cloudflare/pint
Publicmirrored from https://github.com/cloudflare/pintAvailable
internal/checks/alerts_comparison.go
91lines · modecode
| 1 | package checks |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | |
| 6 | "github.com/cloudflare/pint/internal/discovery" |
| 7 | "github.com/cloudflare/pint/internal/parser" |
| 8 | |
| 9 | promParser "github.com/prometheus/prometheus/promql/parser" |
| 10 | ) |
| 11 | |
| 12 | const ( |
| 13 | ComparisonCheckName = "alerts/comparison" |
| 14 | ) |
| 15 | |
| 16 | func NewComparisonCheck() ComparisonCheck { |
| 17 | return ComparisonCheck{} |
| 18 | } |
| 19 | |
| 20 | type ComparisonCheck struct{} |
| 21 | |
| 22 | func (c ComparisonCheck) String() string { |
| 23 | return ComparisonCheckName |
| 24 | } |
| 25 | |
| 26 | func (c ComparisonCheck) Reporter() string { |
| 27 | return ComparisonCheckName |
| 28 | } |
| 29 | |
| 30 | func (c ComparisonCheck) Check(ctx context.Context, rule parser.Rule, entries []discovery.Entry) (problems []Problem) { |
| 31 | if rule.AlertingRule == nil { |
| 32 | return |
| 33 | } |
| 34 | |
| 35 | if rule.AlertingRule.Expr.SyntaxError != nil { |
| 36 | return |
| 37 | } |
| 38 | |
| 39 | if isAbsent(rule.Expr().Query) { |
| 40 | return |
| 41 | } |
| 42 | |
| 43 | if expr := hasComparision(rule.Expr().Query); expr != nil { |
| 44 | if expr.ReturnBool { |
| 45 | problems = append(problems, Problem{ |
| 46 | Fragment: rule.AlertingRule.Expr.Value.Value, |
| 47 | Lines: rule.AlertingRule.Expr.Lines(), |
| 48 | Reporter: c.Reporter(), |
| 49 | Text: "alert query uses bool modifier for comparison, this means it will always return a result and the alert will always fire", |
| 50 | Severity: Bug, |
| 51 | }) |
| 52 | } |
| 53 | return |
| 54 | } |
| 55 | |
| 56 | problems = append(problems, Problem{ |
| 57 | Fragment: rule.AlertingRule.Expr.Value.Value, |
| 58 | Lines: rule.AlertingRule.Expr.Lines(), |
| 59 | Reporter: c.Reporter(), |
| 60 | Text: "alert query doesn't have any condition, it will always fire if the metric exists", |
| 61 | Severity: Warning, |
| 62 | }) |
| 63 | |
| 64 | return |
| 65 | } |
| 66 | |
| 67 | func hasComparision(n *parser.PromQLNode) *promParser.BinaryExpr { |
| 68 | if node, ok := n.Node.(*promParser.BinaryExpr); ok { |
| 69 | if node.Op.IsComparisonOperator() { |
| 70 | return node |
| 71 | } |
| 72 | if node.Op == promParser.LUNLESS { |
| 73 | return node |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | for _, child := range n.Children { |
| 78 | if node := hasComparision(child); node != nil { |
| 79 | return node |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | return nil |
| 84 | } |
| 85 | |
| 86 | func isAbsent(n *parser.PromQLNode) bool { |
| 87 | if node, ok := n.Node.(*promParser.Call); ok && (node.Func.Name == "absent") { |
| 88 | return true |
| 89 | } |
| 90 | return false |
| 91 | } |
| 92 | |