feat: support sse in api files (#5074)

Signed-off-by: Kevin Wan <wanjunfeng@gmail.com>

tools/goctl/api/gogen/genroutes.go

@@ -40,7 +40,7 @@ func RegisterHandlers(server *rest.Server, serverCtx *svc.ServiceContext) {
 `
 	routesAdditionTemplate = `
 	server.AddRoutes(
-		{{.routes}} {{.jwt}}{{.signature}} {{.prefix}} {{.timeout}} {{.maxBytes}}
+		{{.routes}} {{.jwt}}{{.signature}} {{.prefix}} {{.timeout}} {{.maxBytes}} {{.sse}}
 	)
 `
 	timeoutThreshold = time.Millisecond
@@ -63,6 +63,7 @@ type (
 		routes           []route
 		jwtEnabled       bool
 		signatureEnabled bool
+		sseEnabled       bool
 		authName         string
 		timeout          string
 		middlewares      []string
@@ -123,10 +124,17 @@ func genRoutes(dir, rootPkg string, cfg *config.Config, api *spec.ApiSpec) error
 		if len(g.jwtTrans) > 0 {
 			jwt = jwt + fmt.Sprintf("\n rest.WithJwtTransition(serverCtx.Config.%s.PrevSecret,serverCtx.Config.%s.Secret),", g.jwtTrans, g.jwtTrans)
 		}
+
 		var signature, prefix string
 		if g.signatureEnabled {
 			signature = "\n rest.WithSignature(serverCtx.Config.Signature),"
 		}
+
+		var sse string
+		if g.sseEnabled {
+			sse = "\n rest.WithSSE(),"
+		}
+
 		if len(g.prefix) > 0 {
 			prefix = fmt.Sprintf(`
 rest.WithPrefix("%s"),`, g.prefix)
@@ -172,6 +180,7 @@ rest.WithPrefix("%s"),`, g.prefix)
 			"routes":    routes,
 			"jwt":       jwt,
 			"signature": signature,
+			"sse":       sse,
 			"prefix":    prefix,
 			"timeout":   timeout,
 			"maxBytes":  maxBytes,
@@ -281,6 +290,10 @@ func getRoutes(api *spec.ApiSpec) ([]group, error) {
 		if signature == "true" {
 			groupedRoutes.signatureEnabled = true
 		}
+		sse := g.GetAnnotation("sse")
+		if sse == "true" {
+			groupedRoutes.sseEnabled = true
+		}
 		middleware := g.GetAnnotation("middleware")
 		if len(middleware) > 0 {
 			groupedRoutes.middlewares = append(groupedRoutes.middlewares,