surrealpatch/db/delete.go
2017-03-03 21:39:37 +00:00

106 lines
2.2 KiB
Go

// Copyright © 2016 Abcum Ltd
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package db
import (
"fmt"
"context"
"github.com/abcum/surreal/sql"
"github.com/abcum/surreal/util/item"
"github.com/abcum/surreal/util/keys"
)
func (e *executor) executeDeleteStatement(ctx context.Context, ast *sql.DeleteStatement) (out []interface{}, err error) {
for k, w := range ast.What {
if what, ok := w.(*sql.Param); ok {
ast.What[k] = e.get(what.ID)
}
}
for _, w := range ast.What {
switch what := w.(type) {
default:
return out, fmt.Errorf("Can not execute DELETE query using value '%v' with type '%T'", what, what)
case *sql.Thing:
key := &keys.Thing{KV: ast.KV, NS: ast.NS, DB: ast.DB, TB: what.TB, ID: what.ID}
kv, _ := e.txn.Get(0, key.Encode())
doc := item.New(kv, e.txn, key, e.ctx)
if ret, err := delete(doc, ast); err != nil {
return nil, err
} else if ret != nil {
out = append(out, ret)
}
case *sql.Table:
key := &keys.Table{KV: ast.KV, NS: ast.NS, DB: ast.DB, TB: what.TB}
kvs, _ := e.txn.GetL(0, key.Encode())
for _, kv := range kvs {
doc := item.New(kv, e.txn, nil, e.ctx)
if ret, err := delete(doc, ast); err != nil {
return nil, err
} else if ret != nil {
out = append(out, ret)
}
}
}
}
return
}
func delete(doc *item.Doc, ast *sql.DeleteStatement) (out interface{}, err error) {
if !doc.Check(ast.Cond) {
return
}
if !doc.Allow("DELETE") {
return
}
if err = doc.Erase(); err != nil {
return
}
if err = doc.PurgeIndex(); err != nil {
return
}
if err = doc.PurgeThing(); err != nil {
return
}
if ast.Hard {
if err = doc.PurgePatch(); err != nil {
return
}
}
out = doc.Yield(ast.Echo)
return
}