Add decode hooks to other parse functions

Now that the original config parsing leaves the opaque maps unmodified
these secondary decodes must use the hooks to normalize fields.

agent/structs/connect_proxy_config.go

@@ -426,8 +426,6 @@ type ExposePath struct {
 	ParsedFromCheck bool
 }
 
-// TODO: this is most likely not used. The API type is the one to be deserialized
-// with JSON
 func (t *ExposePath) UnmarshalJSON(data []byte) (err error) {
 	type Alias ExposePath
 	aux := &struct {

agent/xds/config.go

@@ -58,7 +58,22 @@ type ProxyConfig struct {
 // allows caller to choose whether and how to report the error.
 func ParseProxyConfig(m map[string]interface{}) (ProxyConfig, error) {
 	var cfg ProxyConfig
-	err := mapstructure.WeakDecode(m, &cfg)
+	decodeConf := &mapstructure.DecoderConfig{
+		DecodeHook: mapstructure.ComposeDecodeHookFunc(
+			decode.HookNormalizeHCLNestedBlocks,
+			decode.HookTranslateKeys,
+		),
+		Result:           &cfg,
+		WeaklyTypedInput: true,
+	}
+	decoder, err := mapstructure.NewDecoder(decodeConf)
+	if err != nil {
+		return cfg, err
+	}
+	if err := decoder.Decode(m); err != nil {
+		return cfg, err
+	}
+
 	// Set defaults (even if error is returned)
 	if cfg.Protocol == "" {
 		cfg.Protocol = "tcp"
@@ -202,7 +217,11 @@ func (p PassiveHealthCheck) AsOutlierDetection() *envoycluster.OutlierDetection
 func ParseUpstreamConfigNoDefaults(m map[string]interface{}) (UpstreamConfig, error) {
 	var cfg UpstreamConfig
 	config := &mapstructure.DecoderConfig{
-		DecodeHook:       mapstructure.StringToTimeDurationHookFunc(),
+		DecodeHook: mapstructure.ComposeDecodeHookFunc(
+			decode.HookNormalizeHCLNestedBlocks,
+			decode.HookTranslateKeys,
+			mapstructure.StringToTimeDurationHookFunc(),
+		),
 		Result:           &cfg,
 		WeaklyTypedInput: true,
 	}