| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package ddsnmp |
| 4 | |
| 5 | import ( |
| 6 | "fmt" |
| 7 | "slices" |
| 8 | "strings" |
| 9 | |
| 10 | "github.com/netdata/netdata/go/plugins/plugin/go.d/collector/snmp/ddsnmp/ddprofiledefinition" |
| 11 | ) |
| 12 | |
| 13 | // HandleCrossTableTagsWithoutMetrics is the exported entry point for callers outside |
| 14 | // this package (notably tests in ddsnmpcollector) that need to prepare a profile in |
| 15 | // isolation, without the additional enrichment performed by FinalizeProfiles. |
| 16 | func HandleCrossTableTagsWithoutMetrics(prof *Profile) { |
| 17 | handleCrossTableTagsWithoutMetrics(prof) |
| 18 | } |
| 19 | |
| 20 | // handleCrossTableTagsWithoutMetrics ensures tables referenced only by cross-table tags |
| 21 | // are still walked during collection. Without this, if a table like ifXTable is used |
| 22 | // only for cross-table tags (e.g., getting interface names) but has no metrics defined, |
| 23 | // it won't be walked and the tags will be missing. This creates synthetic metric entries |
| 24 | // for such tables using the longest common OID prefix of the referenced columns, including |
| 25 | // lookup columns used by value-based joins. |
| 26 | func handleCrossTableTagsWithoutMetrics(prof *Profile) { |
| 27 | if prof.Definition == nil { |
| 28 | return |
| 29 | } |
| 30 | |
| 31 | handleCrossTableTagsWithoutMetricsForRows(&prof.Definition.Metrics) |
| 32 | handleCrossTableTagsWithoutMetricsForTopologyRows(&prof.Definition.Topology) |
| 33 | } |
| 34 | |
| 35 | func handleCrossTableTagsWithoutMetricsForRows(metrics *[]ddprofiledefinition.MetricsConfig) { |
| 36 | seenTableNames := make(map[string]bool) |
| 37 | for _, m := range *metrics { |
| 38 | seenTableNames[m.Table.Name] = true |
| 39 | } |
| 40 | |
| 41 | tagCrossTableOnlyOIDs := crossTableOnlyTagOIDs(*metrics, seenTableNames) |
| 42 | for tableName, oids := range tagCrossTableOnlyOIDs { |
| 43 | *metrics = append(*metrics, syntheticCrossTableMetric(tableName, oids)) |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | func handleCrossTableTagsWithoutMetricsForTopologyRows(topology *[]ddprofiledefinition.TopologyConfig) { |
| 48 | seenTableNames := make(map[string]bool) |
| 49 | for _, topo := range *topology { |
| 50 | seenTableNames[topo.Table.Name] = true |
| 51 | } |
| 52 | |
| 53 | for i := range *topology { |
| 54 | topo := &(*topology)[i] |
| 55 | tagCrossTableOnlyOIDs := crossTableOnlyTagOIDs([]ddprofiledefinition.MetricsConfig{topo.MetricsConfig}, seenTableNames) |
| 56 | for tableName, oids := range tagCrossTableOnlyOIDs { |
| 57 | *topology = append(*topology, ddprofiledefinition.TopologyConfig{ |
| 58 | Kind: topo.Kind, |
| 59 | MetricsConfig: syntheticCrossTableMetric(tableName, oids), |
| 60 | }) |
| 61 | seenTableNames[tableName] = true |
| 62 | } |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | func crossTableOnlyTagOIDs(metrics []ddprofiledefinition.MetricsConfig, seenTableNames map[string]bool) map[string][]string { |
| 67 | tagCrossTableOnlyOIDs := make(map[string][]string) |
| 68 | for _, m := range metrics { |
| 69 | if m.IsScalar() { |
| 70 | continue |
| 71 | } |
| 72 | for _, tag := range m.MetricTags { |
| 73 | if tag.Table == "" || seenTableNames[tag.Table] { |
| 74 | continue |
| 75 | } |
| 76 | if tag.Symbol.OID != "" { |
| 77 | tagCrossTableOnlyOIDs[tag.Table] = append(tagCrossTableOnlyOIDs[tag.Table], tag.Symbol.OID) |
| 78 | } |
| 79 | if tag.LookupSymbol.OID != "" { |
| 80 | tagCrossTableOnlyOIDs[tag.Table] = append(tagCrossTableOnlyOIDs[tag.Table], tag.LookupSymbol.OID) |
| 81 | } |
| 82 | } |
| 83 | } |
| 84 | return tagCrossTableOnlyOIDs |
| 85 | } |
| 86 | |
| 87 | func syntheticCrossTableMetric(tableName string, oids []string) ddprofiledefinition.MetricsConfig { |
| 88 | slices.Sort(oids) |
| 89 | oids = slices.Compact(oids) |
| 90 | |
| 91 | return ddprofiledefinition.MetricsConfig{ |
| 92 | MIB: fmt.Sprintf("synthetic-%s-MIB", tableName), |
| 93 | Table: ddprofiledefinition.SymbolConfig{ |
| 94 | OID: longestCommonPrefix(oids), |
| 95 | Name: tableName, |
| 96 | }, |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | func longestCommonPrefix(oids []string) string { |
| 101 | if len(oids) == 0 { |
| 102 | return "" |
| 103 | } |
| 104 | |
| 105 | prefixParts := splitOIDParts(oids[0]) |
| 106 | for i := 1; i < len(oids); i++ { |
| 107 | parts := splitOIDParts(oids[i]) |
| 108 | n := min(len(parts), len(prefixParts)) |
| 109 | |
| 110 | j := 0 |
| 111 | for j < n && prefixParts[j] == parts[j] { |
| 112 | j++ |
| 113 | } |
| 114 | prefixParts = prefixParts[:j] |
| 115 | if len(prefixParts) == 0 { |
| 116 | return "" |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | return strings.Join(prefixParts, ".") |
| 121 | } |
| 122 | |
| 123 | func splitOIDParts(oid string) []string { |
| 124 | parts := strings.Split(strings.Trim(oid, "."), ".") |
| 125 | if len(parts) == 1 && parts[0] == "" { |
| 126 | return nil |
| 127 | } |
| 128 | return parts |
| 129 | } |