initial commit

Signed-off-by: Derek McQuay <derekmcquay@gmail.com>

vendor/cloud.google.com/go/datastore/mutation.go

@@ -0,0 +1,129 @@
+// Copyright 2018 Google Inc. All Rights Reserved.
+//
+// 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
+}