Add cloud datastore implementation.

impl/cloud/datastore_test.go

Index: impl/cloud/datastore_test.go
diff --git a/impl/cloud/datastore_test.go b/impl/cloud/datastore_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..42d7b76eb56838aa3674fbb3eaa57499f8bc4e9d
--- /dev/null
+++ b/impl/cloud/datastore_test.go
@@ -0,0 +1,288 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package cloud
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"os"
+	"testing"
+	"time"
+
+	ds "github.com/luci/gae/service/datastore"
+	"github.com/luci/gae/service/info"
+
+	"github.com/luci/luci-go/common/errors"
+	"golang.org/x/net/context"
+	"google.golang.org/cloud/datastore"
+
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func mkProperties(index bool, vals ...interface{}) []ds.Property {
+	indexSetting := ds.ShouldIndex
+	if !index {
+		indexSetting = ds.NoIndex
+	}
+
+	result := make([]ds.Property, len(vals))
+	for i, v := range vals {
+		result[i].SetValue(v, indexSetting)
+	}
+	return result
+}
+
+func mkp(vals ...interface{}) []ds.Property   { return mkProperties(true, vals...) }
+func mkpNI(vals ...interface{}) []ds.Property { return mkProperties(false, vals...) }
+
+// TestDatastore tests the cloud datastore implementation.
+//
+// This test uses the gcloud datastore emulator. Like the Go datastore package,
+// the emulator must use the gRPC interface. At the time of writing, the
+// emulator included with the "gcloud" tool is an older emulator that does NOT
+// support gRPC.
+//
+// Download the emulator linked here:
+// https://code.google.com/p/google-cloud-sdk/issues/detail?id=719#c3
+//
+// Run it in "--testing" mode, which removes random consistency failures and
+// runs in-memory:
+// $ ./gcd.sh start --testing
+//
+// Export the DATASTORE_EMULATOR_HOST environment variable. By default:
+// $ export DATASTORE_EMULATOR_HOST=localhost:8080
+//
+// If the emulator environment is not detected, this test will be skipped.
+func TestDatastore(t *testing.T) {
+	t.Parallel()
+
+	// See if an emulator is running. If no emulator is running, we will skip this
+	// test suite.
+	emulatorHost := os.Getenv("DATASTORE_EMULATOR_HOST")
+	if emulatorHost == "" {
+		t.Logf("No emulator detected. Skipping test suite.")
+		return
+	}
+
+	Convey(fmt.Sprintf(`A cloud installation using datastore emulator %q`, emulatorHost), t, func() {
+		c := context.Background()
+		client, err := datastore.NewClient(c, "")
+		So(err, ShouldBeNil)
+		defer client.Close()
+
+		testTime := ds.RoundTime(time.Date(2016, 1, 1, 0, 0, 0, 0, time.UTC))
+
+		c = Use(c, client)
+
+		Convey(`Supports namespaces`, func() {
+			namespaces := []string{"foo", "bar", "baz"}
+
+			// Clear all used entities from all namespaces.
+			for _, ns := range namespaces {
+				nsCtx := info.Get(c).MustNamespace(ns)
+				di := ds.Get(nsCtx)
+
+				keys := make([]*ds.Key, len(namespaces))
+				for i := range keys {
+					keys[i] = di.MakeKey("Test", i+1)
+				}
+				So(errors.Filter(di.DeleteMulti(keys), ds.ErrNoSuchEntity), ShouldBeNil)
+			}
+
+			// Put one entity per namespace.
+			for i, ns := range namespaces {
+				nsCtx := info.Get(c).MustNamespace(ns)
+
+				pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp(i + 1), "Value": mkp(i)}
+				So(ds.Get(nsCtx).Put(pmap), ShouldBeNil)
+			}
+
+			// Make sure that entity only exists in that namespace.
+			for _, ns := range namespaces {
+				nsCtx := info.Get(c).MustNamespace(ns)
+
+				for i := range namespaces {
+					pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp(i + 1)}
+					err := ds.Get(nsCtx).Get(pmap)
+
+					if namespaces[i] == ns {
+						So(err, ShouldBeNil)
+					} else {
+						So(err, ShouldEqual, ds.ErrNoSuchEntity)
+					}
+				}
+			}
+		})
+
+		Convey(`In a clean random testing namespace`, func() {
+			// Enter a namespace for this round of tests.
+			randNamespace := make([]byte, 32)
+			if _, err := rand.Read(randNamespace); err != nil {
+				panic(err)
+			}
+			c = info.Get(c).MustNamespace(fmt.Sprintf("testing-%s", hex.EncodeToString(randNamespace)))
+			di := ds.Get(c)
+
+			// Execute a kindless query to clear the namespace.
+			q := ds.NewQuery("").KeysOnly(true)
+			var allKeys []*ds.Key
+			So(di.GetAll(q, &allKeys), ShouldBeNil)
+			So(di.DeleteMulti(allKeys), ShouldBeNil)
+
+			Convey(`Can allocate an ID range`, func() {
+				// The datastore emulator does not allocate a contiguous ID space.
+				// Consequently, we will test with allocation sizes of 1 so the contiguous
+				// assumption is never violated.
