Added support for gorm.datatypes.JSON field

docs/docs/models.md

@@ -59,6 +59,10 @@ Those types are not supported yet, but will be in the future:
 
 `models.SliceField` can be used to store slices, that are encoded to JSON string for storage (implement sql.Scanner and driver.Valuer interfaces). In request and response JSON payloads, the slice is represented as a JSON array. The types of the slice need to be golang built-in basic types. The field provides validation of all the elements in the slice.
 
+### JSON fields
+
+`datatypes.JSON` from `gorm.datatypes` package can be used to store JSON data in a database, in JSON column type native to the database. The field is represented as a JSON object in the request and response JSON payloads.
+
 ## Model relations
 
 GRF models by themselves do not directly support relations, but:

go.mod

@@ -14,24 +14,26 @@ require (
 	github.com/shopspring/decimal v1.3.1
 	github.com/sirupsen/logrus v1.9.3
 	github.com/stretchr/testify v1.10.0
+	gorm.io/datatypes v1.2.5
 	gorm.io/driver/postgres v1.5.11
 	gorm.io/driver/sqlite v1.5.2
 	gorm.io/gorm v1.25.12
 )
 
 require (
+	filippo.io/edwards25519 v1.1.0 // indirect
 	github.com/bytedance/sonic v1.12.8 // indirect
 	github.com/bytedance/sonic/loader v0.2.3 // indirect
-	github.com/chenzhuoyu/base64x v0.0.0-20230717121745-296ad89f973d // indirect
 	github.com/cloudwego/base64x v0.1.5 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/gabriel-vasile/mimetype v1.4.8 // indirect
 	github.com/gin-contrib/sse v1.0.0 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-sql-driver/mysql v1.8.1 // indirect
 	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
-	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
+	github.com/jackc/pgservicefile v0.0.0-20231201235250-de7065d80cb9 // indirect
 	github.com/jackc/pgx/v5 v5.5.5 // indirect
 	github.com/jackc/puddle/v2 v2.2.1 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
@@ -60,4 +62,5 @@ require (
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	google.golang.org/protobuf v1.36.5 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
+	gorm.io/driver/mysql v1.5.6 // indirect
 )

pkg/detectors/attributes.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/glothriel/grf/pkg/fields"
 	"github.com/glothriel/grf/pkg/models"
+	"gorm.io/datatypes"
 )
 
 // Prints a summary with the fields of the model obtained using reflection
@@ -56,7 +57,8 @@ type fieldSettings struct {
 
 	isGRFRepresentable bool
 	isGRFParsable      bool
-	isForeignKey       bool
+	isRelation         bool
+	isDataTypesJSON    bool
 
 	isSqlNullInt32 bool
 }
@@ -84,6 +86,7 @@ func getFieldSettings[Model any](fieldName string) *fieldSettings {
 			_, isGRFRepresentable := theTypeAsAny.(fields.GRFRepresentable)
 			_, isGRFParsable := theTypeAsAny.(fields.GRFParsable)
 			_, isSQLNull32 := theTypeAsAny.(*sql.NullInt32)
+			_, isDataTypesJSON := theTypeAsAny.(*datatypes.JSON)
 
 			settings = &fieldSettings{
 				itsType: reflect.TypeOf(
@@ -93,7 +96,8 @@ func getFieldSettings[Model any](fieldName string) *fieldSettings {
 				isEncodingTextUnmarshaler: isEncodingTextUnmarshaler,
 				isGRFRepresentable:        isGRFRepresentable,
 				isGRFParsable:             isGRFParsable,
-				isForeignKey:              fieldMarkedAsRelation,
+				isRelation:                fieldMarkedAsRelation,
+				isDataTypesJSON:           isDataTypesJSON,
 				isSqlNullInt32:            isSQLNull32,
 			}
 		}

pkg/detectors/detectors.go

@@ -16,7 +16,7 @@ type relationshipDetector[Model any] struct {
 
 func (p *relationshipDetector[Model]) ToInternalValue(fieldName string) (fields.InternalValueFunc, error) {
 	fieldSettings := getFieldSettings[Model](fieldName)
-	if fieldSettings.isForeignKey {
+	if fieldSettings.isRelation {
 		return nil, ErrFieldShouldBeSkipped
 	}
 	return p.internalChild.ToInternalValue(fieldName)
@@ -28,7 +28,7 @@ func (p *relationshipDetector[Model]) ToRepresentation(fieldName string) (fields
 		return nil, fmt.Errorf("Field `%s` is not present in the model", fieldName)
 
