SSE

import "github.com/cloudwego/hertz/pkg/protocol/sse"

func HandleSSE(ctx context.Context, c *app.RequestContext) {
    println("Server Got LastEventID", sse.GetLastEventID(&c.Request))
    w := sse.NewWriter(c)
    for i := 0; i < 5; i++ {
        w.WriteEvent("id-x", "message", []byte("hello\n\nworld"))
        time.Sleep(10 * time.Millisecond)
    }
    w.Close() // Send the last chunk of data to ensure graceful exit. Optional, Hertz will automatically call it after the Handler returns.

    // Please ensure the writer's lifecycle is consistent with the handler. Don't use it asynchronously in the background.
}

import "github.com/cloudwego/hertz/pkg/protocol/sse"

sse.AddAcceptMIME(req) // Some SSE Servers may require explicitly adding Accept: text/event-stream
sse.SetLastEventID(req, "id-123") // For stateful services, you need to tell the Server through SetLastEventID

import "github.com/cloudwego/hertz/pkg/protocol/sse"

func HandleSSE(ctx context.Context, resp *protocol.Response) error {
    r, err := sse.NewReader(resp)
    if err != nil {
    return err
    }

    // You can also manually call the r.Read method
    err = r.ForEach(ctx, func(e *Event) error {
        println("Event:", e.String())
        return nil
    })
    if err != nil { // If the Server disconnects normally, err == nil, no error will be reported
        // Other IO errors or ctx cancelled
        return err
    }
    println("Client LastEventID", r.LastEventID()) // Can be used to save the last received Event ID
    return nil
}

// Event represents a Server-Sent Event (SSE).
type Event struct {
    ID   string // This is the Event ID, sse.Reader will automatically record the last Event ID, which can be obtained using LastEventID()
    Type string // This is the Event Type, common ones like "message"
    Data []byte // For convenience with Unmarshal/Marshal, []byte is used here, but according to the spec, this field must be a utf8 string
    
    // Not recommended to use, mainly for controlling the retry strategy of the browser's SourceEvent.
    // If using Hertz as a Client, you can refer to: https://www.cloudwego.io/docs/hertz/tutorials/basic-feature/retry/
    Retry time.Duration
}