jolta

README

Jolta

This is an event-based networking library for Go, based on KCP and Smux.

Features

• Secure: all of the data is encrypted by default, and there's no way to disable it.
• Small latency: the KCP protocol is designed for small latencies.
• Small: the entire library is ~650 lines of code.

Examples

(Server) Start a server

package main

import "github.com/zeozeozeo/jolta"

func main() {
    // server address, password, salt
    server := jolta.NewServer("127.0.0.1:7145", []byte("test password"), []byte("test salt"))

    // listen (this is blocking)
	if err := server.Listen(); err != nil {
		panic(err)
	}
}

(Client) Connect to a server

package main

import "github.com/zeozeozeo/jolta"

func main() {
    // server address, password and salt
    // of the server you want to connect to
    client := jolta.NewClient("127.0.0.1:7145", []byte("test password"), []byte("test salt"))

    // connect to the server (this is blocking)
    if err := client.Connect(); err != nil {
		panic(err)
	}
}

(Client) Send and recieve messages to/from other clients

func main() {
    // client := jolta.NewClient(...)

    client.OnConnect(func(client *jolta.Client) {
        // send a message to all connected
        // clients, the event name can be
        // any string
		client.SendAll("any event name", []byte("hello from client!"))

        // get all clients connected to
        // the server
        clients, err := client.GetClients()
        if err != nil || len(clients) == 0 {
            return
        }

        // send a message to some client
        // (clients are represented with
        // ID's, 1 being the client that
        // connected first)
        client.SendTo("any event name", clients[0], []byte("hi client!"))
	})

    // recieve messages from other clients
	client.On("any event name", func(client *jolta.Client, senderId uint32, data []byte) {
		// do anything you want...
        fmt.Printf("client %d says: %s\n", senderId, string(data))
	})

    // client.Connect()...
}

See more examples in internal/examples

Documentation

Index

• Variables
• type Client
  • func NewClient(address string, password, salt []byte) *Client
  • func (client *Client) Connect() error
  • func (client *Client) Disconnect()
  • func (client *Client) GetClients() ([]uint32, error)
  • func (client *Client) ID() uint32
  • func (client *Client) On(eventName string, on func(client *Client, senderId uint32, data []byte))
  • func (client *Client) OnConnect(on func(client *Client))
  • func (client *Client) OnDisconnect(on func(client *Client))
  • func (client *Client) SendAll(eventName string, data []byte) error
  • func (client *Client) SendTo(eventName string, id uint32, data []byte) error
• type Connection
  • func (conn *Connection) Disconnect()
  • func (conn *Connection) ID() uint32
  • func (conn *Connection) Send(eventName string, senderId uint32, data []byte) error
• type Event
• type Packet
• type Server
  • func NewServer(address string, password, salt []byte) *Server
  • func (server *Server) Listen() error
  • func (server *Server) OnConnect(on func(conn *Connection))
  • func (server *Server) OnDisconnect(on func(conn *Connection))
  • func (server *Server) OnMessage(on func(conn *Connection, eventName string, senderId uint32, data []byte))
  • func (server *Server) OnStart(on func(server *Server))
  • func (server *Server) Stop()

Variables

var (
	ErrDisconnected error = errors.New("jolta client: disconnected")
)

Types

type Client

type Client struct {
	Address      string
	Password     []byte
	Salt         []byte
	DataShards   int // default: 10.
	ParityShards int // default: 3.
	KeyIter      int // default: 1024.
	KeyLen       int // default: 32.
	Events       []*Event
	Timeout      time.Duration // Timeout for accepting streams. 0 disables the timeout.
	// contains filtered or unexported fields
}

func NewClient

func NewClient(address string, password, salt []byte) *Client

NewClient creates a new client.

func (*Client) Connect

func (client *Client) Connect() error

Connect connects the client to the server.

func (*Client) Disconnect

func (client *Client) Disconnect()

Disconnect disconnects the client from the server.

func (*Client) GetClients

func (client *Client) GetClients() ([]uint32, error)

GetClients returns all client ID's that are connected to the server.

func (*Client) ID

func (client *Client) ID() uint32

Returns the client ID. An ID of 0 means that the client is not connected yet.

func (*Client) On

func (client *Client) On(eventName string, on func(client *Client, senderId uint32, data []byte))

On adds a hander to an event name. Empty event names will be called on any event.

func (*Client) OnConnect

func (client *Client) OnConnect(on func(client *Client))

OnDisconnect sets the function that is called when the client is connected.

func (*Client) OnDisconnect

func (client *Client) OnDisconnect(on func(client *Client))

OnDisconnect sets the function that is called before the client is disconnected.

func (*Client) SendAll

func (client *Client) SendAll(eventName string, data []byte) error

SendAll sends a message to all clients.

func (*Client) SendTo

func (client *Client) SendTo(eventName string, id uint32, data []byte) error

SendTo sends a message to a client with that ID.

type Connection

type Connection struct {
	// contains filtered or unexported fields
}

func (*Connection) Disconnect

func (conn *Connection) Disconnect()

Disconnect disconnects the client from the server.

func (*Connection) ID

func (conn *Connection) ID() uint32

ID returns the client ID.

func (*Connection) Send

func (conn *Connection) Send(eventName string, senderId uint32, data []byte) error

Send sends a message to the client.

type Event

type Event struct {
	Func func(client *Client, senderId uint32, data []byte)
	Name string
}

type Packet

type Packet uint8

const (
	PACKET_GETID      Packet = 0 // This packet is sent by the client when it's connected, the server responds with the client's ID.
	PACKET_SENDTO     Packet = 1 // The client tells the server to send a message to a specified user ID
	PACKET_SENDALL    Packet = 2 // The client tells the server to send a message to all clients
	PACKET_MESSAGE    Packet = 3 // The server tells the client that someone sent it a new message
	PACKET_GETCLIENTS Packet = 4 // The client asks the server to list all clients
)

type Server

type Server struct {
	Address      string
	Password     []byte
	Salt         []byte
	DataShards   int // default: 10
	ParityShards int // default: 3
	Connections  []*Connection
	KeyIter      int           // default: 1024
	KeyLen       int           // default: 32
	Timeout      time.Duration // Timeout for accepting streams. 0 disables the timeout.
	// contains filtered or unexported fields
}

func NewServer

func NewServer(address string, password, salt []byte) *Server

NewServer creates a new server context.

func (*Server) Listen

func (server *Server) Listen() error

Listen starts the server and listens for connections.

func (*Server) OnConnect

func (server *Server) OnConnect(on func(conn *Connection))

OnConnect sets the function that is called when a client is connected.

func (*Server) OnDisconnect

func (server *Server) OnDisconnect(on func(conn *Connection))

OnDisconnect sets the function that is called when a client is connected.

func (*Server) OnMessage

func (server *Server) OnMessage(on func(conn *Connection, eventName string, senderId uint32, data []byte))

OnMessage sets the function that is called when a client receives a message.

func (*Server) OnStart

func (server *Server) OnStart(on func(server *Server))

OnStart sets the function that is called when the server is started.

func (*Server) Stop

func (server *Server) Stop()

Stop disconnects all clients and stops the server.