gorm/scope.go

409 lines
10 KiB
Go

package gorm
import (
"errors"
"fmt"
"go/ast"
"strings"
"time"
"reflect"
"regexp"
)
type Scope struct {
Value interface{}
indirectValue *reflect.Value
Search *search
Sql string
SqlVars []interface{}
db *DB
_values map[string]interface{}
skipLeft bool
primaryKey string
}
func (scope *Scope) IndirectValue() reflect.Value {
if scope.indirectValue == nil {
value := reflect.Indirect(reflect.ValueOf(scope.Value))
scope.indirectValue = &value
}
return *scope.indirectValue
}
// NewScope create scope for callbacks, including DB's search information
func (db *DB) NewScope(value interface{}) *Scope {
db.Value = value
return &Scope{db: db, Search: db.search, Value: value, _values: map[string]interface{}{}}
}
// New create a new Scope without search information
func (scope *Scope) New(value interface{}) *Scope {
return &Scope{db: scope.db.parent, Search: &search{}, Value: value}
}
// NewDB create a new DB without search information
func (scope *Scope) NewDB() *DB {
return scope.db.new()
}
// DB get *sql.DB
func (scope *Scope) DB() sqlCommon {
return scope.db.db
}
// SkipLeft skip remaining callbacks
func (scope *Scope) SkipLeft() {
scope.skipLeft = true
}
// Quote used to quote database column name according to database dialect
func (scope *Scope) Quote(str string) string {
return scope.Dialect().Quote(str)
}
// Dialect get dialect
func (scope *Scope) Dialect() Dialect {
return scope.db.parent.dialect
}
// Err write error
func (scope *Scope) Err(err error) error {
if err != nil {
scope.db.err(err)
}
return err
}
// Log print log message
func (scope *Scope) Log(v ...interface{}) {
scope.db.log(v...)
}
// HasError check if there are any error
func (scope *Scope) HasError() bool {
return scope.db.Error != nil
}
// PrimaryKey get the primary key's column name
func (scope *Scope) PrimaryKey() string {
if scope.primaryKey != "" {
return scope.primaryKey
}
scope.primaryKey = ToSnake(GetPrimaryKey(scope.Value))
return scope.primaryKey
}
// PrimaryKeyZero check the primary key is blank or not
func (scope *Scope) PrimaryKeyZero() bool {
return isBlank(reflect.ValueOf(scope.PrimaryKeyValue()))
}
// PrimaryKeyValue get the primary key's value
func (scope *Scope) PrimaryKeyValue() interface{} {
if scope.IndirectValue().Kind() == reflect.Struct {
if field := scope.IndirectValue().FieldByName(SnakeToUpperCamel(scope.PrimaryKey())); field.IsValid() {
return field.Interface()
}
}
return 0
}
// HasColumn to check if has column
func (scope *Scope) HasColumn(name string) bool {
_, result := scope.FieldValueByName(name)
return result
}
// FieldValueByName to get column's value and existence
func (scope *Scope) FieldValueByName(name string) (interface{}, bool) {
return FieldValueByName(name, scope.Value)
}
// SetColumn to set the column's value
func (scope *Scope) SetColumn(column string, value interface{}) bool {
if scope.Value == nil {
return false
}
return setFieldValue(scope.IndirectValue().FieldByName(SnakeToUpperCamel(column)), value)
}
// CallMethod invoke method with necessary argument
func (scope *Scope) CallMethod(name string) {
if scope.Value == nil {
return
}
call := func(value interface{}) {
if fm := reflect.ValueOf(value).MethodByName(name); fm.IsValid() {
fi := fm.Interface()
if f, ok := fi.(func()); ok {
f()
} else if f, ok := fi.(func(s *Scope)); ok {
