[INTERNAL] Create uniq leader ID per operator deployment (adobe#76)

main.go

@@ -32,6 +32,7 @@ package main
 import (
 	"context"
 	"flag"
+	"fmt"
 	"os"
 	"strings"
 
@@ -128,10 +129,15 @@ func main() {
 		}
 	}
 
+	// hash the watched namespaces to allow for more than one operator deployment per namespace
+	// same watched namespaces will return the same hash so only one operator will be active
+	leaderElectionID := fmt.Sprintf("%s-%x", "controller-leader-election-helper", util.GetMD5Hash(namespaces))
+	setupLog.Info("Using leader electrion id", "LeaderElectionID", leaderElectionID, "watched namespaces", namespaceList)
+
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{
 		Scheme:           scheme,
 		LeaderElection:   enableLeaderElection,
-		LeaderElectionID: "controller-leader-election-helper",
+		LeaderElectionID: leaderElectionID,
 		WebhookServer: webhook.NewServer(webhook.Options{
 			Port:    webhookServerPort,
 			CertDir: webhookCertDir,

pkg/util/util.go

@@ -18,9 +18,11 @@ import (
 	"bytes"
 	"compress/gzip"
 	"context"
+	"crypto/md5"
 	"crypto/tls"
 	"crypto/x509"
 	"encoding/base64"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -551,3 +553,9 @@ func RetryOnConflict(backoff wait.Backoff, fn func() error) error {
 func GetExternalPortForBroker(externalStartingPort, brokerId int32) int32 {
 	return externalStartingPort + brokerId
 }
+
+// Generage MD5 hash for a given string
+func GetMD5Hash(text string) string {
+	hash := md5.Sum([]byte(text))
+	return hex.EncodeToString(hash[:])
+}

pkg/util/util_test.go

@@ -690,3 +690,29 @@ cruise.control.metrics.reporter.kubernetes.mode=true`,
 		}
 	}
 }
+
+func TestGetMD5Hash(t *testing.T) {
+	testCases := []struct {
+		testName string
+		input    string
+		expected string
+	}{
+		{
+			testName: "empty string",
+			input:    "",
+			expected: "d41d8cd98f00b204e9800998ecf8427e",
+		},
+		{
+			testName: "non-empty string",
+			input:    "test",
+			expected: "098f6bcd4621d373cade4e832627b4f6",
+		},
+	}
+
+	for _, test := range testCases {
+		hash := GetMD5Hash(test.input)
+		if hash != test.expected {
+			t.Errorf("Expected: %s  Got: %s", test.expected, hash)
+		}
+	}
+}