Implement parse relationship architecture

clause/clause.go

@@ -59,7 +59,7 @@ type OverrideNameInterface interface {
 type Where struct {
 	AndConditions AddConditions
 	ORConditions  []ORConditions
-	Builders      []Expression
+	builders      []Expression
 }
 
 func (where Where) Name() string {
@@ -74,8 +74,8 @@ func (where Where) Build(builder Builder) {
 		where.AndConditions.Build(builder)
 	}
 
-	if len(where.Builders) > 0 {
+	if len(where.builders) > 0 {
-		for _, b := range where.Builders {
+		for _, b := range where.builders {
 			if withConditions {
 				builder.Write(" AND ")
 			}
@@ -122,9 +122,9 @@ func (where Where) MergeExpression(expr Expression) {
 	if w, ok := expr.(Where); ok {
 		where.AndConditions = append(where.AndConditions, w.AndConditions...)
 		where.ORConditions = append(where.ORConditions, w.ORConditions...)
-		where.Builders = append(where.Builders, w.Builders...)
+		where.builders = append(where.builders, w.builders...)
 	} else {
-		where.Builders = append(where.Builders, expr)
+		where.builders = append(where.builders, expr)
 	}
 }
 
@@ -135,6 +135,22 @@ type Select struct {
 
 // Join join clause
 type Join struct {
+	Table    string
+	Type     string // left join books on
+	ON       []Expression
+	builders []Expression
+}
+
+func (join Join) Build(builder Builder) {
+	// TODO
+}
+
+func (join Join) MergeExpression(expr Expression) {
+	if j, ok := expr.(Join); ok {
+		join.builders = append(join.builders, j.builders...)
+	} else {
+		join.builders = append(join.builders, expr)
+	}
 }
 
 // GroupBy group by clause

clause/query.go

@@ -2,6 +2,12 @@ package clause
 
 import "strings"
 
+// Column quote with name
+type Column struct {
+	Table string
+	Name  string
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Query Expressions
 ////////////////////////////////////////////////////////////////////////////////

schema/field.go

@@ -8,10 +8,10 @@ import (
 	"time"
 )
 
-type FieldType string
+type DataType string
 
 const (
-	Bool   FieldType = "bool"
+	Bool   DataType = "bool"
 	Int             = "int"
 	Uint            = "uint"
 	Float           = "float"
@@ -24,7 +24,7 @@ type Field struct {
 	Name            string
 	DBName          string
 	BindNames       []string
-	DataType        FieldType
+	DataType        DataType
 	DBDataType      string
 	PrimaryKey      bool
 	AutoIncrement   bool
@@ -42,8 +42,7 @@ type Field struct {
 	Tag             reflect.StructTag
 	TagSettings     map[string]string
 	Schema          *Schema
-	EmbeddedbSchema *Schema
+	EmbeddedSchema  *Schema
-	Relationship    string
 }
 
 func (schema *Schema) ParseField(fieldStruct reflect.StructField) *Field {
@@ -177,8 +176,8 @@ func (schema *Schema) ParseField(fieldStruct reflect.StructField) *Field {
 	}
 
 	if _, ok := field.TagSettings["EMBEDDED"]; ok || fieldStruct.Anonymous {
-		field.EmbeddedbSchema = Parse(fieldValue, sync.Map{}, schema.namer)
+		field.EmbeddedSchema, schema.err = Parse(fieldValue, sync.Map{}, schema.namer)
-		for _, ef := range field.EmbeddedbSchema.Fields {
+		for _, ef := range field.EmbeddedSchema.Fields {
 			ef.BindNames = append([]string{fieldStruct.Name}, ef.BindNames...)
 
