Caesar M. Tsai
3f42f2ed01
In scenarios where byte array JSON messages are forwarded (e.g., from MQ), the previous approach required unmarshalling into an object before encoding for SSE.
The updated logic allows []byte to be passed directly, simplifying message forwarding and reducing unnecessary conversions.
// before
byteData := messageFromMQ()
data := make(map[string]any)
json.Unmarshal(byteData, &data)
sse.Encode(new(bytes.Buffer), sse.Event{
Data: data,
})
// after
byteData := messageFromMQ()
sse.Encode(new(bytes.Buffer), sse.Event{
Data: byteData,
})
Server-Sent Events
Server-sent events (SSE) is a technology where a browser receives automatic updates from a server via HTTP connection. The Server-Sent Events EventSource API is standardized as part of HTML5[1] by the W3C.
Sample code
import "github.com/gin-contrib/sse"
func httpHandler(w http.ResponseWriter, req *http.Request) {
// data can be a primitive like a string, an integer or a float
sse.Encode(w, sse.Event{
Event: "message",
Data: "some data\nmore data",
})
// also a complex type, like a map, a struct or a slice
sse.Encode(w, sse.Event{
Id: "124",
Event: "message",
Data: map[string]interface{}{
"user": "manu",
"date": time.Now().Unix(),
"content": "hi!",
},
})
}
event: message
data: some data\\nmore data
id: 124
event: message
data: {"content":"hi!","date":1431540810,"user":"manu"}
Content-Type
fmt.Println(sse.ContentType)
text/event-stream
Decoding support
There is a client-side implementation of SSE coming soon.