func multiCastInstanceCacheChange(w http.ResponseWriter, r *http.Request, mkk string) {
c := appengine.NewContext(r)
ii := instance_mgt.Get(w, r, map[string]interface{}{})
/*
making a get request to all instances
submitting the key and the sender instance id
*/
for i := 0; i < ii.NumInstances; i++ {
// http://[inst0-2].[v2].default.libertarian-islands.appspot.com/instance-info
// note that Hostname already has VersionMajor and Module name as prefixed subdomains
url := fmt.Sprintf("https://%v.%v/_ah/invalidate-instance-cache?mkk=%v&senderInstanceId=%v",
i,
ii.Hostname,
mkk, ii.InstanceID)
_ = url
c.Infof(" url\n%v", url)
//response, err := http.Get(url) // not available in gae
// instead:
client := urlfetch.Client(c)
response, err := client.Get(url)
// with task queues - things would look similar:
// t := taskqueue.NewPOSTTask("/_ah/namespaced-counters/queue-pop", m)
// but we could not enforce each instance getting
// one and exactly one message
// xmpp chat messages have the same disadvantage
// the handler is the same for all instances
// /_ah/xmpp/message/chat/
if err != nil {
c.Infof(" could not launch get request; %v", err)
} else {
defer response.Body.Close()
contents, err := ioutil.ReadAll(response.Body)
if err != nil {
c.Infof(" could not read response; %v", err)
}
c.Infof("%s\n", string(contents))
}
}
}
func invalidate(w http.ResponseWriter, r *http.Request) {
c := appengine.NewContext(r)
ii := instance_mgt.Get(w, r, map[string]interface{}{})
mkk := r.FormValue("mkk")
sii := r.FormValue("senderInstanceId")
c.Infof(" %s --------- %s\n", sii, mkk)
w.WriteHeader(http.StatusOK)
if ii.InstanceID == sii {
w.Write([]byte("Its ME " + mkk + "\n"))
w.Write([]byte(sii))
} else {
w.Write([]byte("got it " + mkk + "\n"))
w.Write([]byte(sii + "\n"))
w.Write([]byte(ii.InstanceID))
}
}