From 5bf745d7d163f4380e6c2bba8c4afa60534dd087 Mon Sep 17 00:00:00 2001 From: Lunny Xiao Date: Fri, 5 Aug 2016 23:24:16 +0800 Subject: [PATCH] add ToMapString method for rows and row --- db.go | 333 ------------------------------------------------- rows.go | 380 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 380 insertions(+), 333 deletions(-) create mode 100644 rows.go diff --git a/db.go b/db.go index e04bf59b..6111c4b3 100644 --- a/db.go +++ b/db.go @@ -7,7 +7,6 @@ import ( "fmt" "reflect" "regexp" - "sync" ) func MapToSlice(query string, mp interface{}) (string, []interface{}, error) { @@ -103,121 +102,6 @@ func (db *DB) QueryStruct(query string, st interface{}) (*Rows, error) { return db.Query(query, args...) } -type Row struct { - rows *Rows - // One of these two will be non-nil: - err error // deferred error for easy chaining -} - -func (row *Row) Columns() ([]string, error) { - if row.err != nil { - return nil, row.err - } - return row.rows.Columns() -} - -func (row *Row) Scan(dest ...interface{}) error { - if row.err != nil { - return row.err - } - defer row.rows.Close() - - for _, dp := range dest { - if _, ok := dp.(*sql.RawBytes); ok { - return errors.New("sql: RawBytes isn't allowed on Row.Scan") - } - } - - if !row.rows.Next() { - if err := row.rows.Err(); err != nil { - return err - } - return sql.ErrNoRows - } - err := row.rows.Scan(dest...) - if err != nil { - return err - } - // Make sure the query can be processed to completion with no errors. - return row.rows.Close() -} - -func (row *Row) ScanStructByName(dest interface{}) error { - if row.err != nil { - return row.err - } - if !row.rows.Next() { - if err := row.rows.Err(); err != nil { - return err - } - return sql.ErrNoRows - } - err := row.rows.ScanStructByName(dest) - if err != nil { - return err - } - // Make sure the query can be processed to completion with no errors. - return row.rows.Close() -} - -func (row *Row) ScanStructByIndex(dest interface{}) error { - if row.err != nil { - return row.err - } - if !row.rows.Next() { - if err := row.rows.Err(); err != nil { - return err - } - return sql.ErrNoRows - } - err := row.rows.ScanStructByIndex(dest) - if err != nil { - return err - } - // Make sure the query can be processed to completion with no errors. - return row.rows.Close() -} - -// scan data to a slice's pointer, slice's length should equal to columns' number -func (row *Row) ScanSlice(dest interface{}) error { - if row.err != nil { - return row.err - } - if !row.rows.Next() { - if err := row.rows.Err(); err != nil { - return err - } - return sql.ErrNoRows - } - err := row.rows.ScanSlice(dest) - if err != nil { - return err - } - - // Make sure the query can be processed to completion with no errors. - return row.rows.Close() -} - -// scan data to a map's pointer -func (row *Row) ScanMap(dest interface{}) error { - if row.err != nil { - return row.err - } - if !row.rows.Next() { - if err := row.rows.Err(); err != nil { - return err - } - return sql.ErrNoRows - } - err := row.rows.ScanMap(dest) - if err != nil { - return err - } - - // Make sure the query can be processed to completion with no errors. - return row.rows.Close() -} - func (db *DB) QueryRow(query string, args ...interface{}) *Row { rows, err := db.Query(query, args...) if err != nil { @@ -381,44 +265,6 @@ func (db *DB) ExecStruct(query string, st interface{}) (sql.Result, error) { return db.DB.Exec(query, args...) } -type Rows struct { - *sql.Rows - Mapper IMapper -} - -// scan data to a struct's pointer according field index -func (rs *Rows) ScanStructByIndex(dest ...interface{}) error { - if len(dest) == 0 { - return errors.New("at least one struct") - } - - vvvs := make([]reflect.Value, len(dest)) - for i, s := range dest { - vv := reflect.ValueOf(s) - if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Struct { - return errors.New("dest should be a struct's pointer") - } - - vvvs[i] = vv.Elem() - } - - cols, err := rs.Columns() - if err != nil { - return err - } - newDest := make([]interface{}, len(cols)) - - var i = 0 - for _, vvv := range vvvs { - for j := 0; j < vvv.NumField(); j++ { - newDest[i] = vvv.Field(j).Addr().Interface() - i = i + 1 - } - } - - return rs.Rows.Scan(newDest...) -} - type EmptyScanner struct { } @@ -426,185 +272,6 @@ func (EmptyScanner) Scan(src interface{}) error { return nil } -var ( - fieldCache = make(map[reflect.Type]map[string]int) - fieldCacheMutex sync.RWMutex -) - -func fieldByName(v reflect.Value, name string) reflect.Value { - t := v.Type() - fieldCacheMutex.RLock() - cache, ok := fieldCache[t] - fieldCacheMutex.RUnlock() - if !ok { - cache = make(map[string]int) - for i := 0; i < v.NumField(); i++ { - cache[t.Field(i).Name] = i - } - fieldCacheMutex.Lock() - fieldCache[t] = cache - fieldCacheMutex.Unlock() - } - - if i, ok := cache[name]; ok { - return v.Field(i) - } - - return reflect.Zero(t) -} - -// scan data to a struct's pointer according field name -func (rs *Rows) ScanStructByName(dest interface{}) error { - vv := reflect.ValueOf(dest) - if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Struct { - return errors.New("dest should be a struct's pointer") - } - - cols, err := rs.Columns() - if err != nil { - return err - } - - newDest := make([]interface{}, len(cols)) - var v EmptyScanner - for j, name := range cols { - f := fieldByName(vv.Elem(), rs.Mapper.Table2Obj(name)) - if f.IsValid() { - newDest[j] = f.Addr().Interface() - } else { - newDest[j] = &v - } - } - - return rs.Rows.Scan(newDest...) -} - -type cacheStruct struct { - value reflect.Value - idx int -} - -var ( - reflectCache = make(map[reflect.Type]*cacheStruct) - reflectCacheMutex sync.RWMutex -) - -func ReflectNew(typ reflect.Type) reflect.Value { - reflectCacheMutex.RLock() - cs, ok := reflectCache[typ] - reflectCacheMutex.RUnlock() - - const newSize = 200 - - if !ok || cs.idx+1 > newSize-1 { - cs = &cacheStruct{reflect.MakeSlice(reflect.SliceOf(typ), newSize, newSize), 0} - reflectCacheMutex.Lock() - reflectCache[typ] = cs - reflectCacheMutex.Unlock() - } else { - reflectCacheMutex.Lock() - cs.idx = cs.idx + 1 - reflectCacheMutex.Unlock() - } - return cs.value.Index(cs.idx).Addr() -} - -// scan data to a slice's pointer, slice's length should equal to columns' number -func (rs *Rows) ScanSlice(dest interface{}) error { - vv := reflect.ValueOf(dest) - if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Slice { - return errors.New("dest should be a slice's pointer") - } - - vvv := vv.Elem() - cols, err := rs.Columns() - if err != nil { - return err - } - - newDest := make([]interface{}, len(cols)) - - for j := 0; j < len(cols); j++ { - if j >= vvv.Len() { - newDest[j] = reflect.New(vvv.Type().Elem()).Interface() - } else { - newDest[j] = vvv.Index(j).Addr().Interface() - } - } - - err = rs.Rows.Scan(newDest...) - if err != nil { - return err - } - - srcLen := vvv.Len() - for i := srcLen; i < len(cols); i++ { - vvv = reflect.Append(vvv, reflect.ValueOf(newDest[i]).Elem()) - } - return nil -} - -// scan data to a map's pointer -func (rs *Rows) ScanMap(dest interface{}) error { - vv := reflect.ValueOf(dest) - if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Map { - return errors.New("dest should be a map's pointer") - } - - cols, err := rs.Columns() - if err != nil { - return err - } - - newDest := make([]interface{}, len(cols)) - vvv := vv.Elem() - - for i, _ := range cols { - newDest[i] = ReflectNew(vvv.Type().Elem()).Interface() - //v := reflect.New(vvv.Type().Elem()) - //newDest[i] = v.Interface() - } - - err = rs.Rows.Scan(newDest...) - if err != nil { - return err - } - - for i, name := range cols { - vname := reflect.ValueOf(name) - vvv.SetMapIndex(vname, reflect.ValueOf(newDest[i]).Elem()) - } - - return nil -} - -/*func (rs *Rows) ScanMap(dest interface{}) error { - vv := reflect.ValueOf(dest) - if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Map { - return errors.New("dest should be a map's pointer") - } - - cols, err := rs.Columns() - if err != nil { - return err - } - - newDest := make([]interface{}, len(cols)) - err = rs.ScanSlice(newDest) - if err != nil { - return err - } - - vvv := vv.Elem() - - for i, name := range cols { - vname := reflect.ValueOf(name) - vvv.SetMapIndex(vname, reflect.ValueOf(newDest[i]).Elem()) - } - - return