0_mutatetest.go

package main

import (
	"context"
	"flag"

	"cloud.google.com/go/datastore"
	"github.com/k0kubun/pp"

	"log"
)

var client *datastore.Client
type Test struct{ Foo string }

func main() {
	withTx := flag.Bool("with-tx", false, "with transaction?")
	kind := flag.String("kind", "", "kind")
	flag.Parse()

	var err error
	ctx := context.Background()
	client, err = datastore.NewClient(ctx, "apstndb-fsds-tokyo")
	if err != nil {
		log.Fatalln(err)
	}
	exec(ctx, *kind, *withTx)
}

func exec(ctx context.Context, kind string, withTx bool) {
	var err error
	key := datastore.NameKey(kind, "foo", nil)
	_, err = client.Mutate(ctx, []*datastore.Mutation{datastore.NewInsert(key, &Test{Foo: "bar"})}...)
	if err != nil {
		log.Println(err)
	}
	var result []Test
	_, err = client.GetAll(ctx, datastore.NewQuery(kind), &result)
	if err != nil {
		log.Println(err)
	}
	pp.Println(result)
	result = []Test{}
	key2 := datastore.NameKey(kind, "bar", nil)

	mutations := []*datastore.Mutation{datastore.NewInsert(key, &Test{Foo: "baz"}), datastore.NewInsert(key2, &Test{Foo: "foobar"})}
	if withTx {
		_, err = client.RunInTransaction(ctx, func(tx *datastore.Transaction) error {
			_, err = tx.Mutate(mutations...)
			return err
		})
	} else {
		_, err = client.Mutate(ctx, mutations...)
	}
	if err != nil {
		log.Println(err)
	}
	_, err = client.GetAll(ctx, datastore.NewQuery(kind), &result)
	if err != nil {
		log.Println(err)
	}
	pp.Println(result)
}

1_log.txt

$ gcloud app describe --project=apstndb-fsds-tokyo --format="value(databaseType)"
CLOUD_DATASTORE_COMPATIBILITY
$ go run ./ --with-tx=false --kind=WithoutTx
[]main.Test{
  main.Test{
    Foo: "bar",
  },
}
2020/01/24 19:03:10 rpc error: code = AlreadyExists desc = entity already exists: app: "b~apstndb-fsds-tokyo"
path <
  Element {
    type: "WithoutTx"
    name: "foo"
  }
>

[]main.Test{
  main.Test{
    Foo: "foobar",
  },
  main.Test{
    Foo: "bar",
  },
}

$ go run ./ --with-tx=true --kind=WithTx
[]main.Test{
  main.Test{
    Foo: "bar",
  },
}
2020/01/24 19:03:48 rpc error: code = AlreadyExists desc = entity already exists: app: "b~apstndb-fsds-tokyo"
path <
  Element {
    type: "WithTx"
    name: "foo"
  }
>

[]main.Test{
  main.Test{
    Foo: "bar",
  },
}