configuration and state of our SMTP server
 type Server struct {
+	// TODO(#91) Refactor config items out of this struct
+	config config.SMTP
 	// Configuration
 	host            string
 	domain          string
@@ -86,6 +88,7 @@ func NewServer(
 	apolicy *policy.Addressing,
 ) *Server {
 	return &Server{
+		config:          cfg,
 		host:            cfg.Addr,
 		domain:          cfg.Domain,
 		domainNoStore:   strings.ToLower(cfg.DomainNoStore),