gotosocial/vendor/github.com/uptrace/bun/model_table_struct.go
tobi 2dc9fc1626
Pg to bun (#148)
* start moving to bun

* changing more stuff

* more

* and yet more

* tests passing

* seems stable now

* more big changes

* small fix

* little fixes
2021-08-25 15:34:33 +02:00

346 lines
7 KiB
Go

package bun
import (
"context"
"database/sql"
"fmt"
"reflect"
"strings"
"github.com/uptrace/bun/dialect"
"github.com/uptrace/bun/schema"
)
type structTableModel struct {
db *DB
table *schema.Table
rel *schema.Relation
joins []join
dest interface{}
root reflect.Value
index []int
strct reflect.Value
structInited bool
structInitErr error
columns []string
scanIndex int
}
var _ tableModel = (*structTableModel)(nil)
func newStructTableModel(db *DB, dest interface{}, table *schema.Table) *structTableModel {
return &structTableModel{
db: db,
table: table,
dest: dest,
}
}
func newStructTableModelValue(db *DB, dest interface{}, v reflect.Value) *structTableModel {
return &structTableModel{
db: db,
table: db.Table(v.Type()),
dest: dest,
root: v,
strct: v,
}
}
func (m *structTableModel) Value() interface{} {
return m.dest
}
func (m *structTableModel) Table() *schema.Table {
return m.table
}
func (m *structTableModel) Relation() *schema.Relation {
return m.rel
}
func (m *structTableModel) Root() reflect.Value {
return m.root
}
func (m *structTableModel) Index() []int {
return m.index
}
func (m *structTableModel) ParentIndex() []int {
return m.index[:len(m.index)-len(m.rel.Field.Index)]
}
func (m *structTableModel) Mount(host reflect.Value) {
m.strct = host.FieldByIndex(m.rel.Field.Index)
m.structInited = false
}
func (m *structTableModel) initStruct() error {
if m.structInited {
return m.structInitErr
}
m.structInited = true
switch m.strct.Kind() {
case reflect.Invalid:
m.structInitErr = errNilModel
return m.structInitErr
case reflect.Interface:
m.strct = m.strct.Elem()
}
if m.strct.Kind() == reflect.Ptr {
if m.strct.IsNil() {
m.strct.Set(reflect.New(m.strct.Type().Elem()))
m.strct = m.strct.Elem()
} else {
m.strct = m.strct.Elem()
}
}
m.mountJoins()
return nil
}
func (m *structTableModel) mountJoins() {
for i := range m.joins {
j := &m.joins[i]
switch j.Relation.Type {
case schema.HasOneRelation, schema.BelongsToRelation:
j.JoinModel.Mount(m.strct)
}
}
}
var _ schema.BeforeScanHook = (*structTableModel)(nil)
func (m *structTableModel) BeforeScan(ctx context.Context) error {
if !m.table.HasBeforeScanHook() {
return nil
}
return callBeforeScanHook(ctx, m.strct.Addr())
}
var _ schema.AfterScanHook = (*structTableModel)(nil)
func (m *structTableModel) AfterScan(ctx context.Context) error {
if !m.table.HasAfterScanHook() || !m.structInited {
return nil
}
var firstErr error
if err := callAfterScanHook(ctx, m.strct.Addr()); err != nil && firstErr == nil {
firstErr = err
}
for _, j := range m.joins {
switch j.Relation.Type {
case schema.HasOneRelation, schema.BelongsToRelation:
if err := j.JoinModel.AfterScan(ctx); err != nil && firstErr == nil {
firstErr = err
}
}
}
return firstErr
}
func (m *structTableModel) GetJoin(name string) *join {
for i := range m.joins {
j := &m.joins[i]
if j.Relation.Field.Name == name || j.Relation.Field.GoName == name {
return j
}
}
return nil
}
func (m *structTableModel) GetJoins() []join {
return m.joins
}
func (m *structTableModel) AddJoin(j join) *join {
m.joins = append(m.joins, j)
return &m.joins[len(m.joins)-1]
}
func (m *structTableModel) Join(name string, apply func(*SelectQuery) *SelectQuery) *join {
return m.join(m.strct, name, apply)
}
