cli: Separate UI logic and fix client threadsafety

cli/cli.go

@@ -3,13 +3,10 @@ package main
 import (
 	"fmt"
 	rpc "github.com/special/notricochet/rpc"
-	"golang.org/x/net/context"
 	"google.golang.org/grpc"
 	"gopkg.in/readline.v1"
 	"log"
 	"os"
-	"strconv"
-	"strings"
 )
 
 const (
@@ -32,108 +29,20 @@ func main() {
 	defer input.Close()
 	log.SetOutput(input.Stdout())
 
-	c := &Client{
+	client := &Client{
 		Backend: rpc.NewRicochetCoreClient(conn),
-		Input:   input,
 	}
+	ui := &UI{
+		Input:  input,
+		Client: client,
+	}
+	client.Ui = ui
 
-	if err := c.Initialize(); err != nil {
+	if err := client.Initialize(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
 
-	go c.Run()
+	go client.Run()
-
+	ui.CommandLoop()
-	input.SetPrompt("> ")
-	for {
-		line := input.Line()
-		if line.CanContinue() {
-			continue
-		} else if line.CanBreak() {
-			break
-		}
-
-		words := strings.SplitN(line.Line, " ", 1)
-
-		if id, err := strconv.Atoi(words[0]); err == nil {
-			contact := c.Contacts.ById(int32(id))
-			if contact != nil {
-				c.SetCurrentContact(contact)
-			} else {
-				fmt.Printf("no contact %d\n", id)
-			}
-			continue
-		}
-
-		if c.CurrentContact != nil {
-			if len(words[0]) > 0 && words[0][0] == '/' {
-				words[0] = words[0][1:]
-			} else {
-				_, err := c.Backend.SendMessage(context.Background(), &rpc.Message{
-					Sender: &rpc.Entity{IsSelf: true},
-					Recipient: &rpc.Entity{
-						ContactId: c.CurrentContact.Data.Id,
-						Address:   c.CurrentContact.Data.Address,
-					},
-					Text: line.Line,
-				})
-				if err != nil {
-					fmt.Printf("send message error: %v\n", err)
-				}
-				continue
-			}
-		}
-
-		switch words[0] {
-		case "clear":
-			readline.ClearScreen(readline.Stdout)
-
-		case "quit":
-			os.Exit(0)
-
-		case "status":
-			fmt.Printf("server: %v\n", c.ServerStatus)
-			fmt.Printf("identity: %v\n", c.Identity)
-
-		case "connect":
-			status, err := c.Backend.StartNetwork(context.Background(), &rpc.StartNetworkRequest{})
-			if err != nil {
-				fmt.Printf("start network error: %v\n", err)
-			} else {
-				fmt.Printf("network started: %v\n", status)
-			}
-
-		case "disconnect":
-			status, err := c.Backend.StopNetwork(context.Background(), &rpc.StopNetworkRequest{})
-			if err != nil {
-				fmt.Printf("stop network error: %v\n", err)
-			} else {
-				fmt.Printf("network stopped: %v\n", status)
-			}
-
-		case "contacts":
-			byStatus := make(map[rpc.Contact_Status][]*Contact)
-			for _, contact := range c.Contacts.Contacts {
-				byStatus[contact.Data.Status] = append(byStatus[contact.Data.Status], contact)
-			}
-
-			order := []rpc.Contact_Status{rpc.Contact_ONLINE, rpc.Contact_UNKNOWN, rpc.Contact_OFFLINE, rpc.Contact_REQUEST, rpc.Contact_REJECTED}
-			for _, status := range order {
-				contacts := byStatus[status]
-				if len(contacts) == 0 {
-					continue
-				}
-				fmt.Printf(". %s\n", strings.ToLower(status.String()))
-				for _, contact := range contacts {
-					fmt.Printf("... [%d] %s\n", contact.Data.Id, contact.Data.Nickname)
-				}
-			}
-
-		case "help":
-			fallthrough
-
-		default:
-			fmt.Println("Commands: clear, quit, status, connect, disconnect, contacts, help")
-		}
-	}
 }

cli/client.go

@@ -4,23 +4,22 @@ import (
 	"fmt"
 	"github.com/special/notricochet/rpc"
 	"golang.org/x/net/context"
-	"gopkg.in/readline.v1"
 	"log"
-	"strings"
 )
 
 type Client struct {
 	Backend ricochet.RicochetCoreClient
-	Input   *readline.Instance
+	Ui      *UI
 
