Merge pull request #3 from whiskeyjimbo/combine-certrules-and-rules

refactor: combine certrules and rules together and add a type

Author: whiskeyjimbo

examples/config.yaml

@@ -76,25 +76,41 @@ sites:
 
 rules:
   - name: "api_high_latency"
-    condition: "responseTime > 500"  # milliseconds
+    type: "standard"
+    condition: "responseTime > 500"
     tags: ["http-api", "https-api"]
     notifications: ["log"]
 
   - name: "api_critical_downtime"
-    condition: "downtime > 30s"  # seconds
+    type: "standard"
+    condition: "downtime > 30s"
     tags: ["service-api", "critical"]
     notifications: ["log"]
 
   - name: "db_downtime_warning"
-    condition: "downtime > 10s"  # seconds
+    type: "standard"
+    condition: "downtime > 10s"
     tags: ["service-db"]
     notifications: ["log"]
 
   - name: "prod_service_degraded"
-    condition: "responseTime > 1000 || downtime > 0" 
+    type: "standard"
+    condition: "responseTime > 1000 || downtime > 0"
     tags: ["prod", "critical"]
     notifications: ["log"]
 
+  - name: "cert_expiring_soon"
+    type: "cert"
+    minDaysValidity: 30
+    tags: ["https-api"]
+    notifications: ["log"]
+
+  - name: "cert_critical"
+    type: "cert"
+    minDaysValidity: 7
+    tags: ["https-api", "critical"]
+    notifications: ["log"]
+
 notifications:
   - type: "log"    # Currently the only implemented type
   # Future notification types:
@@ -105,14 +121,3 @@ notifications:
   #   smtp_server: "smtp.example.com"
   #   from: "alerts@example.com"
   #   to: ["ops@example.com"]
-
-certRules:
-  - name: "cert_expiring_soon"
-    minDaysValidity: 30
-    tags: ["https-api"]
-    notifications: ["log"]
-
-  - name: "cert_critical"
-    minDaysValidity: 7
-    tags: ["https-api", "critical"]
-    notifications: ["log"]

internal/config/config.go

@@ -22,7 +22,6 @@ type Config struct {
 	Sites         []SiteConfig         `yaml:"sites"`
 	Rules         []rules.Rule         `yaml:"rules"`
 	Notifications []NotificationConfig `yaml:"notifications"`
-	CertRules     []rules.CertRule     `yaml:"certRules"`
 }
 
 type SiteConfig struct {

internal/monitor/helpers.go

@@ -106,7 +106,11 @@ func processRule(
 	ruleModeResolver *config.RuleModeResolver,
 	failingHosts []string,
 ) {
-	ruleResult := rules.EvaluateRule(rule, downtime, stats.AvgResponseTime)
+	params := rules.EvaluationParams{
+		Downtime:     downtime,
+		ResponseTime: stats.AvgResponseTime,
+	}
+	ruleResult := rules.EvaluateRule(rule, params)
 	if !shouldSendNotification(ruleResult) {
 		return
 	}

internal/rules/cert_rules.go

@@ -5,20 +5,14 @@ import (
 	"time"
 )
 
-type CertRule struct {
-	Name            string   `yaml:"name"`
-	MinDaysValidity int      `yaml:"minDaysValidity"`
-	Tags            []string `yaml:"tags"`
-	Notifications   []string `yaml:"notifications"`
-}
-
-func EvaluateCertRule(rule CertRule, certExpiryTime time.Time) RuleResult {
+func evaluateCertRule(rule Rule, certExpiryTime time.Time) RuleResult {
 	daysUntilExpiry := time.Until(certExpiryTime).Hours() / 24
 
 	if daysUntilExpiry < float64(rule.MinDaysValidity) {
 		return RuleResult{
 			Satisfied: true,
-			Message:   fmt.Sprintf("Certificate expires in %.1f days (threshold: %d days)", daysUntilExpiry, rule.MinDaysValidity),
+			Message: fmt.Sprintf("Certificate expires in %.1f days (threshold: %d days)",
+				daysUntilExpiry, rule.MinDaysValidity),
 		}
 	}
 

internal/rules/rules.go

@@ -9,11 +9,20 @@ import (
 	"github.com/expr-lang/expr"
 )
 
+type RuleType string
+
+const (
+	StandardRule RuleType = "standard"
+	CertRule     RuleType = "cert"
+)
+
 type Rule struct {
-	Name          string   `yaml:"name"`
-	Condition     string   `yaml:"condition"`
-	Tags          []string `yaml:"tags"`
-	Notifications []string `yaml:"notifications"`
+	Name            string   `yaml:"name"`
+	Type            RuleType `yaml:"type"`
+	Tags            []string `yaml:"tags"`
+	Notifications   []string `yaml:"notifications"`
+	Condition       string   `yaml:"condition,omitempty"`
+	MinDaysValidity int      `yaml:"minDaysValidity,omitempty"`
 }
 
 type RuleResult struct {
@@ -27,7 +36,39 @@ var (
 	ErrInvalidSyntax  = errors.New("invalid rule syntax")
 )
 
-func EvaluateRule(rule Rule, downtime, responseTime time.Duration) RuleResult {
+type EvaluationParams struct {
+	Downtime       time.Duration
+	ResponseTime   time.Duration
+	CertExpiryTime time.Time
+}
+
+func (r Rule) Validate() error {
+	if r.Type == "" {
+		return fmt.Errorf("rule type must be specified")
+	}
+	switch r.Type {
+	case StandardRule, CertRule:
+		return nil
+	default:
+		return fmt.Errorf("invalid rule type: %s", r.Type)
+	}
+}
+
+func EvaluateRule(rule Rule, params EvaluationParams) RuleResult {
+	if err := rule.Validate(); err != nil {
+		return RuleResult{Error: err}
+	}
+
+	switch rule.Type {
+	case StandardRule:
+		return evaluateStandardRule(rule, params.Downtime, params.ResponseTime)
+	case CertRule:
+		return evaluateCertRule(rule, params.CertExpiryTime)
+	}
+	return RuleResult{Error: fmt.Errorf("unsupported rule type: %s", rule.Type)}
+}
+
+func evaluateStandardRule(rule Rule, downtime, responseTime time.Duration) RuleResult {
 	if rule.Condition == "" {
 		return RuleResult{Error: ErrEmptyCondition}
 	}