| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package program |
| 4 | |
| 5 | import ( |
| 6 | "errors" |
| 7 | "fmt" |
| 8 | ) |
| 9 | |
| 10 | // SelectorMatcher is the runtime predicate compiled from selector expressions. |
| 11 | // |
| 12 | // Implementations are expected to be immutable and safe for concurrent reads. |
| 13 | type SelectorMatcher interface { |
| 14 | Matches(metricName string, labels SelectorLabels) bool |
| 15 | } |
| 16 | |
| 17 | // SelectorLabels is the minimal read-only label view required by selector |
| 18 | // matchers. metrix.LabelView satisfies this interface. |
| 19 | type SelectorLabels interface { |
| 20 | Len() int |
| 21 | Get(key string) (string, bool) |
| 22 | Range(fn func(key, value string) bool) |
| 23 | } |
| 24 | |
| 25 | // SelectorBinding stores selector expression + compiled runtime matcher metadata. |
| 26 | type SelectorBinding struct { |
| 27 | // Expression is original selector text (for diagnostics/debugging). |
| 28 | Expression string |
| 29 | // Matcher is compiled selector predicate. |
| 30 | Matcher SelectorMatcher |
| 31 | // MetricNames are normalized metric-name constraints extracted from selector. |
| 32 | MetricNames []string |
| 33 | // ConstrainedLabelKeys are matcher keys (sorted/unique) used by label policies. |
| 34 | ConstrainedLabelKeys []string |
| 35 | } |
| 36 | |
| 37 | // Dimension is one compiled dimension mapping rule for a chart. |
| 38 | type Dimension struct { |
| 39 | Selector SelectorBinding |
| 40 | |
| 41 | // NameTemplate is used for static/dynamic dimension rendering. |
| 42 | NameTemplate Template |
| 43 | // NameFromLabel is explicit dynamic name source in placeholder-free mode. |
| 44 | NameFromLabel string |
| 45 | // InferNameFromSeriesMeta requests runtime inference based on series origin |
| 46 | // metadata (e.g. histogram/state-set flatten semantics). |
| 47 | InferNameFromSeriesMeta bool |
| 48 | |
| 49 | // Hidden maps to DIMENSION hidden option. |
| 50 | Hidden bool |
| 51 | // Multiplier maps to DIMENSION multiplier option. |
| 52 | Multiplier int |
| 53 | // Divisor maps to DIMENSION divisor option. |
| 54 | Divisor int |
| 55 | // Float maps to DIMENSION type=float option. |
| 56 | Float bool |
| 57 | // Dynamic is compile-derived and true when rendering can fan out by labels. |
| 58 | Dynamic bool |
| 59 | } |
| 60 | |
| 61 | func validateDimension(dimension Dimension) error { |
| 62 | var errs []error |
| 63 | if dimension.Selector.Expression == "" { |
| 64 | errs = append(errs, fmt.Errorf("selector expression is required")) |
| 65 | } |
| 66 | if dimension.Selector.Matcher == nil { |
| 67 | errs = append(errs, fmt.Errorf("selector matcher is required")) |
| 68 | } |
| 69 | if dimension.NameTemplate.Raw == "" && dimension.NameFromLabel == "" && !dimension.InferNameFromSeriesMeta { |
| 70 | errs = append(errs, fmt.Errorf("dimension name is required (name template or name_from_label)")) |
| 71 | } |
| 72 | return errors.Join(errs...) |
| 73 | } |
| 74 | |
| 75 | func (d Dimension) clone() Dimension { |
| 76 | out := d |
| 77 | out.Selector = d.Selector.clone() |
| 78 | out.NameTemplate = d.NameTemplate.clone() |
| 79 | return out |
| 80 | } |
| 81 | |
| 82 | func (s SelectorBinding) clone() SelectorBinding { |
| 83 | out := s |
| 84 | // Matcher instance is immutable compiled program and can be shared. |
| 85 | out.MetricNames = append([]string(nil), s.MetricNames...) |
| 86 | out.ConstrainedLabelKeys = append([]string(nil), s.ConstrainedLabelKeys...) |
| 87 | return out |
| 88 | } |