 			if prefix, ok := field.TagSettings["EMBEDDED_PREFIX"]; ok {
@@ -189,13 +188,6 @@ func (schema *Schema) ParseField(fieldStruct reflect.StructField) *Field {
 				ef.TagSettings[k] = v
 			}
 		}
-	} else {
-		switch fieldValue.Kind() {
-		case reflect.Struct:
-			field.Relationship = "one"
-		case reflect.Slice:
-			field.Relationship = "many"
-		}
 	}
 
 	return field

schema/naming.go

@@ -10,8 +10,10 @@ import (
 
 // Namer namer interface
 type Namer interface {
-	TableName(string) string
+	TableName(table string) string
-	ColumnName(string) string
+	ColumnName(column string) string
+	JoinTableName(table string) string
+	JoinTableColumnName(table, column string) string
 }
 
 // NamingStrategy tables, columns naming strategy
@@ -33,6 +35,16 @@ func (ns NamingStrategy) ColumnName(str string) string {
 	return toDBName(str)
 }
 
+// JoinTableName convert string to join table name
+func (ns NamingStrategy) JoinTableName(str string) string {
+	return ns.TablePrefix + toDBName(str)
+}
+
+// JoinTableColumnName convert string to join table column name
+func (ns NamingStrategy) JoinTableColumnName(referenceTable, referenceColumn string) string {
+	return inflection.Singular(toDBName(referenceTable)) + toDBName(referenceColumn)
+}
+
 var (
 	smap sync.Map
 	// https://github.com/golang/lint/blob/master/lint.go#L770

schema/relationship.go

@@ -1,43 +1,143 @@
 package schema
 
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
 // RelationshipType relationship type
 type RelationshipType string
 
 const (
-	HasOneRel    RelationshipType = "has_one"      // HasOneRel has one relationship
+	HasOne    RelationshipType = "has_one"      // HasOneRel has one relationship
-	HasManyRel   RelationshipType = "has_many"     // HasManyRel has many relationship
+	HasMany   RelationshipType = "has_many"     // HasManyRel has many relationship
-	BelongsToRel RelationshipType = "belongs_to"   // BelongsToRel belongs to relationship
+	BelongsTo RelationshipType = "belongs_to"   // BelongsToRel belongs to relationship
-	Many2ManyRel RelationshipType = "many_to_many" // Many2ManyRel many to many relationship
+	Many2Many RelationshipType = "many_to_many" // Many2ManyRel many to many relationship
 )
 
 type Relationships struct {
-	HasOne    map[string]*Relationship
+	HasOne    []*Relationship
-	BelongsTo map[string]*Relationship
+	BelongsTo []*Relationship
-	HasMany   map[string]*Relationship
+	HasMany   []*Relationship
-	Many2Many map[string]*Relationship
+	Many2Many []*Relationship
+	Relations map[string]*Relationship
 }
 
 type Relationship struct {
+	Name                                string
 	Type                                RelationshipType
-	ForeignKeys            []*RelationField // self
+	Field                               *Field
-	AssociationForeignKeys []*RelationField // association
+	Polymorphic                         *Polymorphic
-	JoinTable              *JoinTable
+	References                          []Reference
+	Schema                              *Schema
+	FieldSchema                         *Schema
+	JoinTable                           *Schema
+	ForeignKeys, AssociationForeignKeys []string
 }
 
-type RelationField struct {
+type Polymorphic struct {
-	*Field
+	PolymorphicID   *Field
-	PolymorphicField *Field
+	PolymorphicType *Field
-	PolymorphicValue string
+	Value           string
 }
 
-type JoinTable struct {
+type Reference struct {
-	Table                  string
+	PriamryKey    *Field
-	ForeignKeys            []*RelationField
+	PriamryValue  string
-	AssociationForeignKeys []*RelationField
+	ForeignKey    *Field
+	OwnPriamryKey bool
 }
 
