feat: reconnect on disconnect (add status to TUI)

- add `Connected()` method for client
- add `LastErr` field to GoTomatoClient
  - replace error logging by updating `LastErr` field
  - modify methods to use pointer receivers for Client
- add `prevMessage` variable to store the last received server message
- show connect status in TUI
- use EnterAltScreen instead of ClearScreen

cmd/client/app.go

@@ -49,10 +49,14 @@ func (a app) waitForChannelSignal() tea.Cmd {
 func (a app) Init() tea.Cmd {
 	client = websocket.Connect(config.URL)
 	client.Password = config.Password
+	if client.LastErr != nil {
+		helper.Logger.Fatal(client.LastErr)
+	}
+
 	go client.ProcessServerMessages(a.channel)
 
 	return tea.Batch(
-		tea.ClearScreen,
+		tea.EnterAltScreen,
 		a.waitForChannelSignal(),
 	)
 }

cmd/client/view.go

@@ -3,22 +3,29 @@ package client
 import (
 	"strings"
 
+	"github.com/alecthomas/colour"
+
 	"git.smsvc.net/pomodoro/ChronoTomato/cmd/client/helper"
 	GoTomato "git.smsvc.net/pomodoro/GoTomato/pkg/models"
 )
 
 func (a app) View() string {
 	var body string
+	var serverStatus string
 
+	body = "Waiting for server message..."
 	if a.pomodoro != (GoTomato.ServerMessage{}) {
 		body = helper.TerminalOutput(a.pomodoro)
 		helper.DesktopNotifications(a.pomodoro)
-	} else {
-		body = "Waiting for first server message..."
+	}
+
+	serverStatus = colour.Sprintf("^D^1disconnected: %v^R\n", client.LastErr)
+	if client.Connected() {
+		serverStatus = colour.Sprintf("^D^2connected to %s^R\n", client.Server)
 	}
 
 	helpView := a.help.View(a.keys)
-	height := 8 - strings.Count(body, "\n") - strings.Count(helpView, "\n")
+	height := 8 - strings.Count(body, "\n") - strings.Count(serverStatus, "\n") - strings.Count(helpView, "\n")
 
-	return body + strings.Repeat("\n", height) + helpView
+	return body + strings.Repeat("\n", height) + serverStatus + helpView
 }

internal/websocket/connect.go

@@ -4,7 +4,6 @@ import (
 	"github.com/gorilla/websocket"
 	"time"
 
-	"git.smsvc.net/pomodoro/ChronoTomato/internal/helper"
 	ChronoTomato "git.smsvc.net/pomodoro/ChronoTomato/pkg/models"
 )
 
@@ -13,30 +12,24 @@ type Client ChronoTomato.GoTomatoClient // New websocket client
 // Connects to websocket
 func Connect(url string) Client {
 	conn, _, err := websocket.DefaultDialer.Dial(url, nil)
-	if err != nil {
-		helper.Logger.Fatal("Dial error!", "reason", err)
+
+	return Client{Conn: conn, Server: url, LastErr: err}
 }
 
-	helper.Logger.Info("Connected 󰖟 ", "host", url)
-	time.Sleep(time.Second)
-
-	return Client{Conn: conn}
+func (c Client) Connected() bool {
+	return c.Conn != nil
 }
 
 // Disconnects from websocket
 func (c Client) Disconnect() {
-	select {
-	case <-Done:
-		// session closed by remote
-		return
-	default:
 	// Cleanly close the connection by sending a close message and then
 	// waiting (with timeout) for the server to close the connection.
+	if c.Connected() {
 		c.Conn.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
 		select {
 		case <-Done:
 		case <-time.After(time.Second):
 		}
+	}
 	return
 }
-}

internal/websocket/receive.go

@@ -2,9 +2,10 @@ package websocket
 
 import (
 	"encoding/json"
+	"time"
+
 	"github.com/gorilla/websocket"
 
