func heartbeat(interval int) chan bool {
retchan := make(chan bool)
go func() {
for {
dbconn, err := database.GetDatabaseConnection()
if err != nil {
logger.Panicln(err)
}
db := &database.DBConn{DBer: dbconn, Appid: AppID}
if err := db.HeartBeat(); err != nil {
logger.Panicln(err)
}
dbconn.Close()
logger.Printf("Watchdog beating every %d minute\n", interval)
retchan <- true
time.Sleep(time.Duration(interval) * time.Minute)
}
}()
return retchan
}
func main() {
dbcon, err := database.GetDatabaseConnection()
if err != nil {
logger.Panicln(err)
}
defer dbcon.Close()
analyser := NewAnalyser(dbcon, redis.NewPool(func() (redis.Conn, error) { return database.GetRedisConnection(getredisconnect()) }, 10))
restful.DefaultResponseMimeType = restful.MIME_JSON
restful.DefaultContainer.EnableContentEncoding(true)
restful.Add(NewAnalyseOGDATRESTService(analyser))
config := swagger.Config{
WebServicesUrl: discoveryhost(),
ApiPath: "/swaggerdoc",
SwaggerPath: "/doc/",
SwaggerFilePath: "swagger-ui/dist/",
WebServices: restful.RegisteredWebServices()}
swagger.InstallSwaggerService(config)
logger.Printf("analyser (%s) listening on port %s\n", AppID, portbinding())
go func() {
logger.Fatal(http.ListenAndServe(":"+portbinding(), nil))
}()
var datachange, urlchange chan []byte
var heartbeatchannel chan bool
populatedatasetinfo := func() {
if err := analyser.populatedatasetinfo(); err != nil {
logger.Panicln(err)
}
}
if !isonlyweb() {
heartbeatchannel = heartbeat(getheartbeatinterval())
<-heartbeatchannel // Wait for the first heartbeat, so the logging in the database is properly set up
populatedatasetinfo()
datachange = analyser.listenredischannel(watcherappid + ":DataChange")
urlchange = analyser.listenredischannel(watcherappid + ":UrlChange")
}
for {
select {
case <-urlchange:
// = REMARK =
// Naive approach here. If a URLChange or DataChange event is triggered,
// the whole analytic database will be recreated. It would be better to trace
// only the affected datasets and only create the relevant statistic.
// In future, urlchange/datachange might contain a JSON-encoded []byte which contains
// the affected IDs
logger.Println("Received URL change notice, re-generating database analysis")
populatedatasetinfo()
case <-datachange:
logger.Println("Received Data change notice, re-generating database analysis")
populatedatasetinfo()
case <-heartbeatchannel:
logger.Println("Idle")
}
}
}
func mymain() int {
if flag.NFlag() == 0 {
fmt.Println("No command line flags given. Usage:")
flag.PrintDefaults()
logger.Panicln("Fatal: No command line flags given")
}
dbconnection, err := database.GetDatabaseConnection()
if err != nil {
logger.Panicln(err)
}
watcherdatabase = &watcherdb{DBConn: database.DBConn{DBer: dbconnection, Appid: AppID}}
defer dbconnection.Close()
if *resettdb {
resetdb()
logger.Println("Info: Earyl exit due to maintainance switches")
return 1
}
if *servetdb {
portal = ckan.NewDataPortalAPIEndpoint(getckanurl(), "2/")
heartbeatinterval := getheartbeatinterval()
heartbeatchannel := heartbeat(heartbeatinterval)
loc, err := time.LoadLocation(gettimezone())
if err != nil {
logger.Panicln(err)
}
logger.Printf("Processing relative to timezone %s\n", loc)
whenurlcheck := urlchecktime(loc)
whendatacheck := datachecktime(loc)
datacheckchan := time.After(0) // assign a ticker of 0 to immediately trigger a data check
urlcheckchan := time.After(whenurlcheck.Sub(time.Now().In(loc)))
for {
select {
case <-urlcheckchan:
anz, err := checkurls(dbconnection)
if err != nil {
logger.Panicln(err)
}
if anz > 0 {
if err := redispublishint("UrlChange", anz); err != nil {
logger.Printf("Cannot publish url change to redis: %s\n", err)
}
}
whenurlcheck = urlchecktime(loc)
urlcheckchan = time.After(whenurlcheck.Sub(time.Now().In(loc)))
case <-datacheckchan:
anz, err := checkdata(dbconnection)
if err != nil {
logger.Panicln(err)
}
if anz > 0 {
if err := redispublishint("DataChange", anz); err != nil {
logger.Printf("Cannot publish data change to redis: %s\n", err)
}
}
whendatacheck = datachecktime(loc)
datacheckchan = time.After(whendatacheck.Sub(time.Now().In(loc)))
case <-time.After(time.Duration(heartbeatinterval) * time.Minute):
}
now := time.Now().In(loc)
logger.Printf("%v: Nothing to do\n", now)
datacheckdiff := whendatacheck.Sub(now)
urlcheckdiff := whenurlcheck.Sub(now)
logger.Printf("Next Data check in %v\n", datacheckdiff)
logger.Printf("Next Url check in %v\n", urlcheckdiff)
// drain the heartbeat channel; without draining, the heartbeat won't get written to the database
select {
case <-heartbeatchannel:
}
if sdidle != nil && *sdidle > 0 {
if datacheckdiff > *sdidle && urlcheckdiff > *sdidle {
logger.Printf("Next activity is more than %v ahead, terminating\n", *sdidle)
return 0
}
}
}
}
return 0
}