From ce6f2877cef94d5c91bafe2ce4acba52ee22c1fe Mon Sep 17 00:00:00 2001
From: Pierangelo Di Pilato <pierdipi@redhat.com>
Date: Thu, 10 Mar 2022 19:24:48 +0100
Subject: [PATCH] Initialize prefix remapping map to avoid panic (#2453)

A `nil` `target` passed to `AsOptionalMap` causes a panic.

Signed-off-by: Pierangelo Di Pilato <pierdipi@redhat.com>
---
 leaderelection/config.go      |  9 ++--
 leaderelection/config_test.go | 78 +++++++++++++++++++++++++++++------
 2 files changed, 71 insertions(+), 16 deletions(-)

diff --git a/leaderelection/config.go b/leaderelection/config.go
index 3ef47483df..13e0832e5e 100644
--- a/leaderelection/config.go
+++ b/leaderelection/config.go
@@ -101,10 +101,11 @@ func (c *Config) GetComponentConfig(name string) ComponentConfig {
 
 func defaultConfig() *Config {
 	return &Config{
-		Buckets:       1,
-		LeaseDuration: 60 * time.Second,
-		RenewDeadline: 40 * time.Second,
-		RetryPeriod:   10 * time.Second,
+		Buckets:                 1,
+		LeaseDuration:           60 * time.Second,
+		RenewDeadline:           40 * time.Second,
+		RetryPeriod:             10 * time.Second,
+		LeaseNamesPrefixMapping: make(map[string]string),
 	}
 }
 
diff --git a/leaderelection/config_test.go b/leaderelection/config_test.go
index 3b95b448c0..6e821831ef 100644
--- a/leaderelection/config_test.go
+++ b/leaderelection/config_test.go
@@ -38,10 +38,11 @@ const (
 
 func okConfig() *Config {
 	return &Config{
-		Buckets:       1,
-		LeaseDuration: 15 * time.Second,
-		RenewDeadline: 10 * time.Second,
-		RetryPeriod:   2 * time.Second,
+		Buckets:                 1,
+		LeaseDuration:           15 * time.Second,
+		RenewDeadline:           10 * time.Second,
+		RetryPeriod:             2 * time.Second,
+		LeaseNamesPrefixMapping: map[string]string{},
 	}
 }
 
@@ -122,10 +123,11 @@ func TestNewConfigMapFromData(t *testing.T) {
 			"buckets":       "5",
 		},
 		expected: &Config{
-			Buckets:       5,
-			LeaseDuration: 2 * time.Second,
-			RenewDeadline: 3 * time.Second,
-			RetryPeriod:   4 * time.Second,
+			Buckets:                 5,
+			LeaseDuration:           2 * time.Second,
+			RenewDeadline:           3 * time.Second,
+			RetryPeriod:             4 * time.Second,
+			LeaseNamesPrefixMapping: map[string]string{},
 		},
 	}, {
 		name: "prioritize new keys",
@@ -139,10 +141,11 @@ func TestNewConfigMapFromData(t *testing.T) {
 			"buckets":        "7",
 		},
 		expected: &Config{
-			Buckets:       7,
-			LeaseDuration: 1 * time.Second,
-			RenewDeadline: 2 * time.Second,
-			RetryPeriod:   3 * time.Second,
+			Buckets:                 7,
+			LeaseDuration:           1 * time.Second,
+			RenewDeadline:           2 * time.Second,
+			RetryPeriod:             3 * time.Second,
+			LeaseNamesPrefixMapping: map[string]string{},
 		},
 	}}
 
@@ -168,6 +171,57 @@ func TestNewConfigMapFromData(t *testing.T) {
 	}
 }
 
+func TestNewConfigFromMap(t *testing.T) {
+
+	tt := []struct {
+		name    string
+		data    map[string]string
+		want    Config
+		wantErr bool
+	}{{
+		name: "ok config",
+		data: map[string]string{
+			"lease-duration": "15s",
+			"buckets":        "5",
+		},
+		want: Config{
+			Buckets:                 5,
+			LeaseDuration:           15 * time.Second,
+			RenewDeadline:           40 * time.Second,
+			RetryPeriod:             10 * time.Second,
+			LeaseNamesPrefixMapping: map[string]string{},
+		},
+	}, {
+		name: "ok config, prefix map",
+		data: map[string]string{
+			"lease-duration":              "15s",
+			"buckets":                     "5",
+			"map-lease-prefix.reconciler": "reconciler1",
+		},
+		want: Config{
+			Buckets:       5,
+			LeaseDuration: 15 * time.Second,
+			RenewDeadline: 40 * time.Second,
+			RetryPeriod:   10 * time.Second,
+			LeaseNamesPrefixMapping: map[string]string{
+				"reconciler": "reconciler1",
+			},
+		},
+	}}
+
+	for _, tc := range tt {
+		t.Run(tc.name, func(t *testing.T) {
+			c, err := NewConfigFromMap(tc.data)
+			if tc.wantErr != (err != nil) {
+				t.Fatalf("want err %v got %v", tc.wantErr, err)
+			}
+			if diff := cmp.Diff(tc.want, *c); diff != "" {
+				t.Fatal("(-want, +got)", diff)
+			}
+		})
+	}
+}
+
 func TestGetComponentConfig(t *testing.T) {
 	const expectedName = "the-component"
 	cases := []struct {