f(scope)
} else if f, ok := fi.(func(s *DB)); ok {
f(scope.db.new())
} else if f, ok := fi.(func() error); ok {
scope.Err(f())
} else if f, ok := fi.(func(s *Scope) error); ok {
scope.Err(f(scope))
} else if f, ok := fi.(func(s *DB) error); ok {
scope.Err(f(scope.db.new()))
} else {
scope.Err(errors.New(fmt.Sprintf("unsupported function %v", name)))
}
}
}
if values := scope.IndirectValue(); values.Kind() == reflect.Slice {
for i := 0; i < values.Len(); i++ {
call(values.Index(i).Addr().Interface())
}
} else {
call(scope.Value)
}
}
// AddToVars add value as sql's vars, gorm will escape them
func (scope *Scope) AddToVars(value interface{}) string {
scope.SqlVars = append(scope.SqlVars, value)
return scope.Dialect().BinVar(len(scope.SqlVars))
}
// TableName get table name
var pluralMapKeys = []*regexp.Regexp{regexp.MustCompile("ch$"), regexp.MustCompile("ss$"), regexp.MustCompile("sh$"), regexp.MustCompile("day$"), regexp.MustCompile("y$"), regexp.MustCompile("x$"), regexp.MustCompile("([^s])s?$")}
var pluralMapValues = []string{"ches", "sses", "shes", "days", "ies", "xes", "${1}s"}
func (scope *Scope) TableName() string {
if scope.Search != nil && len(scope.Search.TableName) > 0 {
return scope.Search.TableName
} else {
if scope.Value == nil {
scope.Err(errors.New("can't get table name"))
return ""
}
data := scope.IndirectValue()
if data.Kind() == reflect.Slice {
elem := data.Type().Elem()
if elem.Kind() == reflect.Ptr {
elem = elem.Elem()
}
data = reflect.New(elem).Elem()
}
if fm := data.MethodByName("TableName"); fm.IsValid() {
if v := fm.Call([]reflect.Value{}); len(v) > 0 {
if result, ok := v[0].Interface().(string); ok {
return result
}
}
}
str := ToSnake(data.Type().Name())
if scope.db == nil || !scope.db.parent.singularTable {
for index, reg := range pluralMapKeys {
if reg.MatchString(str) {
return reg.ReplaceAllString(str, pluralMapValues[index])
}
}
}
return str
}
}
func (scope *Scope) QuotedTableName() string {
if scope.Search != nil && len(scope.Search.TableName) > 0 {
return scope.Search.TableName
} else {
keys := strings.Split(scope.TableName(), ".")
for i, v := range keys {
keys[i] = scope.Quote(v)
}
return strings.Join(keys, ".")
}
}
// CombinedConditionSql get combined condition sql
func (scope *Scope) CombinedConditionSql() string {
return scope.joinsSql() + scope.whereSql() + scope.groupSql() +
scope.havingSql() + scope.orderSql() + scope.limitSql() + scope.offsetSql()
}
func (scope *Scope) FieldByName(name string) (field *Field, ok bool) {
var f reflect.StructField
if scope.Value != nil {
if scope.IndirectValue().Kind() == reflect.Struct {
if f, ok = scope.IndirectValue().Type().FieldByName(SnakeToUpperCamel(name)); ok {
field = scope.fieldFromStruct(f)
}
}
}
return
}
func (scope *Scope) fieldFromStruct(fieldStruct reflect.StructField) *Field {
var field Field
field.Name = fieldStruct.Name
field.DBName = ToSnake(fieldStruct.Name)
value := scope.IndirectValue().FieldByName(fieldStruct.Name)
indirectValue := reflect.Indirect(value)
field.Value = value.Interface()
field.IsBlank = isBlank(value)
// Search for primary key tag identifier
settings := parseTagSetting(fieldStruct.Tag.Get("gorm"))
if scope.PrimaryKey() == field.DBName {
field.IsPrimaryKey = true
}
field.Tag = fieldStruct.Tag
field.SqlTag = scope.sqlTagForField(&field)