nil -}*/ - type Tx struct { *sql.Tx Mapper IMapper diff --git a/rows.go b/rows.go new file mode 100644 index 00000000..c4dec23e --- /dev/null +++ b/rows.go @@ -0,0 +1,380 @@ +package core + +import ( + "database/sql" + "errors" + "reflect" + "sync" +) + +type Rows struct { + *sql.Rows + Mapper IMapper +} + +func (rs *Rows) ToMapString() ([]map[string]string, error) { + cols, err := rs.Columns() + if err != nil { + return nil, err + } + + var results = make([]map[string]string, 0, 10) + for rs.Next() { + var record = make(map[string]string, len(cols)) + err = rs.ScanMap(&record) + if err != nil { + return nil, err + } + results = append(results, record) + } + return results, nil +} + +// scan data to a struct's pointer according field index +func (rs *Rows) ScanStructByIndex(dest ...interface{}) error { + if len(dest) == 0 { + return errors.New("at least one struct") + } + + vvvs := make([]reflect.Value, len(dest)) + for i, s := range dest { + vv := reflect.ValueOf(s) + if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Struct { + return errors.New("dest should be a struct's pointer") + } + + vvvs[i] = vv.Elem() + } + + cols, err := rs.Columns() + if err != nil { + return err + } + newDest := make([]interface{}, len(cols)) + + var i = 0 + for _, vvv := range vvvs { + for j := 0; j < vvv.NumField(); j++ { + newDest[i] = vvv.Field(j).Addr().Interface() + i = i + 1 + } + } + + return rs.Rows.Scan(newDest...) +} + +var ( + fieldCache = make(map[reflect.Type]map[string]int) + fieldCacheMutex sync.RWMutex +) + +func fieldByName(v reflect.Value, name string) reflect.Value { + t := v.Type() + fieldCacheMutex.RLock() + cache, ok := fieldCache[t] + fieldCacheMutex.RUnlock() + if !ok { + cache = make(map[string]int) + for i := 0; i < v.NumField(); i++ { + cache[t.Field(i).Name] = i + } + fieldCacheMutex.Lock() + fieldCache[t] = cache + fieldCacheMutex.Unlock() + } + + if i, ok := cache[name]; ok { + return v.Field(i) + } + + return reflect.Zero(t) +} + +// scan data to a struct's pointer according field name +func (rs *Rows) ScanStructByName(dest interface{}) error { + vv := reflect.ValueOf(dest) + if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Struct { + return errors.New("dest should be a struct's pointer") + } + + cols, err := rs.Columns() + if err != nil { + return err + } + + newDest := make([]interface{}, len(cols)) + var v EmptyScanner + for j, name := range cols { + f := fieldByName(vv.Elem(), rs.Mapper.Table2Obj(name)) + if f.IsValid() { + newDest[j] = f.Addr().Interface() + } else { + newDest[j] = &v + } + } + + return rs.Rows.Scan(newDest...) +} + +type cacheStruct struct { + value reflect.Value + idx int +} + +var ( + reflectCache = make(map[reflect.Type]*cacheStruct) + reflectCacheMutex sync.RWMutex +) + +func ReflectNew(typ reflect.Type) reflect.Value { + reflectCacheMutex.RLock() + cs, ok := reflectCache[typ] + reflectCacheMutex.RUnlock() + + const newSize = 200 + + if !ok || cs.idx+1 > newSize-1 { + cs = &cacheStruct{reflect.MakeSlice(reflect.SliceOf(typ), newSize, newSize), 0} + reflectCacheMutex.Lock() + reflectCache[typ] = cs + reflectCacheMutex.Unlock() + } else { + reflectCacheMutex.Lock() + cs.idx = cs.idx + 1 + reflectCacheMutex.Unlock() + } + return cs.value.Index(cs.idx).Addr() +} + +// scan data to a slice's pointer, slice's length should equal to columns' number +func (rs *Rows) ScanSlice(dest interface{}) error { + vv := reflect.ValueOf(dest) + if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Slice { + return errors.New("dest should be a slice's pointer") + } + + vvv := vv.Elem() + cols, err := rs.Columns() + if err != nil { + return err + } + + newDest := make([]interface{}, len(cols)) + + for j := 0; j < len(cols); j++ { + if j >= vvv.Len() { + newDest[j] = reflect.New(vvv.Type().Elem()).Interface() + } else { + newDest[j] = vvv.Index(j).Addr().Interface() + } + } + + err = rs.Rows.Scan(newDest...) + if err != nil { + return err + } + + srcLen := vvv.Len() + for i := srcLen; i < len(cols); i++ { + vvv = reflect.Append(vvv, reflect.ValueOf(newDest[i]).Elem()) + } + return nil +} + +// scan