-func (schema *Schema) buildToOneRel(field *Field) {
+func (schema *Schema) parseRelation(field *Field) {
+	var (
+		fieldValue = reflect.New(field.FieldType).Interface()
+		relation   = &Relationship{
+			Name:                   field.Name,
+			Field:                  field,
+			Schema:                 schema,
+			Type:                   RelationshipType(strings.ToLower(strings.TrimSpace(field.TagSettings["REL"]))),
+			ForeignKeys:            toColumns(field.TagSettings["FOREIGNKEY"]),
+			AssociationForeignKeys: toColumns(field.TagSettings["ASSOCIATION_FOREIGNKEY"]),
+		}
+	)
+
+	if relation.FieldSchema, schema.err = Parse(fieldValue, schema.cacheStore, schema.namer); schema.err != nil {
+		return
 	}
 
-func (schema *Schema) buildToManyRel(field *Field) {
+	// User has many Toys, its `Polymorphic` is `Owner`, Pet has one Toy, its `Polymorphic` is `Owner`
+	//     type User struct {
+	//       Toys []Toy `gorm:"polymorphic:Owner;"`
+	//     }
+	//     type Pet struct {
+	//       Toy Toy `gorm:"polymorphic:Owner;"`
+	//     }
+	//     type Toy struct {
+	//       OwnerID   int
+	//       OwnerType string
+	//     }
+	if polymorphic, _ := field.TagSettings["POLYMORPHIC"]; polymorphic != "" {
+		relation.Polymorphic = &Polymorphic{
+			Value:           schema.Table,
+			PolymorphicType: relation.FieldSchema.FieldsByName[polymorphic+"Type"],
+			PolymorphicID:   relation.FieldSchema.FieldsByName[polymorphic+"ID"],
+		}
+
+		if value, ok := field.TagSettings["POLYMORPHIC_VALUE"]; ok {
+			relation.Polymorphic.Value = strings.TrimSpace(value)
+		}
+
+		if relation.Polymorphic.PolymorphicType == nil {
+			schema.err = fmt.Errorf("invalid polymorphic type: %v for %v on field %v, missing field %v", relation.FieldSchema, schema, field.Name, polymorphic+"Type")
+		}
+
+		if relation.Polymorphic.PolymorphicID == nil {
+			schema.err = fmt.Errorf("invalid polymorphic type: %v for %v on field %v, missing field %v", relation.FieldSchema, schema, field.Name, polymorphic+"ID")
+		}
+
+		if schema.err == nil {
+			relation.References = append(relation.References, Reference{
+				PriamryValue: relation.Polymorphic.Value,
+				ForeignKey:   relation.Polymorphic.PolymorphicType,
+			})
+
+			primaryKeyField := schema.PrioritizedPrimaryField
+			if len(relation.ForeignKeys) > 0 {
+				if primaryKeyField = schema.LookUpField(relation.ForeignKeys[0]); primaryKeyField == nil || len(relation.ForeignKeys) > 1 {
+					schema.err = fmt.Errorf("invalid polymorphic foreign key: %+v for %v on field %v", relation.ForeignKeys, schema, field.Name)
+				}
+			}
+			relation.References = append(relation.References, Reference{
+				PriamryKey:    primaryKeyField,
+				ForeignKey:    relation.Polymorphic.PolymorphicType,
+				OwnPriamryKey: true,
+			})
+		}
+
+		switch field.FieldType.Kind() {
+		case reflect.Struct:
+			relation.Type = HasOne
+		case reflect.Slice:
+			relation.Type = HasMany
+		}
+		return
+	}
+
+	switch field.FieldType.Kind() {
+	case reflect.Struct:
+		schema.parseStructRelation(relation, field)
+	case reflect.Slice:
+		schema.parseSliceRelation(relation, field)
+	default:
+		schema.err = fmt.Errorf("unsupported data type: %v (in %v#%v ", field.FieldType.PkgPath(), schema, field.Name)
+	}
+}
+
+func (schema *Schema) parseStructRelation(relation *Relationship, field *Field) error {
+	return nil
+}
+
+func (schema *Schema) parseSliceRelation(relation *Relationship, field *Field) error {
+	return nil
 }

