fix(inputs.snmp): Translate field correctly when not in table (#15618)

internal/snmp/field.go

@@ -95,6 +95,17 @@ func (f *Field) Init(tr Translator) error {
 
 // fieldConvert converts from any type according to the conv specification
 func (f *Field) Convert(ent gosnmp.SnmpPDU) (interface{}, error) {
+	// snmptranslate table field value here
+	if f.Translate {
+		if entOid, ok := ent.Value.(string); ok {
+			_, _, oidText, _, err := f.translator.SnmpTranslate(entOid)
+			if err == nil {
+				// If no error translating, the original value for ent.Value should be replaced
+				ent.Value = oidText
+			}
+		}
+	}
+
 	if f.Conversion == "" {
 		// OctetStrings may contain hex data that needs its own conversion
 		if ent.Type == gosnmp.OctetString && !utf8.Valid(ent.Value.([]byte)[:]) {

internal/snmp/table.go

@@ -205,17 +205,6 @@ func (t Table) Build(gs Connection, walk bool) (*RTable, error) {
 					}, idx)
 				}
 
-				// snmptranslate table field value here
-				if f.Translate {
-					if entOid, ok := ent.Value.(string); ok {
-						_, _, oidText, _, err := t.translator.SnmpTranslate(entOid)
-						if err == nil {
-							// If no error translating, the original value for ent.Value should be replaced
-							ent.Value = oidText
-						}
-					}
-				}
-
 				fv, err := f.Convert(ent)
 				if err != nil {
 					return &walkError{

internal/snmp/translator_gosmi_test.go

@@ -274,15 +274,21 @@ func TestTableBuild_noWalkGosmi(t *testing.T) {
 				Name: "noexist",
 				Oid:  ".1.2.3.4.5",
 			},
+			{
+				Name:      "myfield4",
+				Oid:       ".1.3.6.1.2.1.3.1.1.3.0",
+				Translate: true,
+			},
 		},
 	}
 
+	require.NoError(t, tbl.Init(getGosmiTr(t)))
 	tb, err := tbl.Build(tsc, false)
 	require.NoError(t, err)
 
 	rtr := RTableRow{
 		Tags:   map[string]string{"myfield1": "baz", "myfield3": "234"},
-		Fields: map[string]interface{}{"myfield2": 234},
+		Fields: map[string]interface{}{"myfield2": 234, "myfield4": "atNetAddress"},
 	}
 	require.Len(t, tb.Rows, 1)
 	require.Contains(t, tb.Rows, rtr)

internal/snmp/translator_netsnmp_test.go

@@ -207,15 +207,21 @@ func TestTableBuild_noWalk(t *testing.T) {
 				Name: "noexist",
 				Oid:  ".1.2.3.4.5",
 			},
+			{
+				Name:      "myfield4",
+				Oid:       ".1.0.0.0.1.6.0",
+				Translate: true,
+			},
 		},
 	}
 
+	require.NoError(t, tbl.Init(NewNetsnmpTranslator(testutil.Logger{})))
 	tb, err := tbl.Build(tsc, false)
 	require.NoError(t, err)
 
 	rtr := RTableRow{
 		Tags:   map[string]string{"myfield1": "baz", "myfield3": "234"},
-		Fields: map[string]interface{}{"myfield2": 234},
+		Fields: map[string]interface{}{"myfield2": 234, "myfield4": "testTableEntry.7"},
 	}
 	require.Len(t, tb.Rows, 1)
 	require.Contains(t, tb.Rows, rtr)