data to a map's pointer +func (rs *Rows) ScanMap(dest interface{}) error { + vv := reflect.ValueOf(dest) + if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Map { + return errors.New("dest should be a map's pointer") + } + + cols, err := rs.Columns() + if err != nil { + return err + } + + newDest := make([]interface{}, len(cols)) + vvv := vv.Elem() + + for i, _ := range cols { + newDest[i] = ReflectNew(vvv.Type().Elem()).Interface() + //v := reflect.New(vvv.Type().Elem()) + //newDest[i] = v.Interface() + } + + err = rs.Rows.Scan(newDest...) + if err != nil { + return err + } + + for i, name := range cols { + vname := reflect.ValueOf(name) + vvv.SetMapIndex(vname, reflect.ValueOf(newDest[i]).Elem()) + } + + return nil +} + +/*func (rs *Rows) ScanMap(dest interface{}) error { + vv := reflect.ValueOf(dest) + if vv.Kind() != reflect.Ptr || vv.Elem().Kind() != reflect.Map { + return errors.New("dest should be a map's pointer") + } + + cols, err := rs.Columns() + if err != nil { + return err + } + + newDest := make([]interface{}, len(cols)) + err = rs.ScanSlice(newDest) + if err != nil { + return err + } + + vvv := vv.Elem() + + for i, name := range cols { + vname := reflect.ValueOf(name) + vvv.SetMapIndex(vname, reflect.ValueOf(newDest[i]).Elem()) + } + + return nil +}*/ +type Row struct { + rows *Rows + // One of these two will be non-nil: + err error // deferred error for easy chaining +} + +func (row *Row) Columns() ([]string, error) { + if row.err != nil { + return nil, row.err + } + return row.rows.Columns() +} + +func (row *Row) Scan(dest ...interface{}) error { + if row.err != nil { + return row.err + } + defer row.rows.Close() + + for _, dp := range dest { + if _, ok := dp.(*sql.RawBytes); ok { + return errors.New("sql: RawBytes isn't allowed on Row.Scan") + } + } + + if !row.rows.Next() { + if err := row.rows.Err(); err != nil { + return err + } + return sql.ErrNoRows + } + err := row.rows.Scan(dest...) + if err != nil { + return err + } + // Make sure the query can be processed to completion with no errors. + return row.rows.Close() +} + +func (row *Row) ScanStructByName(dest interface{}) error { + if row.err != nil { + return row.err + } + defer row.rows.Close() + + if !row.rows.Next() { + if err := row.rows.Err(); err != nil { + return err + } + return sql.ErrNoRows + } + err := row.rows.ScanStructByName(dest) + if err != nil { + return err + } + // Make sure the query can be processed to completion with no errors. + return row.rows.Close() +} + +func (row *Row) ScanStructByIndex(dest interface{}) error { + if row.err != nil { + return row.err + } + defer row.rows.Close() + + if !row.rows.Next() { + if err := row.rows.Err(); err != nil { + return err + } + return sql.ErrNoRows + } + err := row.rows.ScanStructByIndex(dest) + if err != nil { + return err + } + // Make sure the query can be processed to completion with no errors. + return row.rows.Close() +} + +// scan data to a slice's pointer, slice's length should equal to columns' number +func (row *Row) ScanSlice(dest interface{}) error { + if row.err != nil { + return row.err + } + defer row.rows.Close() + + if !row.rows.Next() { + if err := row.rows.Err(); err != nil { + return err + } + return sql.ErrNoRows + } + err := row.rows.ScanSlice(dest) + if err != nil { + return err + } + + // Make sure the query can be processed to completion with no errors. + return row.rows.Close() +} + +// scan data to a map's pointer +func (row *Row) ScanMap(dest interface{}) error { + if row.err != nil { + return row.err + } + defer row.rows.Close() + + if !row.rows.Next() { + if err := row.rows.Err(); err != nil { + return err + } + return sql.ErrNoRows + } + err := row.rows.ScanMap(dest) + if err != nil { + return err + } + + // Make sure the query can be processed to completion with no errors. + return row.rows.Close() +} + +func (row *Row) ToMapString() (map[string]string, error) { + cols, err := row.Columns() + if err != nil { + return nil, err + } + + var record = make(map[string]string, len(cols)) + err = row.ScanMap(&record) + if err != nil { + return nil, err + } + + return record, nil +}