implemented network removal if Prometheus is the last container conne…

…cted to a network

swarm.go

@@ -5,6 +5,7 @@ import (
  "encoding/json"
  "io/ioutil"
  "net"
+ "reflect"
  "time"
 
  "strings"
@@ -24,6 +25,7 @@ var prometheusService string
 var discoveryInterval int
 var logLevel string
 var output string
+var clean bool
 var logger = logrus.New()
 
 // allocateIP returns the 3rd last IP in the network range.
@@ -113,6 +115,36 @@ func findPrometheusContainer(serviceName string) (string, error) {
  return promTasks[0].Status.ContainerStatus.ContainerID, nil
 }
 
+func cleanNetworks(prometheusContainerID string) {
+ cli, err := client.NewEnvClient()
+
+ networkFilters := filters.NewArgs()
+ networkFilters.Add("driver", "overlay")
+ networks, err := cli.NetworkList(context.Background(), types.NetworkListOptions{Filters: networkFilters})
+ if err != nil {
+ panic(err)
+ }
+
+ for _, network := range networks {
+ if network.Name == "ingress" {
+ continue
+ }
+
+ if len(network.Containers) == 1 && reflect.ValueOf(network.Containers).MapKeys()[0].String() == prometheusContainerID {
+ logger.Info("Network ", network.Name, " contains only the Prometheus container. Disconnecting and removing network.")
+ cli.NetworkDisconnect(context.Background(), network.ID, prometheusContainerID, true)
+ if err != nil {
+ logger.Error(err)
+ }
+ err := cli.NetworkRemove(context.Background(), network.ID)
+ if err != nil {
+ logger.Error(err)
+ }
+ }
+ }
+
+}
+
 type scrapeService struct {
  ServiceName string
  scrapeTasks scrapeTask
@@ -220,6 +252,9 @@ func discoveryProcess(cmd *cobra.Command, args []string) {
  }
 
  discoverSwarm(prometheusContainerID)
+ if clean {
+ cleanNetworks(prometheusContainerID)
+ }
  }
 }
 
@@ -235,6 +270,7 @@ func main() {
  cmdDiscover.Flags().IntVarP(&discoveryInterval, "interval", "i", 30, "The interval, in seconds, at which the discovery process is kicked off")
  cmdDiscover.Flags().StringVarP(&logLevel, "loglevel", "l", "info", "Specify log level: debug, info, warn, error")
  cmdDiscover.Flags().StringVarP(&output, "output", "o", "swarm-endpoints.json", "Output file that contains the Prometheus endpoints.")
+ cmdDiscover.Flags().BoolVarP(&clean, "clean", "c", true, "Disconnects unused networks from the Prometheus container, and deletes them.")
 
  var rootCmd = &cobra.Command{Use: "promswarm"}
  rootCmd.AddCommand(cmdDiscover)