README
¶
go-sse
Server-Sent Events for Go
About
Server-sent events is a method of continuously sending data from a server to the browser, rather than repeatedly requesting it, replacing the "long polling way".
It's supported by all major browsers and for IE/Edge you can use a polyfill.
go-sse is a small library to create a Server-Sent Events server in Go and works with Go 1.9+.
Features
- Multiple channels (isolated)
- Broadcast message to all channels
- Custom headers (useful for CORS)
Last-Event-IDsupport (resend lost messages)- Follow SSE specification
- Compatible with multiple Go frameworks
Instalation
go get github.com/alexandrevicenzi/go-sse
Example
Server side:
package main
import (
"log"
"net/http"
"strconv"
"time"
"github.com/alexandrevicenzi/go-sse"
)
func main() {
// Create SSE server
s := sse.NewServer(nil)
defer s.Shutdown()
// Configure the route
http.Handle("/events/", s)
// Send messages every 5 seconds
go func() {
for {
s.SendMessage("/events/my-channel", sse.SimpleMessage(time.Now().Format("2006/02/01/ 15:04:05")))
time.Sleep(5 * time.Second)
}
}()
log.Println("Listening at :3000")
http.ListenAndServe(":3000", nil)
}
Client side (JavaScript):
e = new EventSource('/events/my-channel');
e.onmessage = function(event) {
console.log(event.data);
};
More examples available here.
License
MIT
Documentation
¶
Overview ¶
Package sse implements Server-Sent Events that supports multiple channels.
Server-sent events is a method of continuously sending data from a server to the browser, rather than repeatedly requesting it.
Examples ¶
Basic usage of sse package.
s := sse.NewServer(nil)
defer s.Shutdown()
http.Handle("/events/", s)
Index ¶
- type Channel
- type Client
- type Message
- type Options
- type Server
- func (s *Server) Channels() []string
- func (s *Server) ClientCount() int
- func (s *Server) CloseChannel(name string)
- func (s *Server) GetChannel(name string) (*Channel, bool)
- func (s *Server) HasChannel(name string) bool
- func (s *Server) Restart()
- func (s *Server) SendMessage(channelName string, message *Message)
- func (s *Server) ServeHTTP(response http.ResponseWriter, request *http.Request)
- func (s *Server) Shutdown()
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Channel ¶
type Channel struct {
// contains filtered or unexported fields
}
Channel represents a server sent events channel.
func (*Channel) ClientCount ¶
ClientCount returns the number of clients connected to this channel.
func (*Channel) Close ¶
func (c *Channel) Close()
Close closes the channel and disconnect all clients.
func (*Channel) LastEventID ¶ added in v1.1.0
LastEventID returns the ID of the last message sent.
func (*Channel) SendMessage ¶
SendMessage broadcast a message to all clients in a channel.
func (*Channel) SendMessageToClient ¶ added in v1.6.0
SendMessage broadcast a message to one client
type Client ¶
type Client struct {
// contains filtered or unexported fields
}
Client represents a web browser connection.
func (*Client) LastEventID ¶ added in v1.1.0
LastEventID returns the ID of the last message sent.
func (*Client) SendMessage ¶
SendMessage sends a message to client.
type Message ¶
type Message struct {
// contains filtered or unexported fields
}
Message represents a event source message.
func NewMessage ¶
NewMessage creates an event source message.
func SimpleMessage ¶
SimpleMessage creates a simple event source message.
type Options ¶
type Options struct {
// RetryInterval change EventSource default retry interval (milliseconds).
RetryInterval int
// Headers allow to set custom headers (useful for CORS support).
Headers map[string]string
// ChannelNameFunc allow to create custom channel names.
// Default channel name is the request path.
ChannelNameFunc func(*http.Request) string
// All usage logs end up in Logger
Logger *log.Logger
// After add clinet function
AfterAddClientFunc func(s *Server, channelName string, client *Client)
}
Options holds server configurations.
type Server ¶
type Server struct {
// contains filtered or unexported fields
}
Server represents a server sent events server.
func (*Server) ClientCount ¶
ClientCount returns the number of clients connected to this server.
func (*Server) CloseChannel ¶
CloseChannel closes a channel.
func (*Server) GetChannel ¶
GetChannel returns the channel associated with name or nil if not found.
func (*Server) HasChannel ¶
HasChannel returns true if the channel associated with name exists.
func (*Server) Restart ¶
func (s *Server) Restart()
Restart closes all channels and clients and allow new connections.
func (*Server) SendMessage ¶
SendMessage broadcast a message to all clients in a channel. If channelName is an empty string, it will broadcast the message to all channels.
Source Files
Directories