Add support for keep_firing_for in the parser

cmd/pint/tests/0121_rule_for.txt

@@ -10,7 +10,10 @@ rules/0001.yml:6 Bug: this alert rule must have a 'for' field with a minimum dur
 rules/0001.yml:9 Bug: this alert rule must have a 'for' field with a maximum duration of 10m (rule/for)
  9 |   for: 13m
 
-level=info msg="Problems found" Bug=2
+rules/0001.yml:10 Bug: this alert rule must have a 'for' field with a minimum duration of 5m (rule/for)
+ 10 | - alert: none
+
+level=info msg="Problems found" Bug=3
 level=fatal msg="Fatal error" error="found 1 problem(s) with severity Bug or higher"
 -- rules/0001.yml --
 - alert: ok
@@ -22,6 +25,8 @@ level=fatal msg="Fatal error" error="found 1 problem(s) with severity Bug or hig
 - alert: 13m
   expr: up == 0
   for: 13m
+- alert: none
+  expr: up == 0
 
 -- .pint.hcl --
 parser {

cmd/pint/tests/0142_keep_firing_for.txt

@@ -0,0 +1,15 @@
+pint.ok --no-color lint rules
+! stdout .
+cmp stderr stderr.txt
+
+-- stderr.txt --
+level=info msg="Loading configuration file" path=.pint.hcl
+-- rules/0001.yml --
+- alert: Instance Is Down 1
+  expr: up == 0
+  keep_firing_for: 5m
+
+-- .pint.hcl --
+parser {
+  relaxed = [".*"]
+}

cmd/pint/tests/0143_keep_firing_for.txt

@@ -0,0 +1,41 @@
+pint.error --no-color lint rules
+! stdout .
+cmp stderr stderr.txt
+
+-- stderr.txt --
+level=info msg="Loading configuration file" path=.pint.hcl
+rules/0001.yml:6 Bug: this alert rule must have a 'keep_firing_for' field with a minimum duration of 5m (rule/for)
+ 6 |   keep_firing_for: 3m
+
+rules/0001.yml:9 Bug: this alert rule must have a 'keep_firing_for' field with a maximum duration of 10m (rule/for)
+ 9 |   keep_firing_for: 13m
+
+rules/0001.yml:10 Bug: this alert rule must have a 'keep_firing_for' field with a minimum duration of 5m (rule/for)
+ 10 | - alert: none
+
+level=info msg="Problems found" Bug=3
+level=fatal msg="Fatal error" error="found 1 problem(s) with severity Bug or higher"
+-- rules/0001.yml --
+- alert: ok
+  expr: up == 0
+  keep_firing_for: 5m
+- alert: 3m
+  expr: up == 0
+  keep_firing_for: 3m
+- alert: 13m
+  expr: up == 0
+  keep_firing_for: 13m
+- alert: none
+  expr: up == 0
+
+-- .pint.hcl --
+parser {
+  relaxed = [".*"]
+}
+rule {
+  keep_firing_for {
+    severity = "bug"
+    min      = "5m"
+    max      = "10m"
+  }
+}

docs/changelog.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v0.46.0
+
+### Added
+
+- Added support for `keep_firing_for` in alerting rules - #713.
+- Added `rule/keep_firing_for` check - #713.
+- Added `alerts/count` check will now estimate alerts using
+  `keep_firing_for` field if set - #713.
+- Configuration rule `match` block supports a new filter `keep_firing_for`.
+
 ## v0.45.0
 
 ### Added

docs/checks/alerts/count.md

@@ -9,7 +9,7 @@ grand_parent: Documentation
 This check is used to estimate how many times given alert would fire.
 It will run `expr` query from every alert rule against selected Prometheus
 servers and report how many unique alerts it would generate.
-If `for` is set on alerts it will be used to adjust results.
+If `for` and/or `keep_firing_for` are set on alerts they will be used to adjust results.
 
 ## Configuration
 

docs/checks/alerts/for.md

@@ -6,8 +6,8 @@ grand_parent: Documentation
 
 # alerts/for
 
-This check will warn if an alert rule uses invalid `for` value
-or if it passes default value that can be removed to simplify rule.
+This check will warn if an alert rule uses invalid `for` or `keep_firing_for`
+value or if it passes default value that can be removed to simplify rule.
 
