feat: add ignoreTemplatedValues param to the ignoreTemplatedValues va…

…lidator (#49)

Signed-off-by: Martin Chodur <[email protected]>

CHANGELOG.md

@@ -6,6 +6,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+- Added new param `ignoreTemplatedValues` to the `labelHasAllowedValue` validator to ignore templated values in the label.
 - Added new validation rule scope `Group` to validate the rule group itself (not the rules in it).
 - Added new `Group` scope validator `hasAllowedEvaluationInterval` to check if the rule group has the `interval` in the configured range and possibility to enforce it to be configured.
 - CHANGED: The validator `allowedSourceTenants` is now allowed only in the `Group` scope validation rules.

docs/validations.md

@@ -89,6 +89,9 @@ params:
 
 Fails if rule label value is not one of the allowed values. If the `commaSeparatedValue` is set to true, the label value
 to true, the label value is split by a comma, and the distinct values are checked if valid.
+Since the labels can be templated, but Promruval cannot tell if the resulting value will be valid,
+there is the `ignoreTemplatedValues` option, that allows you to ignore the templated values.
+
 > It's quite common to have well known severities for alerts which can be important even in the
 > Alertmanager routing tree. Ths is how you can make sure only the well-known severities are used.
 
@@ -97,6 +100,7 @@ params:
   label: "foo"
   allowedValues: [ "foo", "bar" ]
   commaSeparatedValue: true
+  ignoreTemplatedValues: false
 ```
 
 ### `nonEmptyLabels`

examples/human_readable.html

@@ -15,7 +15,7 @@ <h2><a href="#check-severity-label">check-severity-label</a></h2>
   <h2><a href="#check-team-label">check-team-label</a></h2>
 	  <ul>
 		<li>Alert has labels: <code>xxx</code></li>
-		<li>Alert label <code>team</code> has one of the allowed values: <code>[email protected]</code></li>
+		<li>Alert label <code>team</code> has one of the allowed values: <code>[email protected]</code> (templated values are ignored)</li>
 	  </ul>
 
   <h2><a href="#check-playbook-annotation">check-playbook-annotation</a></h2>

examples/human_readable.md

@@ -12,7 +12,7 @@ Validation rules:
 
   check-team-label
     - Alert has labels: `xxx`
-    - Alert label `team` has one of the allowed values: `[email protected]`
+    - Alert label `team` has one of the allowed values: `[email protected]` (templated values are ignored)
 
   check-playbook-annotation
     - Alert has any of these annotations: `playbook`,`link`

examples/rules/rules.yaml

@@ -41,6 +41,19 @@ groups:
             # ignore_validations: expressionSelectorsMatchesAnything, hasLabels
           }
         for: 1m
+        labels:
+          team: "{{ .Labels.team }}"
+        annotations:
+          title: test alert
+          playbook: http://foo.bar/nonexisting/playbook
+
+      - alert: test2
+        expr: up == 0
+        for: 1m
+        labels:
+          team: "{{ .Labels.team }}"
+          xxx: fooo
+          severity: critical
         annotations:
           title: test alert
           playbook: http://foo.bar/nonexisting/playbook

examples/validation.yaml

@@ -41,6 +41,7 @@ validationRules:
           label: "team"
           allowedValues:
             - "[email protected]"
+          ignoreTemplatedValues: true
 
   - name: check-playbook-annotation
     scope: Alert

pkg/validator/labels.go

@@ -143,9 +143,10 @@ func (h hasAnyOfLabels) Validate(_ unmarshaler.RuleGroup, rule rulefmt.Rule, _ *
 
 func newLabelHasAllowedValue(paramsConfig yaml.Node) (Validator, error) {
 	params := struct {
