use is nullable from override mappings

dbGen/config.go

@@ -2,6 +2,7 @@ package dbGen
 
 import (
 	"fmt"
+	"github.com/guregu/null/v5"
 	"github.com/keenmate/db-gen/common"
 	"github.com/spf13/viper"
 	"os"
@@ -56,13 +57,16 @@ type ColumnMapping struct {
 	MappedName      string `mapstructure:"MappedName"`
 	MappedType      string `mapstructure:"MappedType"`
 	MappingFunction string `mapstructure:"MappingFunction"`
-	IsNullable      bool   `mapstructure:"IsNullable"`
+
+	IsNullable null.Bool `mapstructure:"IsNullable"`
 }
 
 type ParamMapping struct {
-	IsNullable bool   `mapstructure:"IsNullable"`
 	MappedName string `mapstructure:"MappedName"`
 	MappedType string `mapstructure:"MappedType"`
+
+	// this is string because it can be empty
+	IsNullable null.Bool `mapstructure:"IsNullable"`
 }
 
 type Mapping struct {

dbGen/configMapper.go

@@ -2,6 +2,7 @@ package dbGen
 
 import (
 	"fmt"
+	"github.com/guregu/null/v5"
 	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/viper"
 	"reflect"
@@ -46,6 +47,9 @@ func mapCustomTypes() mapstructure.DecodeHookFunc {
 		if to == reflect.TypeOf(map[string]ColumnMapping{}) {
 			return decodeColumnMapping(data)
 		}
+		if to == reflect.TypeOf(null.Bool{}) {
+			return decodeNullBool(data)
+		}
 
 		return data, nil
 	}
@@ -109,3 +113,10 @@ func decodeColumnMapping(data interface{}) (interface{}, error) {
 
 	return columns, nil
 }
+
+func decodeNullBool(data interface{}) (interface{}, error) {
+	if reflect.TypeOf(data).Kind() == reflect.Bool {
+		return null.BoolFrom(data.(bool)), nil
+	}
+	return null.NewBool(false, false), nil
+}

dbGen/mapper.go

@@ -2,6 +2,7 @@ package dbGen
 
 import (
 	"fmt"
+	"github.com/guregu/null/v5"
 	"github.com/keenmate/db-gen/common"
 	"github.com/stoewer/go-strcase"
 	"slices"
@@ -118,7 +119,7 @@ func mapReturnColumns(routine DbRoutine, typeMappings *map[string]mapping, routi
 			PropertyType:   typeMapping.mappedType,
 			Position:       column.OrdinalPosition - positionOffset,
 			MapperFunction: typeMapping.mappedFunction,
-			Nullable:       column.IsNullable,
+			Nullable:       getIsNullable(columnMapping.IsNullable, column.IsNullable),
 		}
 
 		properties = append(properties, *property)
@@ -145,8 +146,8 @@ func mapParameters(attributes []DbParameter, typeMappings *map[string]mapping, r
 	//common.LogDebug("Possition offset is %d", positionOffset)
 
 	for i, parameter := range attributes {
-		paramMapping := getParamMapping(parameter.Name, routineMapping)
-
+		paramMapping := getParamMapping(parameter, routineMapping)
+		common.LogDebug("parameter %s custom mapping: %+v", parameter.Name, paramMapping)
 		propertyName := getPropertyName(parameter.Name, paramMapping.MappedName)
 
 		typeMapping, err := getTypeMapping(parameter.UDTName, paramMapping.MappedType, "", typeMappings, config)
@@ -160,8 +161,8 @@ func mapParameters(attributes []DbParameter, typeMappings *map[string]mapping, r
 			PropertyName:   propertyName,
 			PropertyType:   typeMapping.mappedType,
 			Position:       parameter.OrdinalPosition - positionOffset,
-			MapperFunction: typeMapping.mappedFunction,
-			Nullable:       parameter.IsNullable,
+			MapperFunction: "",
+			Nullable:       getIsNullable(paramMapping.IsNullable, parameter.IsNullable),
 		}
 
