package gorm import ( "database/sql" "errors" "fmt" "reflect" "strings" "time" ) // DB contains information for current db connection type DB struct { Value interface{} Error error RowsAffected int64 // single db db SQLCommon blockGlobalUpdate bool logMode int logger logger search *search values map[string]interface{} // global db parent *DB callbacks *Callback dialect Dialect singularTable bool } // Open initialize a new db connection, need to import driver first, e.g: // // import _ "github.com/go-sql-driver/mysql" // func main() { // db, err := gorm.Open("mysql", "user:password@/dbname?charset=utf8&parseTime=True&loc=Local") // } // GORM has wrapped some drivers, for easier to remember driver's import path, so you could import the mysql driver with // import _ "github.com/jinzhu/gorm/dialects/mysql" // // import _ "github.com/jinzhu/gorm/dialects/postgres" // // import _ "github.com/jinzhu/gorm/dialects/sqlite" // // import _ "github.com/jinzhu/gorm/dialects/mssql" func Open(dialect string, args ...interface{}) (db *DB, err error) { if len(args) == 0 { err = errors.New("invalid database source") return nil, err } var source string var dbSQL SQLCommon switch value := args[0].(type) { case string: var driver = dialect if len(args) == 1 { source = value } else if len(args) >= 2 { driver = value source = args[1].(string) } dbSQL, err = sql.Open(driver, source) case SQLCommon: dbSQL = value } db = &DB{ db: dbSQL, logger: defaultLogger, values: map[string]interface{}{}, callbacks: DefaultCallback, dialect: newDialect(dialect, dbSQL), } db.parent = db if err != nil { return } // Send a ping to make sure the database connection is alive. if d, ok := dbSQL.(*sql.DB); ok { if err = d.Ping(); err != nil { d.Close() } } return } // New clone a new db connection without search conditions func (s *DB) New() *DB { clone := s.clone() clone.search = nil clone.Value = nil return clone } type closer interface { Close() error } // Close close current db connection. If database connection is not an io.Closer, returns an error. func (s *DB) Close() error { if db, ok := s.parent.db.(closer); ok { return db.Close() } return errors.New("can't close current db") } // DB get `*sql.DB` from current connection // If the underlying database connection is not a *sql.DB, returns nil func (s *DB) DB() *sql.DB { db, _ := s.db.(*sql.DB) return db } // CommonDB return the underlying `*sql.DB` or `*sql.Tx` instance, mainly intended to allow coexistence with legacy non-GORM code. func (s *DB) CommonDB() SQLCommon { return s.db } // Dialect get dialect func (s *DB) Dialect() Dialect { return s.parent.dialect } // Callback return `Callbacks` container, you could add/change/delete callbacks with it // db.Callback().Create().Register("update_created_at", updateCreated) // Refer https://jinzhu.github.io/gorm/development.html#callbacks func (s *DB) Callback() *Callback { s.parent.callbacks = s.parent.callbacks.clone() return s.parent.callbacks } // SetLogger replace default logger func (s *DB) SetLogger(log logger) { s.logger = log } // LogMode set log mode, `true` for detailed logs, `false` for no log, default, will only print error logs func (s *DB) LogMode(enable bool) *DB { if enable { s.logMode = 2 } else { s.logMode = 1 } return s } // BlockGlobalUpdate if true, generates an error on update/delete without where clause. // This is to prevent eventual error with empty objects updates/deletions func (s *DB) BlockGlobalUpdate(enable bool) *DB { s.blockGlobalUpdate = enable return s } // HasBlockGlobalUpdate return state of block func (s *DB) HasBlockGlobalUpdate() bool { return s.blockGlobalUpdate } // SingularTable use singular table by default func (s *DB) SingularTable(enable bool) { modelStructsMap = newModelStructsMap() s.parent.singularTable = enable } // NewScope create a scope for current operation func (s *DB) NewScope(value interface{}) *Scope { dbClone := s.clone() dbClone.Value = value return &Scope{db: dbClone, Search: dbClone.search.clone(), Value: value} } // QueryExpr returns the query as expr object func (s *DB) QueryExpr() *expr { scope := s.NewScope(s.Value) scope.InstanceSet("skip_bindvar", true) scope.prepareQuerySQL() return Expr(scope.SQL, scope.SQLVars...) } // SubQuery returns the query as sub query func (s *DB) SubQuery() *expr { scope := s.NewScope(s.Value) scope.InstanceSet("skip_bindvar", true) scope.prepareQuerySQL() return Expr(fmt.Sprintf("(%v)", scope.SQL), scope.SQLVars...) } // Where return a new relation, filter records with given conditions, accepts `map`, `struct` or `string` as conditions, refer http://jinzhu.github.io/gorm/crud.html#query func (s *DB) Where(query interface{}, args ...interface{}) *DB { return s.clone().search.Where(query, args...).db } // Or filter records that match before conditions or this one, similar to `Where` func (s *DB) Or(query interface{}, args ...interface{}) *DB { return s.clone().search.Or(query, args...).db } // Not filter records that don't match current conditions, similar to `Where` func (s *DB) Not(query interface{}, args ...interface{}) *DB { return s.clone().search.Not(query, args...).db } // Limit specify the number of records to be retrieved func (s *DB) Limit(limit interface{}) *DB { return s.clone().search.Limit(limit).db } // Offset specify the number of records to skip before starting to return the records func (s *DB) Offset(offset interface{}) *DB { return s.clone().search.Offset(offset).db } // Order specify order when retrieve records from database, set reorder to `true` to overwrite defined conditions // db.Order("name DESC") // db.Order("name DESC", true) // reorder // db.Order(gorm.Expr("name = ? DESC", "first")) // sql expression func (s *DB) Order(value interface{}, reorder ...bool) *DB { return s.clone().search.Order(value, reorder...).db } // Select specify fields that you want to retrieve from database when querying, by default, will select all fields; // When creating/updating, specify fields that you want to save to database func (s *DB) Select(query interface{}, args ...interface{}) *DB { return s.clone().search.Select(query, args...).db } // Omit specify fields that you want to ignore when saving to database for creating, updating func (s *DB) Omit(columns ...string) *DB { return s.clone().search.Omit(columns...).db } // Group specify the group method on the find func (s *DB) Group(query string) *DB { return s.clone().search.Group(query).db } // Having specify HAVING conditions for GROUP BY func (s *DB) Having(query interface{}, values ...interface{}) *DB { return s.clone().search.Having(query, values...).db } // Joins specify Joins conditions // db.Joins("JOIN emails ON emails.user_id = users.id AND emails.email = ?", "jinzhu@example.org").Find(&user) func (s *DB) Joins(query string, args ...interface{}) *DB { return s.clone().search.Joins(query, args...).db } // Scopes pass current database connection to arguments `func(*DB) *DB`, which could be used to add conditions dynamically // func AmountGreaterThan1000(db *gorm.DB) *gorm.DB { // return db.Where("amount > ?", 1000) // } // // func OrderStatus(status []string) func (db *gorm.DB) *gorm.DB { // return func (db *gorm.DB) *gorm.DB { // return db.Scopes(AmountGreaterThan1000).Where("status in (?)", status) // } // } // // db.Scopes(AmountGreaterThan1000, OrderStatus([]string{"paid", "shipped"})).Find(&orders) // Refer https://jinzhu.github.io/gorm/crud.html#scopes func (s *DB) Scopes(funcs ...func(*DB) *DB) *DB { for _, f := range funcs { s = f(s) } return s } // Unscoped return all record including deleted record, refer Soft Delete https://jinzhu.github.io/gorm/crud.html#soft-delete func (s *DB) Unscoped() *DB { return s.clone().search.unscoped().db } // Attrs initialize struct with argument if record not found with `FirstOrInit` https://jinzhu.github.io/gorm/crud.html#firstorinit or `FirstOrCreate` https://jinzhu.github.io/gorm/crud.html#firstorcreate func (s *DB) Attrs(attrs ...interface{}) *DB { return s.clone().search.Attrs(attrs...).db } // Assign assign result with argument regardless it is found or not with `FirstOrInit` https://jinzhu.github.io/gorm/crud.html#firstorinit or `FirstOrCreate` https://jinzhu.github.io/gorm/crud.html#firstorcreate func (s *DB) Assign(attrs ...interface{}) *DB { return s.clone().search.Assign(attrs...).db } // First find first record that match given conditions, order by primary key func (s *DB) First(out interface{}, where ...interface{}) *DB { newScope := s.NewScope(out) newScope.Search.Limit(1) return newScope.Set("gorm:order_by_primary_key", "ASC"). inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db } // Take return a record that match given conditions, the order will depend on the database implementation func (s *DB) Take(out interface{}, where ...interface{}) *DB { newScope := s.NewScope(out) newScope.Search.Limit(1) return newScope.inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db } // Last find last record that match given conditions, order by primary key func (s *DB) Last(out interface{}, where ...interface{}) *DB { newScope := s.NewScope(out) newScope.Search.Limit(1) return newScope.Set("gorm:order_by_primary_key", "DESC"). inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db } // Find find records that match given conditions func (s *DB) Find(out interface{}, where ...interface{}) *DB { return s.NewScope(out).inlineCondition(where...).callCallbacks(s.parent.callbacks.queries).db } // Scan scan value to a struct func (s *DB) Scan(dest interface{}) *DB { return s.NewScope(s.Value).Set("gorm:query_destination", dest).callCallbacks(s.parent.callbacks.queries).db } // Row return `*sql.Row` with given conditions func (s *DB) Row() *sql.Row { return s.NewScope(s.Value).row() } // Rows return `*sql.Rows` with given conditions func (s *DB) Rows() (*sql.Rows, error) { return s.NewScope(s.Value).rows() } // ScanRows scan `*sql.Rows` to give struct func (s *DB) ScanRows(rows *sql.Rows, result interface{}) error { var ( scope = s.NewScope(result) clone = scope.db columns, err = rows.Columns() ) if clone.AddError(err) == nil { scope.scan(rows, columns, scope.Fields()) } return clone.Error } // Pluck used to query single column from a model as a map // var ages []int64 // db.Find(&users).Pluck("age", &ages) func (s *DB) Pluck(column string, value interface{}) *DB { return s.NewScope(s.Value).pluck(column, value).db } // Count get how many records for a model func (s *DB) Count(value interface{}) *DB { return s.NewScope(s.Value).count(value).db } // Related get related associations func (s *DB) Related(value interface{}, foreignKeys ...string) *DB { return s.NewScope(s.Value).related(value, foreignKeys...).db } // FirstOrInit find first matched record or initialize a new one with given conditions (only works with struct, map conditions) // https://jinzhu.github.io/gorm/crud.html#firstorinit func (s *DB) FirstOrInit(out interface{}, where ...interface{}) *DB { c := s.clone() if result := c.First(out, where...); result.Error != nil { if !result.RecordNotFound() { return result } c.NewScope(out).inlineCondition(where...).initialize() } else { c.NewScope(out).updatedAttrsWithValues(c.search.assignAttrs) } return c } // FirstOrCreate find first matched record or create a new one with given conditions (only works with struct, map conditions) // https://jinzhu.github.io/gorm/crud.html#firstorcreate func (s *DB) FirstOrCreate(out interface{}, where ...interface{}) *DB { c := s.clone() if result := s.First(out, where...); result.Error != nil { if !result.RecordNotFound() { return result } return c.NewScope(out).inlineCondition(where...).initialize().callCallbacks(c.parent.callbacks.creates).db } else if len(c.search.assignAttrs) > 0 { return c.NewScope(out).InstanceSet("gorm:update_interface", c.search.assignAttrs).callCallbacks(c.parent.callbacks.updates).db } return c } // Update update attributes with callbacks, refer: https://jinzhu.github.io/gorm/crud.html#update func (s *DB) Update(attrs ...interface{}) *DB { return s.Updates(toSearchableMap(attrs...), true) } // Updates update attributes with callbacks, refer: https://jinzhu.github.io/gorm/crud.html#update func (s *DB) Updates(values interface{}, ignoreProtectedAttrs ...bool) *DB { return s.NewScope(s.Value). Set("gorm:ignore_protected_attrs", len(ignoreProtectedAttrs) > 0). InstanceSet("gorm:update_interface", values). callCallbacks(s.parent.callbacks.updates).db } // UpdateColumn update attributes without callbacks, refer: https://jinzhu.github.io/gorm/crud.html#update func (s *DB) UpdateColumn(attrs ...interface{}) *DB { return s.UpdateColumns(toSearchableMap(attrs...)) } // UpdateColumns update attributes without callbacks, refer: https://jinzhu.github.io/gorm/crud.html#update func (s *DB) UpdateColumns(values interface{}) *DB { return s.NewScope(s.Value). Set("gorm:update_column", true). Set("gorm:save_associations", false). InstanceSet("gorm:update_interface", values). callCallbacks(s.parent.callbacks.updates).db } // Save update value in database, if the value doesn't have primary key, will insert it func (s *DB) Save(value interface{}) *DB { scope := s.NewScope(value) if !scope.PrimaryKeyZero() { newDB := scope.callCallbacks(s.parent.callbacks.updates).db if newDB.Error == nil && newDB.RowsAffected == 0 { return s.New().FirstOrCreate(value) } return newDB } return scope.callCallbacks(s.parent.callbacks.creates).db } // Create insert the value into database func (s *DB) Create(value interface{}) *DB { scope := s.NewScope(value) return scope.callCallbacks(s.parent.callbacks.creates).db } // Delete delete value match given conditions, if the value has primary