 ## Configuration
 

docs/checks/rule/for.md

@@ -6,21 +6,24 @@ grand_parent: Documentation
 
 # rule/for
 
-This check allows to enforce the presence of `for` field on alerting
-rules.
+This check allows to enforce the presence of `for` or `keep_firing_for` field
+on alerting rules.
 You can configure it to enforce some minimal and/or maximum duration
-set on alerts via `for` field.
+set on alerts via `for` and/or `keep_firing_for` fields.
 
 ## Configuration
 
 This check doesn't have any configuration options.
 
 ## How to enable it
 
+This check uses either `for` or `keep_firing_for` configuration
+blocks, depending on which alerting rule field you want to enforce.
+
 Syntax:
 
 ```js
-for {
+for|keep_firing_for {
   severity = "bug|warning|info"
   min      = "5m"
   max      = "10m"
@@ -33,6 +36,42 @@ for {
 - `max` - maximum allowed `for` value for matching alerting rules.
 - If not set maximum `for` duration won't be enforced.
 
+Example:
+
+Enforce that all alerts have `for` fields of `5m` or more:
+
+```js
+for {
+  severity = "bug"
+  min      = "5m"
+  max      = "10m"
+}
+```
+
+Enforce that all alerts have `keep_firing_for` fields with no more than `1h`:
+
+```js
+keep_firing_for {
+  severity = "bug"
+  max      = "1h"
+}
+```
+
+To enforce both at the same time:
+
+```js
+for {
+  severity = "bug"
+  min      = "5m"
+  max      = "10m"
+}
+
+keep_firing_for {
+  severity = "bug"
+  max      = "1h"
+}
+```
+
 ## How to disable it
 
 You can disable this check globally by adding this config block:

docs/configuration.md

@@ -388,6 +388,8 @@ rule {
   field present and matching provided value will be checked by this rule. Recording rules
   will never match it as they don't have `for` field.
   Syntax is `OP DURATION` where `OP` can be any of `=`, `!=`, `>`, `>=`, `<`, `<=`.
+- `match:keep_firing_for` - optional alerting rule `keep_firing_for` filter. Works the same
+  way as `for` match filter.
 - `ignore` - works exactly like `match` but does the opposite - any alerting or recording rule
   matching all conditions defined on `ignore` will not be checked by this `rule` block.
 
@@ -433,3 +435,12 @@ rule {
   [ check applied only to alerting rules with "for" field value that is >= 5m ]
 }
 ```
+
+```js
+rule {
+  match {
+    keep_firing_for = "> 15m"
+  }
+  [ check applied only to alerting rules with "keep_firing_for" field value that is > 15m ]
+}
+```

internal/checks/alerts_count.go

@@ -89,10 +89,15 @@ func (c AlertsCheck) Check(ctx context.Context, _ string, rule parser.Rule, _ []
 	if rule.AlertingRule.For != nil {
 		forDur, _ = model.ParseDuration(rule.AlertingRule.For.Value.Value)
 	}
+	var keepFiringForDur model.Duration
+	if rule.AlertingRule.KeepFiringFor != nil {
+		keepFiringForDur, _ = model.ParseDuration(rule.AlertingRule.KeepFiringFor.Value.Value)
+	}
 
 	var alerts int
 	for _, r := range qr.Series.Ranges {
-		if r.End.Sub(r.Start) > time.Duration(forDur) {
+		// If `keepFiringFor` is not defined its Duration will be 0
+		if r.End.Sub(r.Start) > (time.Duration(forDur) + time.Duration(keepFiringForDur)) {
 			alerts++
 		}
 	}
@@ -106,6 +111,9 @@ func (c AlertsCheck) Check(ctx context.Context, _ string, rule parser.Rule, _ []
 	if rule.AlertingRule.For != nil {
 		lines = append(lines, rule.AlertingRule.For.Lines()...)
 	}
+	if rule.AlertingRule.KeepFiringFor != nil {
+		lines = append(lines, rule.AlertingRule.KeepFiringFor.Lines()...)
+	}
 	sort.Ints(lines)
 