func (m *structTableModel) join(
bind reflect.Value, name string, apply func(*SelectQuery) *SelectQuery,
) *join {
path := strings.Split(name, ".")
index := make([]int, 0, len(path))
currJoin := join{
BaseModel: m,
JoinModel: m,
}
var lastJoin *join
for _, name := range path {
relation, ok := currJoin.JoinModel.Table().Relations[name]
if !ok {
return nil
}
currJoin.Relation = relation
index = append(index, relation.Field.Index...)
if j := currJoin.JoinModel.GetJoin(name); j != nil {
currJoin.BaseModel = j.BaseModel
currJoin.JoinModel = j.JoinModel
lastJoin = j
} else {
model, err := newTableModelIndex(m.db, m.table, bind, index, relation)
if err != nil {
return nil
}
currJoin.Parent = lastJoin
currJoin.BaseModel = currJoin.JoinModel
currJoin.JoinModel = model
lastJoin = currJoin.BaseModel.AddJoin(currJoin)
}
}
// No joins with such name.
if lastJoin == nil {
return nil
}
if apply != nil {
lastJoin.ApplyQueryFunc = apply
}
return lastJoin
}
func (m *structTableModel) updateSoftDeleteField() error {
fv := m.table.SoftDeleteField.Value(m.strct)
return m.table.UpdateSoftDeleteField(fv)
}
func (m *structTableModel) ScanRows(ctx context.Context, rows *sql.Rows) (int, error) {
if !rows.Next() {
return 0, rows.Err()
}
if err := m.ScanRow(ctx, rows); err != nil {
return 0, err
}
// For inserts, SQLite3 can return a row like it was inserted sucessfully and then
// an actual error for the next row. See issues/100.
if m.db.dialect.Name() == dialect.SQLite {
_ = rows.Next()
if err := rows.Err(); err != nil {
return 0, err
}
}
return 1, nil
}
func (m *structTableModel) ScanRow(ctx context.Context, rows *sql.Rows) error {
columns, err := rows.Columns()
if err != nil {
return err
}
m.columns = columns
dest := makeDest(m, len(columns))
return m.scanRow(ctx, rows, dest)
}
func (m *structTableModel) scanRow(ctx context.Context, rows *sql.Rows, dest []interface{}) error {
if err := m.BeforeScan(ctx); err != nil {
return err
}
m.scanIndex = 0
if err := rows.Scan(dest...); err != nil {
return err
}
if err := m.AfterScan(ctx); err != nil {
return err
}
return nil
}
func (m *structTableModel) Scan(src interface{}) error {
column := m.columns[m.scanIndex]
m.scanIndex++
return m.ScanColumn(unquote(column), src)
}
func (m *structTableModel) ScanColumn(column string, src interface{}) error {
if ok, err := m.scanColumn(column, src); ok {
return err
}
if column == "" || column[0] == '_' || m.db.flags.Has(discardUnknownColumns) {
return nil
}
return fmt.Errorf("bun: %s does not have column %q", m.table.TypeName, column)
}
func (m *structTableModel) scanColumn(column string, src interface{}) (bool, error) {
if src != nil {
if err := m.initStruct(); err != nil {
return true, err
}
}
if field, ok := m.table.FieldMap[column]; ok {
return true, field.ScanValue(m.strct, src)
}
if joinName, column := splitColumn(column); joinName != "" {
if join := m.GetJoin(joinName); join != nil {
return true, join.JoinModel.ScanColumn(column, src)
}
if m.table.ModelName == joinName {
return true, m.ScanColumn(column, src)
}
}
return false, nil
}
func (m *structTableModel) AppendNamedArg(
fmter schema.Formatter, b []byte, name string,
) ([]byte, bool) {
return m.table.AppendNamedArg(fmter, b, name, m.strct)
}
// sqlite3 sometimes does not unquote columns.
func unquote(s string) string {
if s == "" {
return s
}
if s[0] == '"' && s[len(s)-1] == '"' {
return s[1 : len(s)-1]
}
return s
}
func splitColumn(s string) (string, string) {
if i := strings.Index(s, "__"); i >= 0 {
return s[:i], s[i+2:]
}
return "", s
}