 	ServerStatus ricochet.ServerStatusReply
 	Identity     ricochet.Identity
 
 	NetworkStatus ricochet.NetworkStatus
 	Contacts      *ContactList
-	CurrentContact *Contact
 
 	monitorsChannel   chan interface{}
+	blockChannel      chan struct{}
+	unblockChannel    chan struct{}
 	populatedContacts bool
 }
 
@@ -28,6 +27,8 @@ type Client struct {
 func (c *Client) Initialize() error {
 	c.Contacts = NewContactList()
 	c.monitorsChannel = make(chan interface{}, 10)
+	c.blockChannel = make(chan struct{})
+	c.unblockChannel = make(chan struct{})
 
 	// Query server status and version
 	status, err := c.Backend.GetServerStatus(context.Background(), &ricochet.ServerStatusRequest{
@@ -71,24 +72,18 @@ func (c *Client) Run() {
 			default:
 				log.Panicf("Unknown event type on monitor channel: %v", event)
 			}
+		case <-c.blockChannel:
+			<-c.unblockChannel
 		}
 	}
 }
 
-func (c *Client) SetCurrentContact(contact *Contact) {
+func (c *Client) Block() {
-	c.CurrentContact = contact
+	c.blockChannel <- struct{}{}
-	if c.CurrentContact != nil {
-		config := *c.Input.Config
-		config.Prompt = fmt.Sprintf("%s > ", c.CurrentContact.Data.Nickname)
-		config.UniqueEditLine = true
-		c.Input.SetConfig(&config)
-		fmt.Printf("--- %s (%s) ---\n", c.CurrentContact.Data.Nickname, strings.ToLower(c.CurrentContact.Data.Status.String()))
-	} else {
-		config := *c.Input.Config
-		config.Prompt = "> "
-		config.UniqueEditLine = false
-		c.Input.SetConfig(&config)
 }
+
+func (c *Client) Unblock() {
+	c.unblockChannel <- struct{}{}
 }
 
 func (c *Client) monitorNetwork() {
@@ -206,8 +201,8 @@ func (c *Client) onContactEvent(event *ricochet.ContactEvent) {
 
 		contact, _ := c.Contacts.Deleted(data)
 
-		if c.CurrentContact == contact {
+		if c.Ui.CurrentContact == contact {
-			c.SetCurrentContact(nil)
+			c.Ui.SetCurrentContact(nil)
 		}
 
 	default:
@@ -241,16 +236,7 @@ func (c *Client) onConversationEvent(event *ricochet.ConversationEvent) {
 		return
 	}
 
-	if remoteContact == c.CurrentContact {
+	c.Ui.PrintMessage(remoteContact, message.Sender.IsSelf, message.Text)
-		// XXX so unsafe
-		if message.Sender.IsSelf {
-			fmt.Fprintf(c.Input.Stdout(), "\r%s > %s\n", remoteContact.Data.Nickname, message.Text)
-		} else {
-			fmt.Fprintf(c.Input.Stdout(), "\r%s < %s\n", remoteContact.Data.Nickname, message.Text)
-		}
-	} else if !message.Sender.IsSelf {
-		fmt.Fprintf(c.Input.Stdout(), "\r---- %s < %s\n", remoteContact.Data.Nickname, message.Text)
-	}
 