 	}
-	if fieldSettings.isForeignKey {
+	if fieldSettings.isRelation {
 		return nil, ErrFieldShouldBeSkipped
 	}
 	return p.representationChild.ToRepresentation(fieldName)

pkg/detectors/internal.go

@@ -3,13 +3,15 @@ package detectors
 import (
 	"database/sql"
 	"encoding"
+	"encoding/json"
 	"fmt"
 	"reflect"
 	"time"
 
 	"github.com/gin-gonic/gin"
 	"github.com/glothriel/grf/pkg/fields"
 	"github.com/glothriel/grf/pkg/types"
+	"gorm.io/datatypes"
 )
 
 type ToInternalValueDetector interface {
@@ -108,6 +110,29 @@ func (p *encodingTextUnmarshalerToInternalValueDetector[Model]) ToInternalValue(
 	return nil, fmt.Errorf("Field `%s` is not a encoding.TextUnmarshaler", fieldName)
 }
 
+type gormDataTypesJSONToInternalValueDetector[Model any] struct{}
+
+func (p *gormDataTypesJSONToInternalValueDetector[Model]) ToInternalValue(fieldName string) (fields.InternalValueFunc, error) {
+	fieldSettings := getFieldSettings[Model](fieldName)
+	if fieldSettings.isDataTypesJSON {
+		return ConvertFuncToInternalValueFuncAdapter(
+			func(v any) (any, error) {
+				vAsBytes, marshalErr := json.Marshal(v)
+				if marshalErr != nil {
+					return nil, fmt.Errorf("Failed to marshal field `%s` to JSON: %w", fieldName, marshalErr)
+				}
+				var dtj datatypes.JSON
+				unmarshalErr := dtj.UnmarshalJSON(vAsBytes)
+				if unmarshalErr != nil {
+					return nil, fmt.Errorf("Failed to unmarshal field `%s` from JSON: %w", fieldName, unmarshalErr)
+				}
+				return dtj, nil
+			},
+		), nil
+	}
+	return nil, fmt.Errorf("Field `%s` is not a encoding.TextUnmarshaler", fieldName)
+}
+
 type usingSqlNullFieldToInternalValueDetector[Model any, sqlNullType any] struct {
 	valueFunc func(v any) (any, error)
 }
@@ -168,6 +193,7 @@ func DefaultToInternalValueDetector[Model any]() ToInternalValueDetector {
 				children: []ToInternalValueDetector{
 					&usingGRFParsableToInternalValueDetector[Model]{},
 					&isoTimeTimeToInternalValueDetector[Model]{},
+					&gormDataTypesJSONToInternalValueDetector[Model]{},
 					&fromTypeMapperToInternalValueDetector[Model]{
 						mapper:         types.Mapper(),
 						modelTypeNames: FieldTypes[Model](),

pkg/detectors/representation.go

@@ -3,6 +3,7 @@ package detectors
 import (
 	"database/sql"
 	"encoding"
+	"encoding/json"
 	"fmt"
 	"reflect"
 	"time"
@@ -11,6 +12,7 @@ import (
 	"github.com/glothriel/grf/pkg/fields"
 	"github.com/glothriel/grf/pkg/models"
 	"github.com/glothriel/grf/pkg/types"
+	"gorm.io/datatypes"
 )
 
