feat: generate unsigned integer type (go-gorm#426)

* feat: generate unsigned integer type

* feat: field signable

* docs: field signable

README.ZH_CN.md

@@ -167,6 +167,8 @@ func main() {
         /* FieldNullable: true,*/
         //if you want to assign field which has default value in `Create` API, set FieldCoverable true, reference: https://gorm.io/docs/create.html#Default-Values
         /* FieldCoverable: true,*/
+        // if you want generate field with unsigned integer type, set FieldSignable true
+        /* FieldSignable: true,*/
         //if you want to generate index tags from database, set FieldWithIndexTag true
         /* FieldWithIndexTag: true,*/
         //if you want to generate type tags from database, set FieldWithTypeTag true

README.md

@@ -169,6 +169,8 @@ func main() {
         /* FieldNullable: true,*/
         //if you want to assign field which has default value in `Create` API, set FieldCoverable true, reference: https://gorm.io/docs/create.html#Default-Values
         /* FieldCoverable: true,*/
+        // if you want generate field with unsigned integer type, set FieldSignable true
+        /* FieldSignable: true,*/
         //if you want to generate index tags from database, set FieldWithIndexTag true
         /* FieldWithIndexTag: true,*/
         //if you want to generate type tags from database, set FieldWithTypeTag true

config.go

@@ -5,10 +5,11 @@ import (
 	"path/filepath"
 	"strings"
 
-	"gorm.io/gen/internal/check"
-	"gorm.io/gen/internal/model"
 	"gorm.io/gorm"
 	"gorm.io/gorm/utils/tests"
+
+	"gorm.io/gen/internal/check"
+	"gorm.io/gen/internal/model"
 )
 
 type GenerateMode uint
@@ -33,6 +34,7 @@ type Config struct {
 	// generate model global configuration
 	FieldNullable     bool // generate pointer when field is nullable
 	FieldCoverable    bool // generate pointer when field has default value, to fix problem zero value cannot be assign: https://gorm.io/docs/create.html#Default-Values
+	FieldSignable     bool // detect integer field's unsigned type, adjust generated data type
 	FieldWithIndexTag bool // generate with gorm index tag
 	FieldWithTypeTag  bool // generate with gorm column type tag
 

generator.go

@@ -123,6 +123,7 @@ func (g *Generator) GenerateModelAs(tableName string, modelName string, fieldOpt
 		FieldConf: model.FieldConf{
 			DataTypeMap: g.dataTypeMap,
 
+			FieldSignable:     g.FieldSignable,
 			FieldNullable:     g.FieldNullable,
 			FieldCoverable:    g.FieldCoverable,
 			FieldWithIndexTag: g.FieldWithIndexTag,

internal/check/gen_structs.go

@@ -81,7 +81,7 @@ func GenBaseStruct(db *gorm.DB, conf model.Conf) (base *BaseStruct, err error) {
 		col.SetDataTypeMap(conf.DataTypeMap)
 		col.WithNS(conf.FieldJSONTagNS, conf.FieldNewTagNS)
 
-		m := col.ToField(conf.FieldNullable, conf.FieldCoverable)
+		m := col.ToField(conf.FieldNullable, conf.FieldCoverable, conf.FieldSignable)
 
 		if filterField(m, filterOpts) == nil {
 			continue

internal/model/base.go

@@ -78,9 +78,9 @@ func (g *KeyWords) Contain(text string) bool {
 var (
 	defaultDataType             = "string"
 	dataType        dataTypeMap = map[string]dataTypeMapping{
-		"int":        func(string) string { return "int32" },
 		"numeric":    func(string) string { return "int32" },
 		"integer":    func(string) string { return "int32" },
+		"int":        func(string) string { return "int32" },
 		"smallint":   func(string) string { return "int32" },
 		"mediumint":  func(string) string { return "int32" },
 		"bigint":     func(string) string { return "int64" },

internal/model/conf.go

@@ -10,6 +10,7 @@ type FieldConf struct {
 
 	FieldNullable     bool // generate pointer when field is nullable
 	FieldCoverable    bool // generate pointer when field has default value
+	FieldSignable     bool // detect integer field's unsigned type, adjust generated data type
 	FieldWithIndexTag bool // generate with gorm index tag
 	FieldWithTypeTag  bool // generate with gorm column type tagl
 

internal/model/tbl_column.go

@@ -43,8 +43,11 @@ func (c *Column) WithNS(jsonTagNS, newTagNS func(columnName string) string) {
 	}
 }
 
-func (c *Column) ToField(nullable, coverable bool) *Field {
+func (c *Column) ToField(nullable, coverable, signable bool) *Field {
 	fieldType := c.GetDataType()
+	if signable && strings.Contains(c.columnType(), "unsigned") && strings.HasPrefix(fieldType, "int") {
+		fieldType = "u" + fieldType
+	}
 	switch {
 	case c.Name() == "deleted_at" && fieldType == "time.Time":
 		fieldType = "gorm.DeletedAt"
@@ -55,19 +58,22 @@ func (c *Column) ToField(nullable, coverable bool) *Field {
 	case coverable && c.withDefaultValue():
 		fieldType = "*" + fieldType
 	}
-	f := &Field{
+
+	var comment string
+	if c, ok := c.Comment(); ok {
+		comment = c
+	}
+
+	return &Field{
 		Name:             c.Name(),
 		Type:             fieldType,
 		ColumnName:       c.Name(),
 		MultilineComment: c.multilineComment(),
 		GORMTag:          c.buildGormTag(),
 		JSONTag:          c.jsonTagNS(c.Name()),
 		NewTag:           c.newTagNS(c.Name()),
+		ColumnComment:    comment,
 	}
-	if c, ok := c.Comment(); ok {
-		f.ColumnComment = c
-	}
-	return f
 }
 
 func (c *Column) multilineComment() bool {