fix: extra labels propagation based on k8s label regex matching (#5216)

* extra labels propagation based on k8s label regex matching

* sanitizing extra labels for spaces

* logger added

* label regex link added

* comment fix

Author: prakash100198

pkg/app/AppCrudOperationService.go

@@ -613,11 +613,25 @@ func (impl AppCrudOperationServiceImpl) getExtraAppLabelsToPropagate(appId int,
 		impl.logger.Errorw("error in finding app and project by appId", "appId", appId, "err", err)
 		return nil, err
 	}
-	return map[string]string{
-		bean3.AppNameDevtronLabel:     appName,
-		bean3.EnvNameDevtronLabel:     envName,
-		bean3.ProjectNameDevtronLabel: appMetaInfo.Team.Name,
-	}, nil
+	regexp := regexp.MustCompile(LabelMatchingRegex)
+	extraAppLabels := make(map[string]string)
+
+	extraAppLabels[bean3.AppNameDevtronLabel] = appName
+	extraAppLabels[bean3.EnvNameDevtronLabel] = envName
+	extraAppLabels[bean3.ProjectNameDevtronLabel] = appMetaInfo.Team.Name
+
+	extraAppLabels = sanitizeLabels(extraAppLabels)
+	for labelKey, labelValue := range extraAppLabels {
+		if regexp.MatchString(labelValue) {
+			extraAppLabels[labelKey] = labelValue
+		} else {
+			// in case extra labels are failing k8s official label matching regex  even after sanitization then
+			//delete the label as this can break deployments.
+			impl.logger.Warnw("extra label failed LabelMatchingRegex validation, regex:- ^(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])?$", "labelKey", labelKey, "labelValue", labelValue)
+			delete(extraAppLabels, labelKey)
+		}
+	}
+	return extraAppLabels, nil
 }
 
 func (impl AppCrudOperationServiceImpl) GetAppLabelsForDeployment(appId int, appName, envName string) ([]byte, error) {

pkg/app/helper.go

@@ -16,6 +16,11 @@
 
 package app
 
+import "strings"
+
+// LabelMatchingRegex is the official k8s label matching regex, pls refer https://github.com/kubernetes/apimachinery/blob/bfd2aff97e594f6aad77acbe2cbbe190acc93cbc/pkg/util/validation/validation.go#L167
+const LabelMatchingRegex = "^(([A-Za-z0-9][-A-Za-z0-9_.]*)?[A-Za-z0-9])?$"
+
 // MergeChildMapToParentMap merges child map of generic type map into parent map of generic type
 // and returns merged mapping, if parentMap is nil then nil is returned.
 func MergeChildMapToParentMap[T comparable, R any](parentMap map[T]R, toMergeMap map[T]R) map[T]R {
@@ -29,3 +34,12 @@ func MergeChildMapToParentMap[T comparable, R any](parentMap map[T]R, toMergeMap
 	}
 	return parentMap
 }
+
+func sanitizeLabels(extraAppLabels map[string]string) map[string]string {
+	for lkey, lvalue := range extraAppLabels {
+		if strings.Contains(lvalue, " ") {
+			extraAppLabels[lkey] = strings.ReplaceAll(lvalue, " ", "_")
+		}
+	}
+	return extraAppLabels
+}