key, then will including the primary key as condition func (s *DB) Delete(value interface{}, where ...interface{}) *DB { return s.NewScope(value).inlineCondition(where...).callCallbacks(s.parent.callbacks.deletes).db } // Raw use raw sql as conditions, won't run it unless invoked by other methods // db.Raw("SELECT name, age FROM users WHERE name = ?", 3).Scan(&result) func (s *DB) Raw(sql string, values ...interface{}) *DB { return s.clone().search.Raw(true).Where(sql, values...).db } // Exec execute raw sql func (s *DB) Exec(sql string, values ...interface{}) *DB { scope := s.NewScope(nil) generatedSQL := scope.buildCondition(map[string]interface{}{"query": sql, "args": values}, true) generatedSQL = strings.TrimSuffix(strings.TrimPrefix(generatedSQL, "("), ")") scope.Raw(generatedSQL) return scope.Exec().db } // Model specify the model you would like to run db operations // // update all users's name to `hello` // db.Model(&User{}).Update("name", "hello") // // if user's primary key is non-blank, will use it as condition, then will only update the user's name to `hello` // db.Model(&user).Update("name", "hello") func (s *DB) Model(value interface{}) *DB { c := s.clone() c.Value = value return c } // Table specify the table you would like to run db operations func (s *DB) Table(name string) *DB { clone := s.clone() clone.search.Table(name) clone.Value = nil return clone } // Debug start debug mode func (s *DB) Debug() *DB { return s.clone().LogMode(true) } // Begin begin a transaction func (s *DB) Begin() *DB { c := s.clone() if db, ok := c.db.(sqlDb); ok && db != nil { tx, err := db.Begin() c.db = interface{}(tx).(SQLCommon) c.AddError(err) } else { c.AddError(ErrCantStartTransaction) } return c } // Commit commit a transaction func (s *DB) Commit() *DB { if db, ok := s.db.(sqlTx); ok && db != nil { s.AddError(db.Commit()) } else { s.AddError(ErrInvalidTransaction) } return s } // Rollback rollback a transaction func (s *DB) Rollback() *DB { if db, ok := s.db.(sqlTx); ok && db != nil { s.AddError(db.Rollback()) } else { s.AddError(ErrInvalidTransaction) } return s } // NewRecord check if value's primary key is blank func (s *DB) NewRecord(value interface{}) bool { return s.NewScope(value).PrimaryKeyZero() } // RecordNotFound check if returning ErrRecordNotFound error func (s *DB) RecordNotFound() bool { for _, err := range s.GetErrors() { if err == ErrRecordNotFound { return true } } return false } // CreateTable create table for models func (s *DB) CreateTable(models ...interface{}) *DB { db := s.Unscoped() for _, model := range models { db = db.NewScope(model).createTable().db } return db } // DropTable drop table for models func (s *DB) DropTable(values ...interface{}) *DB { db := s.clone() for _, value := range values { if tableName, ok := value.(string); ok { db = db.Table(tableName) } db = db.NewScope(value).dropTable().db } return db } // DropTableIfExists drop table if it is exist func (s *DB) DropTableIfExists(values ...interface{}) *DB { db := s.clone() for _, value := range values { if s.HasTable(value) { db.AddError(s.DropTable(value).Error) } } return db } // HasTable check has table or not func (s *DB) HasTable(value interface{}) bool { var ( scope = s.NewScope(value) tableName string ) if name, ok := value.(string); ok { tableName = name } else { tableName = scope.TableName() } has := scope.Dialect().HasTable(tableName) s.AddError(scope.db.Error) return has } // AutoMigrate run auto migration for given models, will only add missing fields, won't delete/change current data func (s *DB) AutoMigrate(values ...interface{}) *DB { db := s.Unscoped() for _, value := range values { db = db.NewScope(value).autoMigrate().db } return db } // ModifyColumn modify column to type func (s *DB) ModifyColumn(column string, typ string) *DB { scope := s.NewScope(s.Value) scope.modifyColumn(column, typ) return scope.db } // DropColumn drop a column func (s *DB) DropColumn(column string) *DB { scope := s.NewScope(s.Value) scope.dropColumn(column) return scope.db } // AddIndex add index for columns with given name func (s *DB) AddIndex(indexName string, columns ...string) *DB { scope := s.Unscoped().NewScope(s.Value) scope.addIndex(false, indexName, columns...) return scope.db } // AddUniqueIndex add unique index for columns with given name func (s *DB) AddUniqueIndex(indexName string, columns ...string) *DB { scope := s.Unscoped().NewScope(s.Value) scope.addIndex(true, indexName, columns...) return scope.db } // RemoveIndex remove index with name func (s *DB) RemoveIndex(indexName