|
- // Copyright 2018 Google LLC
- //
- // 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 datastore
-
- import (
- "fmt"
-
- pb "google.golang.org/genproto/googleapis/datastore/v1"
- )
-
- // A Mutation represents a change to a Datastore entity.
- type Mutation struct {
- key *Key // needed for transaction PendingKeys and to dedup deletions
- mut *pb.Mutation
- err error
- }
-
- func (m *Mutation) isDelete() bool {
- _, ok := m.mut.Operation.(*pb.Mutation_Delete)
- return ok
- }
-
- // NewInsert creates a mutation that will save the entity src into the datastore with
- // key k, returning an error if k already exists.
- // See Client.Put for valid values of src.
- func NewInsert(k *Key, src interface{}) *Mutation {
- if !k.valid() {
- return &Mutation{err: ErrInvalidKey}
- }
- p, err := saveEntity(k, src)
- if err != nil {
- return &Mutation{err: err}
- }
- return &Mutation{
- key: k,
- mut: &pb.Mutation{Operation: &pb.Mutation_Insert{Insert: p}},
- }
- }
-
- // NewUpsert creates a mutation that saves the entity src into the datastore with key
- // k, whether or not k exists. See Client.Put for valid values of src.
- func NewUpsert(k *Key, src interface{}) *Mutation {
- if !k.valid() {
- return &Mutation{err: ErrInvalidKey}
- }
- p, err := saveEntity(k, src)
- if err != nil {
- return &Mutation{err: err}
- }
- return &Mutation{
- key: k,
- mut: &pb.Mutation{Operation: &pb.Mutation_Upsert{Upsert: p}},
- }
- }
-
- // NewUpdate creates a mutation that replaces the entity in the datastore with key k,
- // returning an error if k does not exist. See Client.Put for valid values of src.
- func NewUpdate(k *Key, src interface{}) *Mutation {
- if !k.valid() {
- return &Mutation{err: ErrInvalidKey}
- }
- if k.Incomplete() {
- return &Mutation{err: fmt.Errorf("datastore: can't update the incomplete key: %v", k)}
- }
- p, err := saveEntity(k, src)
- if err != nil {
- return &Mutation{err: err}
- }
- return &Mutation{
- key: k,
- mut: &pb.Mutation{Operation: &pb.Mutation_Update{Update: p}},
- }
- }
-
- // NewDelete creates a mutation that deletes the entity with key k.
- func NewDelete(k *Key) *Mutation {
- if !k.valid() {
- return &Mutation{err: ErrInvalidKey}
- }
- if k.Incomplete() {
- return &Mutation{err: fmt.Errorf("datastore: can't delete the incomplete key: %v", k)}
- }
- return &Mutation{
- key: k,
- mut: &pb.Mutation{Operation: &pb.Mutation_Delete{Delete: keyToProto(k)}},
- }
- }
-
- func mutationProtos(muts []*Mutation) ([]*pb.Mutation, error) {
- // If any of the mutations have errors, collect and return them.
- var merr MultiError
- for i, m := range muts {
- if m.err != nil {
- if merr == nil {
- merr = make(MultiError, len(muts))
- }
- merr[i] = m.err
- }
- }
- if merr != nil {
- return nil, merr
- }
- var protos []*pb.Mutation
- // Collect protos. Remove duplicate deletions (see deleteMutations).
- seen := map[string]bool{}
- for _, m := range muts {
- if m.isDelete() {
- ks := m.key.String()
- if seen[ks] {
- continue
- }
- seen[ks] = true
- }
- protos = append(protos, m.mut)
- }
- return protos, nil
- }
|