gtsocial-umbx

model_map_slice.go (2664B)

---

 package bun
 
 import (
 	"context"
 	"database/sql"
 	"errors"
 	"sort"
 
 	"github.com/uptrace/bun/dialect/feature"
 	"github.com/uptrace/bun/schema"
 )
 
 type mapSliceModel struct {
 	mapModel
 	dest *[]map[string]interface{}
 
 	keys []string
 }
 
 var _ Model = (*mapSliceModel)(nil)
 
 func newMapSliceModel(db *DB, dest *[]map[string]interface{}) *mapSliceModel {
 	return &mapSliceModel{
 		mapModel: mapModel{
 			db: db,
 		},
 		dest: dest,
 	}
 }
 
 func (m *mapSliceModel) Value() interface{} {
 	return m.dest
 }
 
 func (m *mapSliceModel) SetCap(cap int) {
 	if cap > 100 {
 		cap = 100
 	}
 	if slice := *m.dest; len(slice) < cap {
 		*m.dest = make([]map[string]interface{}, 0, cap)
 	}
 }
 
 func (m *mapSliceModel) ScanRows(ctx context.Context, rows *sql.Rows) (int, error) {
 	columns, err := rows.Columns()
 	if err != nil {
 		return 0, err
 	}
 
 	m.rows = rows
 	m.columns = columns
 	dest := makeDest(m, len(columns))
 
 	slice := *m.dest
 	if len(slice) > 0 {
 		slice = slice[:0]
 	}
 
 	var n int
 
 	for rows.Next() {
 		m.m = make(map[string]interface{}, len(m.columns))
 
 		m.scanIndex = 0
 		if err := rows.Scan(dest...); err != nil {
 			return 0, err
 		}
 
 		slice = append(slice, m.m)
 		n++
 	}
 	if err := rows.Err(); err != nil {
 		return 0, err
 	}
 
 	*m.dest = slice
 	return n, nil
 }
 
 func (m *mapSliceModel) appendColumns(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if err := m.initKeys(); err != nil {
 		return nil, err
 	}
 
 	for i, k := range m.keys {
 		if i > 0 {
 			b = append(b, ", "...)
 		}
 		b = fmter.AppendIdent(b, k)
 	}
 
 	return b, nil
 }
 
 func (m *mapSliceModel) appendValues(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if err := m.initKeys(); err != nil {
 		return nil, err
 	}
 	slice := *m.dest
 
 	b = append(b, "VALUES "...)
 	if m.db.features.Has(feature.ValuesRow) {
 		b = append(b, "ROW("...)
 	} else {
 		b = append(b, '(')
 	}
 
 	if fmter.IsNop() {
 		for i := range m.keys {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 			b = append(b, '?')
 		}
 		return b, nil
 	}
 
 	for i, el := range slice {
 		if i > 0 {
 			b = append(b, "), "...)
 			if m.db.features.Has(feature.ValuesRow) {
 				b = append(b, "ROW("...)
 			} else {
 				b = append(b, '(')
 			}
 		}
 
 		for j, key := range m.keys {
 			if j > 0 {
 				b = append(b, ", "...)
 			}
 			b = schema.Append(fmter, b, el[key])
 		}
 	}
 
 	b = append(b, ')')
 
 	return b, nil
 }
 
 func (m *mapSliceModel) initKeys() error {
 	if m.keys != nil {
 		return nil
 	}
 
 	slice := *m.dest
 	if len(slice) == 0 {
 		return errors.New("bun: map slice is empty")
 	}
 
 	first := slice[0]
 	keys := make([]string, 0, len(first))
 
 	for k := range first {
 		keys = append(keys, k)
 	}
 
 	sort.Strings(keys)
 	m.keys = keys
 
 	return nil
 }