dnslb-ctl: add block subcommand.

cmd/dnslb-ctl/block.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/Cloud-Foundations/Dominator/lib/log"
+	"github.com/Cloud-Foundations/golib/pkg/loadbalancing/dnslb/config"
+)
+
+func blockSubcommand(args []string, logger log.DebugLogger) error {
+	if err := block(args[0], logger); err != nil {
+		return fmt.Errorf("Error blocking IP: %s: %s", args[0], err)
+	}
+	return nil
+}
+
+func block(ip string, logger log.DebugLogger) error {
+	signalChannel := make(chan os.Signal, 1)
+	signal.Notify(signalChannel, syscall.SIGINT, syscall.SIGTERM)
+	cancelChannel := make(chan struct{}, 1)
+	go func() {
+		<-signalChannel
+		logger.Println("caught signal: cleaning up gracefully")
+		cancelChannel <- struct{}{}
+	}()
+	return config.Block(cfgData, ip, *blockDuration, cancelChannel, logger)
+}

cmd/dnslb-ctl/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"time"
 
 	"github.com/Cloud-Foundations/Dominator/lib/decoders"
 	"github.com/Cloud-Foundations/Dominator/lib/flags/commands"
@@ -16,6 +17,8 @@ import (
 )
 
 var (
+	blockDuration = flag.Duration("blockDuration", time.Minute*15,
+		"Duration to block")
 	configFile = flag.String("configFile", "",
 		"Name of file containing configuration")
 
@@ -38,6 +41,7 @@ func printUsage() {
 var subcommands = []commands.Command{
 	{"rolling-replace", "region...", 1, 3,
 		rollingReplaceSubcommand},
+	{"block", "IP", 1, 1, blockSubcommand},
 }
 
 func doMain() int {