 		properties[i] = *property
@@ -244,6 +245,7 @@ func handleMappingOverride(typeOverride string, mappingFunctionOverride string,
 			}, nil
 		}
 	}
+
 	// no mapping function is set and no mapping exist for type given
 	return nil, fmt.Errorf("mapped type overriden to %s, but no mapping functions specified and mapping function for override type doenst exist in mappings", typeOverride)
 }
@@ -263,7 +265,6 @@ func getRoutineMapping(routine DbRoutine, schemaConfigs map[string]SchemaConfig)
 		// this should never happen
 		panic("trying ty get function mapping for function in schema that is not defined. This should never happen, because function should have been fitered out")
 	}
-
 	routineMapping, found := schemaConfig.Functions[routine.RoutineNameWithParams]
 	if found {
 		return routineMapping
@@ -282,7 +283,7 @@ var emptyColumnMapping = ColumnMapping{
 	MappedName:      "",
 	MappedType:      "",
 	MappingFunction: "",
-	IsNullable:      false,
+	IsNullable:      null.NewBool(false, false),
 }
 
 func getColumnMapping(columnName string, routineMapping *RoutineMapping) (bool, ColumnMapping) {
@@ -303,16 +304,25 @@ func getColumnMapping(columnName string, routineMapping *RoutineMapping) (bool,
 var emptyParamMapping = ParamMapping{
 	MappedName: "",
 	MappedType: "",
-	IsNullable: false,
+	IsNullable: null.NewBool(false, false),
 }
 
-func getParamMapping(paramName string, routineMapping *RoutineMapping) ParamMapping {
+func getParamMapping(param DbParameter, routineMapping *RoutineMapping) ParamMapping {
 
-	columnMapping, hasExplicitParamMapping := routineMapping.Parameters[paramName]
+	columnMapping, hasExplicitParamMapping := routineMapping.Parameters[param.Name]
 	if hasExplicitParamMapping {
 		return columnMapping
 	}
 
 	return emptyParamMapping
 
 }
+
+func getIsNullable(typeMappingOverride null.Bool, implicitValue bool) bool {
+	if typeMappingOverride.Valid {
+		common.LogDebug("using explicit value of nullable %t", typeMappingOverride.Bool)
+		return typeMappingOverride.Bool
+	}
+
+	return implicitValue
+}

go.mod

@@ -1,6 +1,8 @@
 module github.com/keenmate/db-gen
 
-go 1.21
+go 1.21.4
+
+toolchain go1.21.9
 
 require (
 	github.com/jackc/pgx/v5 v5.5.1
@@ -12,6 +14,7 @@ require (
 
 require (
 	github.com/fsnotify/fsnotify v1.6.0 // indirect
+	github.com/guregu/null/v5 v5.0.0 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect

go.sum

@@ -122,6 +122,8 @@ github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/googleapis/google-cloud-go-testing v0.0.0-20200911160855-bcd43fbb19e8/go.mod h1:dvDLG8qkwmyD9a/MJJN3XJcT3xFxOKAvTZGvuZmac9g=
+github.com/guregu/null/v5 v5.0.0 h1:PRxjqyOekS11W+w/7Vfz6jgJE/BCwELWtgvOJzddimw=
+github.com/guregu/null/v5 v5.0.0/go.mod h1:SjupzNy+sCPtwQTKWhUCqjhVCO69hpsl2QsZrWHjlwU=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=

testing/db-gen.json

@@ -20,13 +20,14 @@
 					"SelectOnlySpecified": true,
 					"Model": {
 						"__number": {
-							"MappedType": "int"
+							"MappedType": "int",
+							"IsNullable": true
 						},
 						"__json": {
 							"MappedName": "jason",
 							"MappedType": "string",
 							"MappingFunction": "mapJsonAsString",
-							"IsNullable": false
+							"IsNullable": null
 						}
 					}
 				},