feat: added rule url to the title link in slack message (#1421)

* feat: added rule url to the title link in slack message

* fix: corrected duplication of code for generator url in rules engine

* fix: removed unnecessary import in rules engine

pkg/query-service/rules/alerting.go

@@ -2,12 +2,18 @@ package rules
 
 import (
 	"encoding/json"
+	"fmt"
 	"github.com/pkg/errors"
 	"go.signoz.io/query-service/model"
 	"go.signoz.io/query-service/utils/labels"
+	"net/url"
+	"strings"
 	"time"
 )
 
+// this file contains common structs and methods used by
+// rule engine
+
 // how long before re-sending the alert
 const resolvedRetention = 15 * time.Minute
 
@@ -198,3 +204,30 @@ func (d *Duration) UnmarshalJSON(b []byte) error {
 		return errors.New("invalid duration")
 	}
 }
+
+// prepareRuleGeneratorURL creates an appropriate url
+// for the rule. the URL is sent in slack messages as well as
+// to other systems and allows backtracking to the rule definition
+// from the third party systems.
+func prepareRuleGeneratorURL(ruleId string, source string) string {
+	if source == "" {
+		return source
+	}
+
+	// check if source is a valid url
+	_, err := url.Parse(source)
+	if err != nil {
+		return ""
+	}
+	// since we capture window.location when a new rule is created
+	// we end up with rulesource host:port/alerts/new. in this case
+	// we want to replace new with rule id parameter
+
+	hasNew := strings.LastIndex(source, "new")
+	if hasNew > -1 {
+		ruleURL := fmt.Sprintf("%sedit?ruleId=%s", source[0:hasNew], ruleId)
+		return ruleURL
+	}
+
+	return source
+}

pkg/query-service/rules/promRule.go

@@ -96,7 +96,7 @@ func (r *PromRule) Type() RuleType {
 }
 
 func (r *PromRule) GeneratorURL() string {
-	return r.source
+	return prepareRuleGeneratorURL(r.ID(), r.source)
 }
 
 func (r *PromRule) SetLastError(err error) {

pkg/query-service/rules/templates.go

@@ -17,6 +17,9 @@ import (
 	"go.signoz.io/query-service/utils/times"
 )
 
+// this file contains all the methods and structs
+// related to go templating in rule labels and annotations
+
 type tmplQueryRecord struct {
 	Labels map[string]string
 	Value  float64

pkg/query-service/rules/thresholdRule.go

@@ -63,9 +63,7 @@ func NewThresholdRule(
 		return nil, fmt.Errorf("invalid rule condition")
 	}
 
-	zap.S().Info("msg:", "creating new alerting rule", "\t name:", name, "\t condition:", ruleCondition.String())
-
-	return &ThresholdRule{
+	thresholdRule := &ThresholdRule{
 		id:            id,
 		name:          name,
 		source:        source,
@@ -76,7 +74,11 @@ func NewThresholdRule(
 
 		health: HealthUnknown,
 		active: map[uint64]*Alert{},
-	}, nil
+	}
+
+	zap.S().Info("msg:", "creating new alerting rule", "\t name:", name, "\t condition:", ruleCondition.String(), "\t generatorURL:", thresholdRule.GeneratorURL())
+
+	return thresholdRule, nil
 }
 
 func (r *ThresholdRule) Name() string {
@@ -92,7 +94,7 @@ func (r *ThresholdRule) Condition() *RuleCondition {
 }
 
 func (r *ThresholdRule) GeneratorURL() string {
-	return r.source
+	return prepareRuleGeneratorURL(r.ID(), r.source)
 }
 
 func (r *ThresholdRule) target() *float64 {
@@ -231,9 +233,9 @@ func (r *ThresholdRule) GetEvaluationTimestamp() time.Time {
 // State returns the maximum state of alert instances for this rule.
 // StateFiring > StatePending > StateInactive
 func (r *ThresholdRule) State() AlertState {
+
 	r.mtx.Lock()
 	defer r.mtx.Unlock()
-
 	maxState := StateInactive
 	for _, a := range r.active {
 		if a.State > maxState {