schema/schema.go

@@ -1,6 +1,7 @@
 package schema
 
 import (
+	"fmt"
 	"go/ast"
 	"reflect"
 	"strings"
@@ -8,6 +9,7 @@ import (
 )
 
 type Schema struct {
+	Name                    string
 	ModelType               reflect.Type
 	Table                   string
 	PrioritizedPrimaryField *Field
@@ -16,42 +18,64 @@ type Schema struct {
 	FieldsByName            map[string]*Field
 	FieldsByDBName          map[string]*Field
 	Relationships           Relationships
+	err                     error
 	namer                   Namer
+	cacheStore              sync.Map
+}
+
+func (schema Schema) String() string {
+	return schema.ModelType.PkgPath()
+}
+
+func (schema Schema) LookUpField(name string) *Field {
+	if field, ok := schema.FieldsByDBName[name]; ok {
+		return field
+	}
+	if field, ok := schema.FieldsByName[name]; ok {
+		return field
+	}
+	return nil
 }
 
 // get data type from dialector
-func Parse(dest interface{}, cacheStore sync.Map, namer Namer) *Schema {
+func Parse(dest interface{}, cacheStore sync.Map, namer Namer) (*Schema, error) {
 	modelType := reflect.ValueOf(dest).Type()
 	for modelType.Kind() == reflect.Slice || modelType.Kind() == reflect.Ptr {
 		modelType = modelType.Elem()
 	}
 
 	if modelType.Kind() != reflect.Struct {
-		return nil
+		if modelType.PkgPath() == "" {
+			return nil, fmt.Errorf("unsupported data %+v when parsing model", dest)
+		}
+		return nil, fmt.Errorf("unsupported data type %v when parsing model", modelType.PkgPath())
 	}
 
 	if v, ok := cacheStore.Load(modelType); ok {
-		return v.(*Schema)
+		return v.(*Schema), nil
 	}
 
 	schema := &Schema{
+		Name:           modelType.Name(),
 		ModelType:      modelType,
 		Table:          namer.TableName(modelType.Name()),
 		FieldsByName:   map[string]*Field{},
 		FieldsByDBName: map[string]*Field{},
+		cacheStore:     cacheStore,
 	}
 
+	defer func() {
+		if schema.err != nil {
+			cacheStore.Delete(modelType)
+		}
+	}()
+
 	for i := 0; i < modelType.NumField(); i++ {
-		fieldStruct := modelType.Field(i)
+		if fieldStruct := modelType.Field(i); ast.IsExported(fieldStruct.Name) {
-		if !ast.IsExported(fieldStruct.Name) {
-			continue
-		}
-
 			field := schema.ParseField(fieldStruct)
 			schema.Fields = append(schema.Fields, field)
-		if field.EmbeddedbSchema != nil {
+			if field.EmbeddedSchema != nil {
-			for _, f := range field.EmbeddedbSchema.Fields {
+				schema.Fields = append(schema.Fields, field.EmbeddedSchema.Fields...)
-				schema.Fields = append(schema.Fields, f)
 			}
 		}
 	}
@@ -85,7 +109,12 @@ func Parse(dest interface{}, cacheStore sync.Map, namer Namer) *Schema {
 			}
 			schema.PrimaryFields = append(schema.PrimaryFields, field)
 		}
+
+		if field.DataType == "" {
+			defer schema.parseRelation(field)
+		}
 	}
 
-	return schema
+	cacheStore.Store(modelType, schema)
+	return schema, schema.err
 }

schema/utils.go

@@ -29,3 +29,12 @@ func checkTruth(val string) bool {
 	}
 	return true
 }
+
+func toColumns(val string) (results []string) {
+	if val != "" {
+		for _, v := range strings.Split(val, ",") {
+			results = append(results, strings.TrimSpace(v))
+		}
+	}
+	return
+}