From 950aeda87ee662a12c6e0a587ebc2a6c87dc1404 Mon Sep 17 00:00:00 2001
From: Jordan Orelli <jordanorelli@gmail.com>
Date: Sun, 25 Oct 2020 16:21:52 +0000
Subject: [PATCH] connection closing

---
 client.go | 36 +++++++++++++++++++++++++++---------
 ui.go     | 18 +++++++++++++++---
 2 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/client.go b/client.go
index 0831a8a..426ddf4 100644
--- a/client.go
+++ b/client.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"net/url"
 	"strings"
@@ -16,7 +17,7 @@ type client struct {
 	port int
 }
 
-func (c *client) run() {
+func (c *client) run(ctx context.Context) {
 	dialer := websocket.Dialer{
 		HandshakeTimeout: 3 * time.Second,
 		ReadBufferSize:   32 * 1024,
@@ -41,15 +42,32 @@ func (c *client) run() {
 		c.Debug("dial response header: %s = %s", k, strings.Join(vals, ","))
 	}
 
+	tick := time.NewTicker(time.Second)
+	defer tick.Stop()
+
 	for {
-		w, err := conn.NextWriter(websocket.TextMessage)
-		if err != nil {
-			c.Error("unable to get a websocket frame writer: %v", err)
-			break
-		}
+		select {
+		case <-tick.C:
+			w, err := conn.NextWriter(websocket.TextMessage)
+			if err != nil {
+				c.Error("unable to get a websocket frame writer: %v", err)
+				break
+			}
 
-		w.Write([]byte("hey"))
-		w.Close()
-		time.Sleep(time.Second)
+			w.Write([]byte("hey"))
+			w.Close()
+		case <-ctx.Done():
+			c.Info("parent context done, sending close message")
+			msg := websocket.FormatCloseMessage(websocket.CloseNormalClosure, "")
+			if err := conn.WriteMessage(websocket.CloseMessage, msg); err != nil {
+				c.Error("failed to write close message: %v", err)
+			}
+			c.Info("closing connection")
+			if err := conn.Close(); err != nil {
+				c.Error("failed to close connection: %v", err)
+			}
+			c.Info("connection closed")
+			return
+		}
 	}
 }
diff --git a/ui.go b/ui.go
index 494c63f..d54f947 100644
--- a/ui.go
+++ b/ui.go
@@ -1,6 +1,9 @@
 package main
 
 import (
+	"context"
+	"time"
+
 	"github.com/gdamore/tcell/v2"
 	"github.com/jordanorelli/belt-mud/internal/exit"
 	"github.com/jordanorelli/blammo"
@@ -11,15 +14,25 @@ type ui struct {
 	*blammo.Log
 	screen tcell.Screen
 	mode   uiMode
+	client *client
 }
 
 func (ui *ui) run() {
-	c := client{
+	ui.client = &client{
 		Log:  ui.Child("client"),
 		host: "127.0.0.1",
 		port: 12805,
 	}
-	go c.run()
+	ctx := context.Background()
+
+	ctx, cancel := context.WithCancel(ctx)
+	defer func() {
+		ui.Debug("canceling client context")
+		cancel()
+		time.Sleep(time.Second)
+	}()
+
+	go ui.client.run(ctx)
 
 	screen, err := tcell.NewScreen()
 	if err != nil {
@@ -90,7 +103,6 @@ func (ui *ui) menu() {
 		}
 
 		ui.mode.HandleEvent(e)
-
 		ui.screen.Clear()
 		ui.mode.draw(ui)
 		ui.screen.Show()