-		Label               string   `yaml:"label"`
-		AllowedValues       []string `yaml:"allowedValues"`
-		CommaSeparatedValue bool     `yaml:"commaSeparatedValue"`
+		Label                 string   `yaml:"label"`
+		AllowedValues         []string `yaml:"allowedValues"`
+		CommaSeparatedValue   bool     `yaml:"commaSeparatedValue"`
+		IgnoreTemplatedValues bool     `yaml:"ignoreTemplatedValues"`
 	}{}
 	if err := paramsConfig.Decode(&params); err != nil {
 		return nil, err
@@ -156,28 +157,36 @@ func newLabelHasAllowedValue(paramsConfig yaml.Node) (Validator, error) {
 	if len(params.AllowedValues) == 0 {
 		return nil, fmt.Errorf("missing allowedValues")
 	}
-	return &labelHasAllowedValue{label: params.Label, allowedValues: params.AllowedValues, commaSeparatedValue: params.CommaSeparatedValue}, nil
+	return &labelHasAllowedValue{label: params.Label, allowedValues: params.AllowedValues, commaSeparatedValue: params.CommaSeparatedValue, ignoreTemplatedValues: params.IgnoreTemplatedValues}, nil
 }
 
 type labelHasAllowedValue struct {
-	label               string
-	allowedValues       []string
-	commaSeparatedValue bool
+	label                 string
+	allowedValues         []string
+	commaSeparatedValue   bool
+	ignoreTemplatedValues bool
 }
 
 func (h labelHasAllowedValue) String() string {
 	text := fmt.Sprintf("has one of the allowed values: `%s`", strings.Join(h.allowedValues, "`,`"))
 	if h.commaSeparatedValue {
 		text = "split by comma " + text
 	}
-	return fmt.Sprintf("label `%s` %s", h.label, text)
+	text = fmt.Sprintf("label `%s` %s", h.label, text)
+	if h.ignoreTemplatedValues {
+		text += " (templated values are ignored)"
+	}
+	return text
 }
 
 func (h labelHasAllowedValue) Validate(_ unmarshaler.RuleGroup, rule rulefmt.Rule, _ *prometheus.Client) []error {
 	ruleValue, ok := rule.Labels[h.label]
 	if !ok {
 		return []error{}
 	}
+	if h.ignoreTemplatedValues && strings.Contains(ruleValue, "{{") {
+		return []error{}
+	}
 	valuesToCheck := []string{ruleValue}
 	if h.commaSeparatedValue {
 		valuesToCheck = strings.Split(ruleValue, ",")

pkg/validator/validator_test.go

@@ -65,6 +65,8 @@ var testCases = []struct {
 	{name: "ruleHasCsvLabelWithAllowedValue", validator: labelHasAllowedValue{label: "foo", allowedValues: []string{"bar"}, commaSeparatedValue: true}, rule: rulefmt.Rule{Labels: map[string]string{"foo": "xxx,bar"}}, expectedErrors: 0},
 	{name: "ruleDoesNotHaveLabelWithAllowedValue", validator: labelHasAllowedValue{label: "foo", allowedValues: []string{"bar"}}, rule: rulefmt.Rule{Labels: map[string]string{"foo": "xxx"}}, expectedErrors: 1},
 	{name: "ruleHasCsvLabelWithoutAllowedValue", validator: labelHasAllowedValue{label: "foo", allowedValues: []string{"bar"}, commaSeparatedValue: true}, rule: rulefmt.Rule{Labels: map[string]string{"foo": "xxx,yyy"}}, expectedErrors: 1},
+	{name: "ruleHasTemplatedLabelAndCannotHave", validator: labelHasAllowedValue{label: "foo", allowedValues: []string{"bar"}, ignoreTemplatedValues: false}, rule: rulefmt.Rule{Labels: map[string]string{"foo": "{{ .Labels.foo }}"}}, expectedErrors: 1},
+	{name: "ruleHasTemplatedLabelAndCannotHave", validator: labelHasAllowedValue{label: "foo", allowedValues: []string{"bar"}, ignoreTemplatedValues: true}, rule: rulefmt.Rule{Labels: map[string]string{"foo": "{{ .Labels.foo }}"}}, expectedErrors: 0},
 
 	// annotationHasAllowedValue
 	{name: "ruleHasAnnotationWithAllowedValue", validator: annotationHasAllowedValue{annotation: "foo", allowedValues: []string{"bar"}}, rule: rulefmt.Rule{Annotations: map[string]string{"foo": "bar"}}, expectedErrors: 0},