1
0
Fork 0
forgejo/routers/events/events.go
zeripath 791353c03b
Add EventSource support (#11235)
If the browser supports EventSource switch to use this instead of
polling notifications.

Signed-off-by: Andrew Thornton art27@cantab.net
2020-05-07 22:49:00 +01:00

112 lines
2.6 KiB
Go

// Copyright 2020 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package events
import (
"net/http"
"time"
"code.gitea.io/gitea/modules/context"
"code.gitea.io/gitea/modules/eventsource"
"code.gitea.io/gitea/modules/graceful"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/routers/user"
)
// Events listens for events
func Events(ctx *context.Context) {
// FIXME: Need to check if resp is actually a http.Flusher! - how though?
// Set the headers related to event streaming.
ctx.Resp.Header().Set("Content-Type", "text/event-stream")
ctx.Resp.Header().Set("Cache-Control", "no-cache")
ctx.Resp.Header().Set("Connection", "keep-alive")
ctx.Resp.Header().Set("X-Accel-Buffering", "no")
ctx.Resp.WriteHeader(http.StatusOK)
// Listen to connection close and un-register messageChan
notify := ctx.Req.Context().Done()
ctx.Resp.Flush()
shutdownCtx := graceful.GetManager().ShutdownContext()
uid := ctx.User.ID
messageChan := eventsource.GetManager().Register(uid)
unregister := func() {
eventsource.GetManager().Unregister(uid, messageChan)
// ensure the messageChan is closed
for {
_, ok := <-messageChan
if !ok {
break
}
}
}
if _, err := ctx.Resp.Write([]byte("\n")); err != nil {
log.Error("Unable to write to EventStream: %v", err)
unregister()
return
}
timer := time.NewTicker(30 * time.Second)
loop:
for {
select {
case <-timer.C:
event := &eventsource.Event{
Name: "ping",
}
_, err := event.WriteTo(ctx.Resp)
if err != nil {
log.Error("Unable to write to EventStream for user %s: %v", ctx.User.Name, err)
go unregister()
break loop
}
ctx.Resp.Flush()
case <-notify:
go unregister()
break loop
case <-shutdownCtx.Done():
go unregister()
break loop
case event, ok := <-messageChan:
if !ok {
break loop
}
// Handle logout
if event.Name == "logout" {
if ctx.Session.ID() == event.Data {
_, _ = (&eventsource.Event{
Name: "logout",
Data: "here",
}).WriteTo(ctx.Resp)
ctx.Resp.Flush()
go unregister()
user.HandleSignOut(ctx)
break loop
}
// Replace the event - we don't want to expose the session ID to the user
event = (&eventsource.Event{
Name: "logout",
Data: "elsewhere",
})
}
_, err := event.WriteTo(ctx.Resp)
if err != nil {
log.Error("Unable to write to EventStream for user %s: %v", ctx.User.Name, err)
go unregister()
break loop
}
ctx.Resp.Flush()
}
}
timer.Stop()
}