string) *DB { scope := s.NewScope(s.Value) scope.removeIndex(indexName) return scope.db } // AddForeignKey Add foreign key to the given scope, e.g: // db.Model(&User{}).AddForeignKey("city_id", "cities(id)", "RESTRICT", "RESTRICT") func (s *DB) AddForeignKey(field string, dest string, onDelete string, onUpdate string) *DB { scope := s.NewScope(s.Value) scope.addForeignKey(field, dest, onDelete, onUpdate) return scope.db } // RemoveForeignKey Remove foreign key from the given scope, e.g: // db.Model(&User{}).RemoveForeignKey("city_id", "cities(id)") func (s *DB) RemoveForeignKey(field string, dest string) *DB { scope := s.clone().NewScope(s.Value) scope.removeForeignKey(field, dest) return scope.db } // Association start `Association Mode` to handler relations things easir in that mode, refer: https://jinzhu.github.io/gorm/associations.html#association-mode func (s *DB) Association(column string) *Association { var err error var scope = s.Set("gorm:association:source", s.Value).NewScope(s.Value) if primaryField := scope.PrimaryField(); primaryField.IsBlank { err = errors.New("primary key can't be nil") } else { if field, ok := scope.FieldByName(column); ok { if field.Relationship == nil || len(field.Relationship.ForeignFieldNames) == 0 { err = fmt.Errorf("invalid association %v for %v", column, scope.IndirectValue().Type()) } else { return &Association{scope: scope, column: column, field: field} } } else { err = fmt.Errorf("%v doesn't have column %v", scope.IndirectValue().Type(), column) } } return &Association{Error: err} } // Preload preload associations with given conditions // db.Preload("Orders", "state NOT IN (?)", "cancelled").Find(&users) func (s *DB) Preload(column string, conditions ...interface{}) *DB { return s.clone().search.Preload(column, conditions...).db } // Set set setting by name, which could be used in callbacks, will clone a new db, and update its setting func (s *DB) Set(name string, value interface{}) *DB { return s.clone().InstantSet(name, value) } // InstantSet instant set setting, will affect current db func (s *DB) InstantSet(name string, value interface{}) *DB { s.values[name] = value return s } // Get get setting by name func (s *DB) Get(name string) (value interface{}, ok bool) { value, ok = s.values[name] return } // SetJoinTableHandler set a model's join table handler for a relation func (s *DB) SetJoinTableHandler(source interface{}, column string, handler JoinTableHandlerInterface) { scope := s.NewScope(source) for _, field := range scope.GetModelStruct().StructFields { if field.Name == column || field.DBName == column { if many2many := field.TagSettings["MANY2MANY"]; many2many != "" { source := (&Scope{Value: source}).GetModelStruct().ModelType destination := (&Scope{Value: reflect.New(field.Struct.Type).Interface()}).GetModelStruct().ModelType handler.Setup(field.Relationship, many2many, source, destination) field.Relationship.JoinTableHandler = handler if table := handler.Table(s); scope.Dialect().HasTable(table) { s.Table(table).AutoMigrate(handler) } } } } } // AddError add error to the db func (s *DB) AddError(err error) error { if err != nil { if err != ErrRecordNotFound { if s.logMode == 0 { go s.print(fileWithLineNum(), err) } else { s.log(err) } errors := Errors(s.GetErrors()) errors = errors.Add(err) if len(errors) > 1 { err = errors } } s.Error = err } return err } // GetErrors get happened errors from the db func (s *DB) GetErrors() []error { if errs, ok := s.Error.(Errors); ok { return errs } else if s.Error != nil { return []error{s.Error} } return []error{} } //////////////////////////////////////////////////////////////////////////////// // Private Methods For DB //////////////////////////////////////////////////////////////////////////////// func (s *DB) clone() *DB { db := &DB{ db: s.db, parent: s.parent, logger: s.logger, logMode: s.logMode, values: map[string]interface{}{}, Value: s.Value, Error: s.Error, blockGlobalUpdate: s.blockGlobalUpdate, } for key, value := range s.values { db.values[key] = value } if s.search == nil { db.search = &search{limit: -1, offset: -1} } else { db.search = s.search.clone() } db.search.db = db return db } func (s *DB) print(v ...interface{}) { s.logger.Print(v...) } func (s *DB) log(v ...interface{}) { if s != nil && s.logMode == 2 { s.print(append([]interface{}{"log", fileWithLineNum()}, v...)...) } } func (s *DB) slog(sql string, t time.Time, vars ...interface{}) { if s.logMode == 2 { s.print("sql", fileWithLineNum(), NowFunc().Sub(t), sql, vars, s.RowsAffected) } }