Merge pull request #3 from go-zoox/feat/context-support-sse

feat(context): support sse

components/context/see/body.go

@@ -0,0 +1,54 @@
+package sse
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// SSE ...
+type SSE interface {
+	Retry(delat time.Duration)
+	Event(name, data string)
+	Comment(comment string)
+}
+
+// sse ...
+type sse struct {
+	id      int
+	writer  http.ResponseWriter
+	flusher http.Flusher
+}
+
+func New(rw http.ResponseWriter) SSE {
+	rw.WriteHeader(200)
+	rw.Header().Set("Content-Type", "text/event-stream")
+	rw.Header().Set("Cache-Control", "no-cache")
+	rw.Header().Set("Connection", "keep-alive")
+	rw.Header().Set("Access-Control-Allow-Origin", "*")
+
+	return &sse{
+		writer:  rw,
+		flusher: rw.(http.Flusher),
+	}
+}
+
+func (s *sse) Retry(delay time.Duration) {
+	s.writer.Write([]byte(fmt.Sprintf("retry: %d\n", delay/time.Millisecond)))
+	s.flusher.Flush()
+}
+
+func (s *sse) Event(name string, data string) {
+	s.id++
+
+	s.writer.Write([]byte("event: " + name + "\n"))
+	s.writer.Write([]byte(fmt.Sprintf("id: %d\n", s.id)))
+	s.writer.Write([]byte("data: " + data + "\n\n"))
+
+	s.flusher.Flush()
+}
+
+func (s *sse) Comment(comment string) {
+	s.writer.Write([]byte(": " + comment + "\n"))
+	s.flusher.Flush()
+}

context.go

@@ -25,6 +25,7 @@ import (
 	"github.com/go-zoox/zoox/components/context/form"
 	"github.com/go-zoox/zoox/components/context/param"
 	"github.com/go-zoox/zoox/components/context/query"
+	sse "github.com/go-zoox/zoox/components/context/see"
 	"github.com/go-zoox/zoox/components/context/state"
 	"github.com/go-zoox/zoox/components/context/user"
 	"github.com/go-zoox/zoox/utils"
@@ -56,6 +57,7 @@ type Context struct {
 	body  body.Body
 
 	// response
+	sse sse.SSE
 
 	//
 	cookie  cookie.Cookie
@@ -202,6 +204,15 @@ func (ctx *Context) AddHeader(key string, value string) {
 	ctx.Writer.Header().Add(key, value)
 }
 
+// SSE sets the response header for server-sent events.
+func (ctx *Context) SSE() sse.SSE {
+	if ctx.body == nil {
+		ctx.sse = sse.New(ctx.Writer)
+	}
+
+	return ctx.sse
+}
+
 // BasicAuth returns the user/password pair for Basic Authentication.
 func (ctx *Context) BasicAuth() (username string, password string, ok bool) {
 	return ctx.Request.BasicAuth()