cleanup: remove disabling metrics from kuma-cp.defaults

These are not optional for a while. Add a test to check to kuma-cp.defaults.yaml
doesn't not contain extra configs

Fix #4854

Signed-off-by: Charly Molter <charly.molter@konghq.com>

pkg/config/app/kuma-cp/default_config_test.go

@@ -12,20 +12,16 @@ import (
 
 var _ = Describe("Default config", func() {
 
-	var backupEnvVars []string
-
-	BeforeEach(func() {
-		backupEnvVars = os.Environ()
+	It("should be check against the kuma-cp.defaults.yaml file", func() {
+		backupEnvVars := os.Environ()
 		os.Clearenv()
-	})
-	AfterEach(func() {
-		for _, envVar := range backupEnvVars {
-			parts := strings.SplitN(envVar, "=", 2)
-			Expect(os.Setenv(parts[0], parts[1])).To(Succeed())
-		}
-	})
+		defer func() {
+			for _, envVar := range backupEnvVars {
+				parts := strings.SplitN(envVar, "=", 2)
+				Expect(os.Setenv(parts[0], parts[1])).To(Succeed())
+			}
 
-	It("should be check against the kuma-cp.defaults.yaml file", func() {
+		}()
 		// given
 		cfg := Config{}
 
@@ -36,4 +32,10 @@ var _ = Describe("Default config", func() {
 		Expect(err).ToNot(HaveOccurred())
 		Expect(DefaultConfig()).To(Equal(cfg), "The default config generated by Kuma and kuma-cp.defaults.yaml config file are different. Please update the kuma-cp.defaults.yaml file.")
 	})
+
+	It("kuma-cp.defaults.yaml should not have extra keys", func() {
+		cfg := Config{}
+		err := config.LoadWithOption("kuma-cp.defaults.yaml", &cfg, true, false, false)
+		Expect(err).ToNot(HaveOccurred())
+	})
 })

pkg/config/app/kuma-cp/kuma-cp.defaults.yaml

@@ -290,15 +290,11 @@ defaults:
 # Metrics configuration
 metrics:
   dataplane:
-    # Enables collecting metrics from Dataplane
-    enabled: true # ENV: KUMA_METRICS_DATAPLANE_ENABLED
     # How many latest subscriptions will be stored in DataplaneInsight object, if equals 0 then unlimited
     subscriptionLimit: 2 # ENV: KUMA_METRICS_DATAPLANE_SUBSCRIPTION_LIMIT
     # How long data plane proxy can stay Online without active xDS connection
     idleTimeout: 5m # ENV: KUMA_METRICS_DATAPLANE_IDLE_TIMEOUT
   zone:
-    # Enables collecting metrics from Zone
-    enabled: true # ENV: KUMA_METRICS_ZONE_ENABLED
     # How many latest subscriptions will be stored in ZoneInsights object, if equals 0 then unlimited
     subscriptionLimit: 10 # ENV: KUMA_METRICS_ZONE_SUBSCRIPTION_LIMIT
     # How long zone can stay Online without active KDS connection

pkg/config/loader.go

@@ -11,39 +11,41 @@ import (
 )
 
 func Load(file string, cfg Config) error {
+	return LoadWithOption(file, cfg, false, true, true)
+}
+
+func LoadWithOption(file string, cfg Config, strict bool, includeEnv bool, validate bool) error {
 	if file == "" {
 		core.Log.Info("Skipping reading config from file")
-	} else if err := loadFromFile(file, cfg); err != nil {
+	} else if err := loadFromFile(file, cfg, strict); err != nil {
 		return err
 	}
 
-	if err := loadFromEnv(cfg); err != nil {
-		return err
+	if includeEnv {
+		if err := envconfig.Process("", cfg); err != nil {
+			return err
+		}
 	}
-
-	if err := cfg.Validate(); err != nil {
-		return errors.Wrapf(err, "Invalid configuration")
+	if validate {
+		if err := cfg.Validate(); err != nil {
+			return errors.Wrapf(err, "Invalid configuration")
+		}
 	}
 	return nil
 }
 
-func loadFromFile(file string, cfg Config) error {
-	if !fileExists(file) {
+func loadFromFile(file string, cfg Config, strict bool) error {
+	if _, err := os.Stat(file); err != nil {
 		return errors.Errorf("Failed to access configuration file %q", file)
 	}
-	if contents, err := os.ReadFile(file); err != nil {
+	contents, err := os.ReadFile(file)
+	if err != nil {
 		return errors.Wrapf(err, "Failed to read configuration from file %q", file)
-	} else if err := yaml.Unmarshal(contents, cfg); err != nil {
-		return errors.Wrapf(err, "Failed to parse configuration from file %q", file)
 	}
-	return nil
-}
-
-func loadFromEnv(config Config) error {
-	return envconfig.Process("", config)
-}
-
-func fileExists(path string) bool {
-	_, err := os.Stat(path)
-	return err == nil
+	if strict {
+		err = yaml.UnmarshalStrict(contents, cfg)
+	} else {
+		err = yaml.Unmarshal(contents, cfg)
+	}
+	return errors.Wrapf(err, "Failed to parse configuration from file %q", file)
 }