generator/tree.go: Add support for subsequent address family in combi… (

#782)

* generator/tree.go: Add support for subsequent address family in combined type

Since some MIB carry information about Safi (subsequent address family),
it will cause the generator to bail out, even though there is a valid Subtype before.

E.g.
Afi
Safi
Address

This is especially valid for Juniper BGP MIB.

Link: https://learningnetwork.cisco.com/s/question/0D53i00000KssMOCAZ/bgp-afi-and-safi

Signed-off-by: Josef Johansson <josef86@gmail.com>

* Update generator/tree.go

Signed-off-by: Ben Kochie <superq@gmail.com>

---------

Signed-off-by: Josef Johansson <josef86@gmail.com>
Signed-off-by: Ben Kochie <superq@gmail.com>
Co-authored-by: Ben Kochie <superq@gmail.com>

generator/tree.go

@@ -360,7 +360,10 @@ func generateConfigModule(cfg *ModuleConfig, node *Node, nameToNode map[string]*
 				return // Ignored metric.
 			}
 
+			// Afi (Address family)
 			prevType := ""
+			// Safi (Subsequent address family, e.g. Multicast/Unicast)
+			prev2Type := ""
 			for count, i := range n.Indexes {
 				index := &config.Index{Labelname: i}
 				indexNode, ok := nameToNode[i]
@@ -383,11 +386,14 @@ func generateConfigModule(cfg *ModuleConfig, node *Node, nameToNode map[string]*
 				if subtype, ok := combinedTypes[index.Type]; ok {
 					if prevType == subtype {
 						metric.Indexes = metric.Indexes[:len(metric.Indexes)-1]
+					} else if prev2Type == subtype {
+						metric.Indexes = metric.Indexes[:len(metric.Indexes)-2]
 					} else {
 						level.Warn(logger).Log("msg", "Can't handle index type on node, missing preceding", "node", n.Label, "type", index.Type, "missing", subtype)
 						return
 					}
 				}
+				prev2Type = prevType
 				prevType = indexNode.TextualConvention
 				metric.Indexes = append(metric.Indexes, index)
 			}