add simple yaml config

README.md

@@ -6,6 +6,7 @@ Rudimentary go chat server as a fun project.
 
 ```bash
 git clone https://git.coolaj86.com/coolaj86/chat.go.git
+go get gopkg.in/yaml.v2
 ```
 
 # Usage

chatserver.go

@@ -8,13 +8,24 @@ import (
   "flag"
   "fmt"
   "io"
+  "io/ioutil"
   "net"
   "os"
   "strconv"
   "sync"
   "time"
+
+  "gopkg.in/yaml.v2"
 )
 
+type Conf struct {
+  Port uint `yaml:"port,omitempty"`
+  Mailer struct {
+    ApiKey string `yaml:"api_key,omitempty"`
+    From string `yaml:"from,omitempty"`
+  }
+}
+
 type bufferedConn struct {
 	r    *bufio.Reader
 	rout io.Reader
@@ -61,6 +72,13 @@ func usage() {
 }
 
 func handleRaw(conn bufferedConn) {
+  // TODO
+  // What happens if this is being read from range
+  // when it's being added here (data race)?
+  // Should I use a channel here instead?
+  // TODO see https://jameshfisher.com/2017/04/18/golang-tcp-server.html
+  myRawConns[conn] = true
+
   // Handle all subsequent packets
   buf := make([]byte, 1024)
   for {
@@ -179,16 +197,35 @@ func handleConnection(conn net.Conn) {
 }
 
 func main() {
+  flag.Usage = usage
+  port := flag.Uint("telnet-port", 0, "tcp telnet chat port")
+  confname := flag.String("config", "./config.yml", "ymal config file")
+  flag.Parse()
+
+  var config Conf
+  confstr, err := ioutil.ReadFile(*confname)
+  fmt.Fprintf(os.Stdout, "-config=%s\n", *confname)
+  if nil != err {
+    fmt.Fprintf(os.Stderr, "%s\nUsing defaults instead\n", err)
+    confstr = []byte("{\"port\":" + strconv.Itoa(int(*port)) + "}")
+  }
+  err = yaml.Unmarshal(confstr, &config)
+  if nil != err {
+    config = Conf{}
+  }
+
   firstMsgs = make(chan myMsg, 128)
   myMsgs = make(chan myMsg, 128)
   newConns = make(chan net.Conn, 128)
   myRawConns = make(map[net.Conn]bool)
   myUnsortedConns = make(map[net.Conn]bool)
-  flag.Usage = usage
-  port:= flag.Uint("telnet-port", 4080, "tcp telnet chat port")
-  flag.Parse()
-  addr := ":" + strconv.Itoa(int(*port))
 
+  var addr string
+  if 0 != int(*port) {
+    addr = ":" + strconv.Itoa(int(*port))
+  } else {
+    addr = ":" + strconv.Itoa(int(config.Port))
+  }
 
   // https://golang.org/pkg/net/#Conn
   sock, err := net.Listen("tcp", addr)
@@ -213,6 +250,8 @@ func main() {
   for {
     select {
     case conn := <- newConns:
+      ts := time.Now()
+      fmt.Fprintf(os.Stdout, "[Handle New Connection] [Timestamp] %s\n", ts)
       go handleConnection(conn)
     case msg := <- myMsgs:
       ts, err := msg.receivedAt.MarshalJSON()

config.sample.yml

@@ -0,0 +1,4 @@
+port: 4080
+mailer:
+  api_key: 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'
+  from: 'mailer@example.com'