 	delta := qr.Series.Until.Sub(qr.Series.From)

internal/checks/alerts_count_test.go

@@ -645,6 +645,150 @@ func TestAlertsCountCheck(t *testing.T) {
 				},
 			},
 		},
+		{
+			description: "keep_firing_for: 10m",
+			content:     "- alert: Foo Is Down\n  keep_firing_for: 10m\n  expr: up{job=\"foo\"} == 0\n",
+			checker:     newAlertsCheck,
+			prometheus:  newSimpleProm,
+			problems: func(uri string) []checks.Problem {
+				return []checks.Problem{
+					{
+						Fragment: `up{job="foo"} == 0`,
+						Lines:    []int{2, 3},
+						Reporter: "alerts/count",
+						Text:     alertsText("prom", uri, 2, "1d"),
+						Severity: checks.Information,
+					},
+				}
+			},
+			mocks: []*prometheusMock{
+				{
+					conds: []requestCondition{
+						requireRangeQueryPath,
+						formCond{key: "query", value: `up{job="foo"} == 0`},
+					},
+					resp: matrixResponse{
+						samples: []*model.SampleStream{
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-24),
+								time.Now().Add(time.Hour*-24).Add(time.Minute*6),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-23),
+								time.Now().Add(time.Hour*-23).Add(time.Minute*6),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-22),
+								time.Now().Add(time.Hour*-22).Add(time.Minute),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-21),
+								time.Now().Add(time.Hour*-21).Add(time.Minute*16),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-20),
+								time.Now().Add(time.Hour*-20).Add(time.Minute*9).Add(time.Second*59),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-18),
+								time.Now().Add(time.Hour*-18).Add(time.Hour*2),
+								time.Minute,
+							),
+						},
+					},
+				},
+				{
+					conds: []requestCondition{
+						requireRangeQueryPath,
+						formCond{key: "query", value: `count(up)`},
+					},
+					resp: respondWithSingleRangeVector1D(),
+				},
+			},
+		},
+		{
+			description: "for: 10m + keep_firing_for: 10m",
+			content:     "- alert: Foo Is Down\n  for: 10m\n  keep_firing_for: 10m\n  expr: up{job=\"foo\"} == 0\n",
+			checker:     newAlertsCheck,
+			prometheus:  newSimpleProm,
+			problems: func(uri string) []checks.Problem {
+				return []checks.Problem{
+					{
+						Fragment: `up{job="foo"} == 0`,
+						Lines:    []int{2, 3, 4},
+						Reporter: "alerts/count",
+						Text:     alertsText("prom", uri, 1, "1d"),
+						Severity: checks.Information,
+					},
+				}
+			},
+			mocks: []*prometheusMock{
+				{
+					conds: []requestCondition{
+						requireRangeQueryPath,
+						formCond{key: "query", value: `up{job="foo"} == 0`},
+					},
+					resp: matrixResponse{
+						samples: []*model.SampleStream{
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-24),
+								time.Now().Add(time.Hour*-24).Add(time.Minute*6),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-23),
+								time.Now().Add(time.Hour*-23).Add(time.Minute*6),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-22),
+								time.Now().Add(time.Hour*-22).Add(time.Minute),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-21),
+								time.Now().Add(time.Hour*-21).Add(time.Minute*16),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-20),
+								time.Now().Add(time.Hour*-20).Add(time.Minute*9).Add(time.Second*59),
+								time.Minute,
+							),
+							generateSampleStream(
+								map[string]string{"job": "foo"},
+								time.Now().Add(time.Hour*-18),
+								time.Now().Add(time.Hour*-18).Add(time.Hour*2),
+								time.Minute,
+							),
+						},
+					},
+				},
+				{
+					conds: []requestCondition{
+						requireRangeQueryPath,
+						formCond{key: "query", value: `count(up)`},
+					},
+					resp: respondWithSingleRangeVector1D(),
+				},
+			},
+		},
 	}
 
 	runTests(t, testCases)