vnfs/DAaaS/microservices/GoApps/src/go-hdfs-writer/cmd/hdfs-writer/main.go

   1 package main
   2
   3 import (
   4         "context"
   5         "fmt"
   6         "net/http"
   7         "os"
   8         "os/signal"
   9
  10         handler "hdfs-writer/pkg/handler"
  11         pipeline "hdfs-writer/pkg/pipeline"
  12         utils "hdfs-writer/pkg/utils"
  13 )
  14
  15 func main() {
  16
  17         slogger := utils.GetLoggerInstance()
  18
  19         // Create the server
  20         httpServer := &http.Server{
  21                 Handler: handler.CreateRouter(),
  22                 Addr:    ":9393",
  23         }
  24
  25         connectionsClose := make(chan bool)
  26         go func() {
  27                 c := make(chan os.Signal, 1)
  28                 signal.Notify(c, os.Interrupt)
  29                 <-c // function literal waiting to receive Interrupt signal
  30                 fmt.Printf(":::Got the kill signal:::")
  31                 slogger.Info(":::Got the kill signal:::")
  32                 for eachWriter, eachChannel := range pipeline.ChannelMap {
  33                         slogger.Info("Begin:: Closing writer goroutines::")
  34                         slogger.Infof("Closing writer goroutine :: %s", eachWriter)
  35                         delete(pipeline.ChannelMap, eachWriter)
  36                         eachChannel <- true
  37                 }
  38
  39                 httpServer.Shutdown(context.Background())
  40                 /*once all goroutines are signalled and httpServer is shutdown,
  41                 send close to main thread */
  42                 connectionsClose <- true
  43                 close(connectionsClose)
  44         }()
  45
  46         // Sever starts listening
  47         err := httpServer.ListenAndServe()
  48         if err != nil && err != http.ErrServerClosed {
  49                 slogger.Fatal(err)
  50         }
  51         pipeline.Wg.Wait()
  52         <-connectionsClose //main thread waiting to receive close signal
  53 }