-	"git.smsvc.net/pomodoro/ChronoTomato/internal/helper"
 	GoTomato "git.smsvc.net/pomodoro/GoTomato/pkg/models"
 )
 
@@ -12,30 +13,35 @@ var Done = make(chan struct{})
 
 // Receives websocket messages and writes them to a channel.
 // Closes the channel if websocket closes.
-func (c Client) ProcessServerMessages(channel chan<- GoTomato.ServerMessage) {
-	var serverMessage GoTomato.ServerMessage
+func (c *Client) ProcessServerMessages(channel chan<- GoTomato.ServerMessage) {
+	var serverMessage, prevMessage GoTomato.ServerMessage
 
 	defer close(Done)
 
 	for {
 		_, message, err := c.Conn.ReadMessage()
 		if err != nil {
+			// On normal closure exit gracefully
 			if websocket.IsCloseError(err, websocket.CloseNormalClosure) {
-				// Ignore normal closure and exit gracefully
-				return
-			}
-			// Log any other errors
-			helper.Logger.Error("Read error!", "reason", err)
-			close(channel)
 				return
 			}
 
-		err = json.Unmarshal(message, &serverMessage)
-		if err != nil {
-			helper.Logger.Error("Error unmarshalling!", "reason", err)
+			// Try to reconnect on unexpected disconnect
+			for {
+				channel <- prevMessage // send previous ServerMessage to update view
+				time.Sleep(time.Second)
+				*c = Connect(c.Server)
+				if c.Connected() {
+					break
+				}
+			}
 			continue
 		}
 
+		err = json.Unmarshal(message, &serverMessage)
+		c.LastErr = err
+
 		channel <- serverMessage
+		prevMessage = serverMessage
 	}
 }

internal/websocket/send.go

@@ -4,27 +4,30 @@ import (
 	"encoding/json"
 	"github.com/gorilla/websocket"
 
-	"git.smsvc.net/pomodoro/ChronoTomato/internal/helper"
 	GoTomato "git.smsvc.net/pomodoro/GoTomato/pkg/models"
 )
 
 // Sends a message to the clients websocket
-func sendClientCommand(c Client, msg GoTomato.ClientCommand) {
+func sendClientCommand(c *Client, msg GoTomato.ClientCommand) {
+	if !c.Connected() {
+		// noop if client is not connected
+		return
+	}
 	messageBytes, err := json.Marshal(msg)
 	if err != nil {
-		helper.Logger.Error("Error marshalling!", "reason", err)
+		c.LastErr = err
 		return
 	}
 
 	err = c.Conn.WriteMessage(websocket.TextMessage, messageBytes)
 	if err != nil {
-		helper.Logger.Error("Write error!", "reason", err)
+		c.LastErr = err
 		return
 	}
 }
 
 // Sends the passed command to the server
-func (c Client) SendCmd(cmd string) {
+func (c *Client) SendCmd(cmd string) {
 	message := GoTomato.ClientCommand{
 		Command:  cmd,
 		Password: c.Password,
@@ -34,7 +37,7 @@ func (c Client) SendCmd(cmd string) {
 }
 
 // Sends the new PomodoroConfig to the server
-func (c Client) SendSettingsUpdate(settings GoTomato.PomodoroConfig) {
+func (c *Client) SendSettingsUpdate(settings GoTomato.PomodoroConfig) {
 	message := GoTomato.ClientCommand{
 		Command:  "updateSettings",
 		Password: c.Password,

pkg/models/client.go

@@ -4,6 +4,8 @@ import "github.com/gorilla/websocket"
 
 // Represents a GoTomato client
 type GoTomatoClient struct {
-	Conn     *websocket.Conn // The websocket connection of the client
+	Server   string          // The GoTomato server
 	Password string          // Pomodoro password
+	Conn     *websocket.Conn // The websocket connection of the client
+	LastErr  error           // Last client error
 }