 	if !message.Sender.IsSelf {
 		backend := c.Backend

cli/ui.go

@@ -0,0 +1,163 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"github.com/special/notricochet/rpc"
+	"golang.org/x/net/context"
+	"gopkg.in/readline.v1"
+	"strconv"
+	"strings"
+)
+
+type UI struct {
+	Input  *readline.Instance
+	Client *Client
+
+	CurrentContact *Contact
+}
+
+func (ui *UI) CommandLoop() {
+	ui.Input.SetPrompt("> ")
+	for {
+		line, err := ui.Input.Readline()
+		if err != nil {
+			return
+		}
+
+		if err := ui.Execute(line); err != nil {
+			return
+		}
+	}
+}
+
+func (ui *UI) Execute(line string) error {
+	// Block client event handlers for threadsafety
+	ui.Client.Block()
+	defer ui.Client.Unblock()
+
+	words := strings.SplitN(line, " ", 1)
+
+	if ui.CurrentContact != nil {
+		if len(words[0]) > 0 && words[0][0] == '/' {
+			words[0] = words[0][1:]
+		} else {
+			ui.SendMessage(line)
+			return nil
+		}
+	}
+
+	if id, err := strconv.Atoi(words[0]); err == nil {
+		contact := ui.Client.Contacts.ById(int32(id))
+		if contact != nil {
+			ui.SetCurrentContact(contact)
+		} else {
+			fmt.Printf("no contact %d\n", id)
+		}
+		return nil
+	}
+
+	switch words[0] {
+	case "clear":
+		readline.ClearScreen(readline.Stdout)
+
+	case "quit":
+		return errors.New("Quitting")
+
+	case "status":
+		fmt.Printf("server: %v\n", ui.Client.ServerStatus)
+		fmt.Printf("identity: %v\n", ui.Client.Identity)
+
+	case "connect":
+		status, err := ui.Client.Backend.StartNetwork(context.Background(), &ricochet.StartNetworkRequest{})
+		if err != nil {
+			fmt.Printf("start network error: %v\n", err)
+		} else {
+			fmt.Printf("network started: %v\n", status)
+		}
+
+	case "disconnect":
+		status, err := ui.Client.Backend.StopNetwork(context.Background(), &ricochet.StopNetworkRequest{})
+		if err != nil {
+			fmt.Printf("stop network error: %v\n", err)
+		} else {
+			fmt.Printf("network stopped: %v\n", status)
+		}
+
+	case "contacts":
+		ui.ListContacts()
+
+	case "help":
+		fallthrough
+
+	default:
+		fmt.Println("Commands: clear, quit, status, connect, disconnect, contacts, help")
+	}
+
+	return nil
+}
+
+func (ui *UI) PrintMessage(contact *Contact, outbound bool, text string) {
+	if contact == ui.CurrentContact {
+		if outbound {
+			fmt.Fprintf(ui.Input.Stdout(), "\r%s > %s\n", contact.Data.Nickname, text)
+		} else {
+			fmt.Fprintf(ui.Input.Stdout(), "\r%s < %s\n", contact.Data.Nickname, text)
+		}
+	} else if !outbound {
+		fmt.Fprintf(ui.Input.Stdout(), "\r---- %s < %s\n", contact.Data.Nickname, text)
+	}
+}
+
+func (ui *UI) SendMessage(text string) {
+	_, err := ui.Client.Backend.SendMessage(context.Background(), &ricochet.Message{
+		Sender: &ricochet.Entity{IsSelf: true},
+		Recipient: &ricochet.Entity{
+			ContactId: ui.CurrentContact.Data.Id,
+			Address:   ui.CurrentContact.Data.Address,
+		},
+		Text: text,
+	})
+	if err != nil {
+		fmt.Printf("send message error: %v\n", err)
+	}
+}
+
+func (ui *UI) ListContacts() {
+	byStatus := make(map[ricochet.Contact_Status][]*Contact)
+	for _, contact := range ui.Client.Contacts.Contacts {
+		byStatus[contact.Data.Status] = append(byStatus[contact.Data.Status], contact)
+	}
+
+	order := []ricochet.Contact_Status{ricochet.Contact_ONLINE, ricochet.Contact_UNKNOWN, ricochet.Contact_OFFLINE, ricochet.Contact_REQUEST, ricochet.Contact_REJECTED}
+	for _, status := range order {
+		contacts := byStatus[status]
+		if len(contacts) == 0 {
+			continue
+		}
+		fmt.Printf(". %s\n", strings.ToLower(status.String()))
+		for _, contact := range contacts {
+			fmt.Printf("... [%d] %s\n", contact.Data.Id, contact.Data.Nickname)
+		}
+	}
+}
+
+func (ui *UI) SetCurrentContact(contact *Contact) {
+	if ui.CurrentContact == contact {
+		return
+	}
+
+	ui.CurrentContact = contact
+	if ui.CurrentContact != nil {
+		config := *ui.Input.Config
+		config.Prompt = fmt.Sprintf("%s > ", contact.Data.Nickname)
+		config.UniqueEditLine = true
+		ui.Input.SetConfig(&config)
+		fmt.Printf("--- %s (%s) ---\n", contact.Data.Nickname, strings.ToLower(contact.Data.Status.String()))
+	} else {
+		config := *ui.Input.Config
+		config.Prompt = "> "
+		config.UniqueEditLine = false
+		ui.Input.SetConfig(&config)
+	}
+}