if !field.IsIgnored {
// parse association
if !indirectValue.IsValid() {
indirectValue = reflect.New(value.Type())
}
typ := indirectValue.Type()
foreignKey := SnakeToUpperCamel(settings["FOREIGNKEY"])
associationForeignKey := SnakeToUpperCamel(settings["ASSOCIATIONFOREIGNKEY"])
many2many := settings["MANY2MANY"]
scopeTyp := scope.IndirectValue().Type()
switch indirectValue.Kind() {
case reflect.Slice:
typ = typ.Elem()
if typ.Kind() == reflect.Struct {
if foreignKey == "" {
foreignKey = scopeTyp.Name() + "Id"
}
if associationForeignKey == "" {
associationForeignKey = typ.Name() + "Id"
}
// if not many to many, foreign key could be null
if many2many == "" {
if !reflect.New(typ).Elem().FieldByName(foreignKey).IsValid() {
foreignKey = ""
}
}
field.Relationship = &relationship{
JoinTable: many2many,
ForeignKey: foreignKey,
AssociationForeignKey: associationForeignKey,
Kind: "has_many",
}
if many2many != "" {
field.Relationship.Kind = "many_to_many"
}
}
case reflect.Struct:
if !field.IsTime() && !field.IsScanner() {
if foreignKey == "" && scope.HasColumn(field.Name+"Id") {
field.Relationship = &relationship{ForeignKey: field.Name + "Id", Kind: "belongs_to"}
} else if scope.HasColumn(foreignKey) {
field.Relationship = &relationship{ForeignKey: foreignKey, Kind: "belongs_to"}
} else {
if foreignKey == "" {
foreignKey = scopeTyp.Name() + "Id"
}
if reflect.New(typ).Elem().FieldByName(foreignKey).IsValid() {
field.Relationship = &relationship{ForeignKey: foreignKey, Kind: "has_one"}
}
}
}
}
}
return &field
}
// Fields get value's fields
func (scope *Scope) Fields() (fields []*Field) {
if scope.IndirectValue().IsValid() {
scopeTyp := scope.IndirectValue().Type()
for i := 0; i < scopeTyp.NumField(); i++ {
fieldStruct := scopeTyp.Field(i)
if !ast.IsExported(fieldStruct.Name) {
continue
}
fields = append(fields, scope.fieldFromStruct(fieldStruct))
}
}
return
}
// Raw set sql
func (scope *Scope) Raw(sql string) *Scope {
scope.Sql = strings.Replace(sql, "$$", "?", -1)
return scope
}
// Exec invoke sql
func (scope *Scope) Exec() *Scope {
defer scope.Trace(time.Now())
if !scope.HasError() {
result, err := scope.DB().Exec(scope.Sql, scope.SqlVars...)
if scope.Err(err) == nil {
if count, err := result.RowsAffected(); err == nil {
scope.db.RowsAffected = count
}
}
}
return scope
}
// Set set value by name
func (scope *Scope) Set(name string, value interface{}) *Scope {
scope._values[name] = value
return scope
}
// Get get value by name
func (scope *Scope) Get(name string) (value interface{}, ok bool) {
value, ok = scope._values[name]
return
}
// Trace print sql log
func (scope *Scope) Trace(t time.Time) {
if len(scope.Sql) > 0 {
scope.db.slog(scope.Sql, t, scope.SqlVars...)
}
}
// Begin start a transaction
func (scope *Scope) Begin() *Scope {
if db, ok := scope.DB().(sqlDb); ok {
if tx, err := db.Begin(); err == nil {
scope.db.db = interface{}(tx).(sqlCommon)
scope.Set("gorm:started_transaction", true)
}
}
return scope
}
// CommitOrRollback commit current transaction if there is no error, otherwise rollback it
func (scope *Scope) CommitOrRollback() *Scope {
if _, ok := scope.Get("gorm:started_transaction"); ok {
if db, ok := scope.db.db.(sqlTx); ok {
if scope.HasError() {
db.Rollback()
} else {
db.Commit()
}
scope.db.db = scope.db.parent.db
}
}
return scope
}