 // ToRepresentationDetector is an interface that allows to detect the representation function for a given field
@@ -26,6 +28,7 @@ func DefaultToRepresentationDetector[Model any]() ToRepresentationDetector[Model
 				children: []ToRepresentationDetector[Model]{
 					&usingGRFRepresentableToRepresentationProvider[Model]{},
 					&timeTimeToRepresentationProvider[Model]{},
+					&gormDataTypesJSONToRepresentationProvider[Model]{},
 					&fromTypeMapperToRepresentationProvider[Model]{
 						mapper:         types.Mapper(),
 						modelTypeNames: FieldTypes[Model](),
@@ -213,6 +216,33 @@ func (p encodingTextMarshalerToRepresentationProvider[Model]) ToRepresentation(f
 	return nil, fmt.Errorf("Field `%s` is not a encoding.TextMarshaler", fieldName)
 }
 
+type gormDataTypesJSONToRepresentationProvider[Model any] struct{}
+
+func (p gormDataTypesJSONToRepresentationProvider[Model]) ToRepresentation(fieldName string) (fields.RepresentationFunc, error) {
+	fieldSettings := getFieldSettings[Model](fieldName)
+	if fieldSettings != nil && fieldSettings.isDataTypesJSON {
+		return ConvertFuncToRepresentationFuncAdapter(
+			func(v any) (any, error) {
+				vAsJSON, ok := v.(datatypes.JSON)
+				if !ok {
+					return nil, fmt.Errorf("Field `%s` is not a datatypes.JSON", fieldName)
+				}
+				rawJSON, marshalJSONErr := vAsJSON.MarshalJSON()
+				if marshalJSONErr != nil {
+					return nil, fmt.Errorf("Failed to marshal field `%s` to JSON: %w", fieldName, marshalJSONErr)
+				}
+				var ret any
+				unmarshalErr := json.Unmarshal(rawJSON, &ret)
+				if unmarshalErr != nil {
+					return nil, fmt.Errorf("Failed to unmarshal field `%s` from JSON: %w", fieldName, unmarshalErr)
+				}
+				return ret, nil
+			},
+		), nil
+	}
+	return nil, fmt.Errorf("Field `%s` is not a encoding.TextMarshaler", fieldName)
+}
+
 type chainingToRepresentationDetector[Model any] struct {
 	children []ToRepresentationDetector[Model]
 }

pkg/integration/fields_test.go

@@ -14,6 +14,7 @@ import (
 	"github.com/shopspring/decimal"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
+	"gorm.io/datatypes"
 	"gorm.io/driver/postgres"
 	"gorm.io/driver/sqlite"
 	"gorm.io/gorm"
@@ -93,6 +94,11 @@ type NullFloat64Model struct {
 	Value sql.NullFloat64 `json:"value" gorm:"column:value"`
 }
 
+type NestedJSONModel struct {
+	models.BaseModel
+	Value datatypes.JSON `json:"value" gorm:"column:value"`
+}
+
 func DoTestTypes(t *testing.T, dialector gorm.Dialector) { // nolint: funlen
 	tests := []struct {
 		name        string
@@ -438,6 +444,31 @@ func DoTestTypes(t *testing.T, dialector gorm.Dialector) { // nolint: funlen
 				return registerModel[NullFloat64Model]("/null_float64_field", dialector)
 			},
 		},
+		{
+			name:    "Nested JSON field",
+			baseURL: "/nested_json_field",
+			okBodies: []map[string]any{
+				{"value": map[string]string{"foo": "bar"}},
+				{"value": []int{1, 2, 3}},
+				{"value": []bool{true, false}},
+				{"value": true},
+				{"value": "hello world"},
+				{"value": "1,337"},
+				{"value": "1.3.37"},
+			},
+			okResponses: []map[string]any{
+				{"value": map[string]any{"foo": "bar"}},
+				{"value": []any{1.0, 2.0, 3.0}},
+				{"value": []any{true, false}},
+				{"value": true},
+				{"value": "hello world"},
+				{"value": "1,337"},
+				{"value": "1.3.37"},
+			},
+			router: func() *gin.Engine {
+				return registerModel[NestedJSONModel]("/nested_json_field", dialector)
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {