From 797d8c92be3bbb20761cb899a402a39106da59e9 Mon Sep 17 00:00:00 2001
From: Andrey Petrov <andrey.petrov@shazow.net>
Date: Sun, 18 Jan 2015 22:05:49 -0800
Subject: [PATCH] --log file with timestamps

---
 chat/history.go | 30 ++++++++++++++++++++++++------
 chat/message.go |  5 +++++
 chat/room.go    |  6 ++++++
 cmd.go          | 14 +++++++++++++-
 4 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/chat/history.go b/chat/history.go
index 44513a6..6b999ca 100644
--- a/chat/history.go
+++ b/chat/history.go
@@ -1,13 +1,20 @@
 package chat
 
-import "sync"
+import (
+	"fmt"
+	"io"
+	"sync"
+)
+
+const timestampFmt = "2006-01-02 15:04:05"
 
 // History contains the history entries
 type History struct {
+	sync.RWMutex
 	entries []Message
 	head    int
 	size    int
-	lock    sync.Mutex
+	out     io.Writer
 }
 
 // NewHistory constructs a new history of the given size
@@ -19,8 +26,8 @@ func NewHistory(size int) *History {
 
 // Add adds the given entry to the entries in the history
 func (h *History) Add(entry Message) {
-	h.lock.Lock()
-	defer h.lock.Unlock()
+	h.Lock()
+	defer h.Unlock()
 
 	max := cap(h.entries)
 	h.head = (h.head + 1) % max
@@ -28,6 +35,10 @@ func (h *History) Add(entry Message) {
 	if h.size < max {
 		h.size++
 	}
+
+	if h.out != nil {
+		fmt.Fprintf(h.out, "[%s] %s\n", entry.Timestamp().UTC().Format(timestampFmt), entry.String())
+	}
 }
 
 // Len returns the number of entries in the history
@@ -37,8 +48,8 @@ func (h *History) Len() int {
 
 // Get the entry with the given number
 func (h *History) Get(num int) []Message {
-	h.lock.Lock()
-	defer h.lock.Unlock()
+	h.RLock()
+	defer h.RUnlock()
 
 	max := cap(h.entries)
 	if num > h.size {
@@ -56,3 +67,10 @@ func (h *History) Get(num int) []Message {
 
 	return r
 }
+
+// SetOutput sets the output for logging added messages
+func (h *History) SetOutput(w io.Writer) {
+	h.Lock()
+	h.out = w
+	h.Unlock()
+}
diff --git a/chat/message.go b/chat/message.go
index b4bfee5..9a0b30a 100644
--- a/chat/message.go
+++ b/chat/message.go
@@ -11,6 +11,7 @@ type Message interface {
 	Render(*Theme) string
 	String() string
 	Command() string
+	Timestamp() time.Time
 }
 
 type MessageTo interface {
@@ -61,6 +62,10 @@ func (m *Msg) Command() string {
 	return ""
 }
 
+func (m *Msg) Timestamp() time.Time {
+	return m.timestamp
+}
+
 // PublicMsg is any message from a user sent to the room.
 type PublicMsg struct {
 	Msg
diff --git a/chat/room.go b/chat/room.go
index e6f68b5..041fe9e 100644
--- a/chat/room.go
+++ b/chat/room.go
@@ -3,6 +3,7 @@ package chat
 import (
 	"errors"
 	"fmt"
+	"io"
 	"sync"
 )
 
@@ -59,6 +60,11 @@ func (r *Room) Close() {
 	})
 }
 
+// SetLogging sets logging output for the room's history
+func (r *Room) SetLogging(out io.Writer) {
+	r.history.SetOutput(out)
+}
+
 // HandleMsg reacts to a message, will block until done.
 func (r *Room) HandleMsg(m Message) {
 	switch m := m.(type) {
diff --git a/cmd.go b/cmd.go
index 721c597..a342a02 100644
--- a/cmd.go
+++ b/cmd.go
@@ -28,6 +28,7 @@ type Options struct {
 	Admin     string `long:"admin" description:"File of public keys who are admins."`
 	Whitelist string `long:"whitelist" description:"Optional file of public keys who are allowed to connect."`
 	Motd      string `long:"motd" description:"Optional Message of the Day file."`
+	Log       string `long:"log" description:"Write chat log to this file."`
 	Pprof     int    `long:"pprof" description:"Enable pprof http server for profiling."`
 }
 
@@ -116,7 +117,7 @@ func main() {
 			return err
 		}
 		auth.Op(key)
-		logger.Debugf("Added admin: %s", line)
+		logger.Debugf("Added admin: %s", sshd.Fingerprint(key))
 		return nil
 	})
 	if err != nil {
@@ -151,6 +152,17 @@ func main() {
 		host.SetMotd(motdString)
 	}
 
+	if options.Log == "-" {
+		host.SetLogging(os.Stdout)
+	} else if options.Log != "" {
+		fp, err := os.OpenFile(options.Log, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+		if err != nil {
+			logger.Errorf("Failed to open log file for writing: %v", err)
+			return
+		}
+		host.SetLogging(fp)
+	}
+
 	go host.Serve()
 
 	// Construct interrupt handler