Improve logging of NewType (#1249)

Before this change, `NewType(nil)` would return a unhelpful error
message:

```
Unsupported type '<nil>' of value: <nil> in /quesma/clickhouse/schema.go:273
```

Improve the log by providing the "origin" of the `nil` value (in most
cases the column name with that `nil` value).

Author: avelanarius

quesma/clickhouse/parser.go

@@ -156,7 +156,7 @@ func BuildAttrsMap(m SchemaMap, config *ChTableConfig) (map[string][]interface{}
 			if a.Type.CanConvert(value) {
 				result[a.KeysArrayName] = append(result[a.KeysArrayName], name)
 				result[a.ValuesArrayName] = append(result[a.ValuesArrayName], fmt.Sprintf("%v", value))
-				result[a.TypesArrayName] = append(result[a.TypesArrayName], NewType(value).String())
+				result[a.TypesArrayName] = append(result[a.TypesArrayName], NewType(value, name).String())
 
 				matched = true
 				break

quesma/clickhouse/schema.go

@@ -231,7 +231,7 @@ func ResolveType(clickHouseTypeName string) reflect.Type {
 }
 
 // 'value': value of a field, from unmarshalled JSON
-func NewType(value any) Type {
+func NewType(value any, valueOrigin string) Type {
 	isFloatInt := func(f float64) bool {
 		return math.Mod(f, 1.0) == 0.0
 	}
@@ -258,7 +258,7 @@ func NewType(value any) Type {
 		cols := make([]*Column, len(valueCasted))
 		for k, v := range valueCasted {
 			if v != nil {
-				cols = append(cols, &Column{Name: k, Type: NewType(v), Codec: Codec{Name: ""}})
+				cols = append(cols, &Column{Name: k, Type: NewType(v, fmt.Sprintf("%s.%s", valueOrigin, k)), Codec: Codec{Name: ""}})
 			}
 		}
 		return MultiValueType{Name: "Tuple", Cols: cols}
@@ -267,10 +267,10 @@ func NewType(value any) Type {
 			// empty array defaults to string for now, maybe change needed or error returned
 			return CompoundType{Name: "Array", BaseType: NewBaseType("String")}
 		}
-		return CompoundType{Name: "Array", BaseType: NewType(valueCasted[0])}
+		return CompoundType{Name: "Array", BaseType: NewType(valueCasted[0], fmt.Sprintf("%s[0]", valueOrigin))}
 	}
 
-	logger.Warn().Msgf("Unsupported type '%T' of value: %v.", value, value)
+	logger.Warn().Msgf("Unsupported type '%T' of value: %v (origin: %s).", value, value, valueOrigin)
 
 	// value can be nil, so should return something reasonable here
 	return BaseType{Name: "String", GoType: reflect.TypeOf("")}

quesma/ingest/parser.go

@@ -94,7 +94,7 @@ func JsonToColumns(m SchemaMap, chConfig *clickhouse.ChTableConfig) []CreateTabl
 		if value == nil { // HACK ALERT -> We're treating null values as strings for now, so that we don't completely discard documents with empty values
 			fTypeString = "Nullable(String)"
 		} else {
-			fType := clickhouse.NewType(value)
+			fType := clickhouse.NewType(value, name)
 
 			// handle "field":{} case (Elastic Agent sends such JSON fields) by ignoring them
 			if multiValueType, ok := fType.(clickhouse.MultiValueType); ok && len(multiValueType.Cols) == 0 {
@@ -315,7 +315,7 @@ func BuildAttrsMap(m SchemaMap, config *clickhouse.ChTableConfig) (map[string][]
 			if a.Type.CanConvert(value) {
 				result[a.KeysArrayName] = append(result[a.KeysArrayName], name)
 				result[a.ValuesArrayName] = append(result[a.ValuesArrayName], fmt.Sprintf("%v", value))
-				result[a.TypesArrayName] = append(result[a.TypesArrayName], clickhouse.NewType(value).String())
+				result[a.TypesArrayName] = append(result[a.TypesArrayName], clickhouse.NewType(value, name).String())
 
 				matched = true
 				break

quesma/ingest/processor.go

@@ -258,7 +258,7 @@ func addInvalidJsonFieldsToAttributes(attrsMap map[string][]interface{}, invalid
 	for k, v := range invalidJson {
 		newAttrsMap[chLib.DeprecatedAttributesKeyColumn] = append(newAttrsMap[chLib.DeprecatedAttributesKeyColumn], k)
 		newAttrsMap[chLib.DeprecatedAttributesValueColumn] = append(newAttrsMap[chLib.DeprecatedAttributesValueColumn], v)
-		newAttrsMap[chLib.DeprecatedAttributesValueType] = append(newAttrsMap[chLib.DeprecatedAttributesValueType], chLib.NewType(v).String())
+		newAttrsMap[chLib.DeprecatedAttributesValueType] = append(newAttrsMap[chLib.DeprecatedAttributesValueType], chLib.NewType(v, k).String())
 	}
 	return newAttrsMap
 }