+				//
+				// TODO: Re-work allocate IDs API to allow for non-contiugous IDs.
+				idx, err := di.AllocateIDs(di.MakeKey("Foo", "12", "Bar", 0), 1)
+				So(err, ShouldBeNil)
+				So(idx, ShouldBeGreaterThanOrEqualTo, 0)
+
+				next, err := di.AllocateIDs(di.MakeKey("Foo", "12", "Bar", 0), 1)
+				So(err, ShouldBeNil)
+				So(next, ShouldNotEqual, idx)
+			})
+
+			Convey(`Can get, put, and delete entities`, func() {
+				// Put: "foo", "bar", "baz".
+				put := []ds.PropertyMap{
+					{"$kind": mkp("test"), "$id": mkp("foo"), "Value": mkp(1337)},
+					{"$kind": mkp("test"), "$id": mkp("bar"), "Value": mkp(42)},
+					{"$kind": mkp("test"), "$id": mkp("baz"), "Value": mkp(0xd065)},
+				}
+				So(di.PutMulti(put), ShouldBeNil)
+				delete(put[0], "$key")
+				delete(put[1], "$key")
+				delete(put[2], "$key")
+
+				// Delete: "bar".
+				So(di.Delete(di.MakeKey("test", "bar")), ShouldBeNil)
+
+				// Get: "foo", "bar", "baz"
+				get := []ds.PropertyMap{
+					{"$kind": mkp("test"), "$id": mkp("foo")},
+					{"$kind": mkp("test"), "$id": mkp("bar")},
+					{"$kind": mkp("test"), "$id": mkp("baz")},
+				}
+
+				err := di.GetMulti(get)
+				So(err, ShouldHaveSameTypeAs, errors.MultiError(nil))
+
+				merr := err.(errors.MultiError)
+				So(len(merr), ShouldEqual, 3)
+				So(merr[0], ShouldBeNil)
+				So(merr[1], ShouldEqual, ds.ErrNoSuchEntity)
+				So(merr[2], ShouldBeNil)
+
+				// put[1] will not be retrieved (delete)
+				put[1] = get[1]
+				So(get, ShouldResemble, put)
+			})
+
+			Convey(`Can put and get all supported entity fields.`, func() {
+				put := ds.PropertyMap{
+					"$id":    mkpNI("foo"),
+					"$kind":  mkpNI("FooType"),
+					"Number": mkp(1337),
+					"String": mkpNI("hello"),
+					"Bytes":  mkp([]byte("world")),
+					"Time":   mkp(testTime),
+					"Float":  mkpNI(3.14),
+					"Key":    mkp(di.MakeKey("Parent", "ParentID", "Child", 1337)),
+
+					"ComplexSlice": mkp(1337, "string", []byte("bytes"), testTime, float32(3.14),
+						float64(2.71), true, di.MakeKey("SomeKey", "SomeID")),
+				}
+				So(di.Put(put), ShouldBeNil)
+				delete(put, "$key")
+
+				get := ds.PropertyMap{
+					"$id":   mkpNI("foo"),
+					"$kind": mkpNI("FooType"),
+				}
+				So(di.Get(get), ShouldBeNil)
+				So(get, ShouldResemble, put)
+			})
+
+			Convey(`With several entities installed`, func() {
+				So(di.PutMulti([]ds.PropertyMap{
+					{"$kind": mkp("Test"), "$id": mkp("foo"), "FooBar": mkp(true)},
+					{"$kind": mkp("Test"), "$id": mkp("bar"), "FooBar": mkp(true)},
+					{"$kind": mkp("Test"), "$id": mkp("baz")},
+					{"$kind": mkp("Test"), "$id": mkp("qux")},
+				}), ShouldBeNil)
+
+				q := ds.NewQuery("Test")
+
+				Convey(`Can query for entities with FooBar == true.`, func() {
+					var results []ds.PropertyMap
+					q = q.Eq("FooBar", true)
+					So(di.GetAll(q, &results), ShouldBeNil)
+
+					So(results, ShouldResemble, []ds.PropertyMap{
+						{"$key": mkpNI(di.MakeKey("Test", "bar")), "FooBar": mkp(true)},
+						{"$key": mkpNI(di.MakeKey("Test", "foo")), "FooBar": mkp(true)},
+					})
+				})
+
+				Convey(`Can query for entities whose __key__ > "baz".`, func() {
+					var results []ds.PropertyMap
+					q = q.Gt("__key__", di.MakeKey("Test", "baz"))
+					So(di.GetAll(q, &results), ShouldBeNil)
+
+					So(results, ShouldResemble, []ds.PropertyMap{
+						{"$key": mkpNI(di.MakeKey("Test", "foo")), "FooBar": mkp(true)},
+						{"$key": mkpNI(di.MakeKey("Test", "qux"))},
+					})
+				})
+
+				Convey(`Can transactionally get and put.`, func() {
+					err := di.RunInTransaction(func(c context.Context) error {
+						di := ds.Get(c)
+
+						pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp("qux")}
+						if err := di.Get(pmap); err != nil {
+							return err
+						}
+
+						pmap["ExtraField"] = mkp("Present!")
+						return di.Put(pmap)
+					}, nil)
+					So(err, ShouldBeNil)
+
+					pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp("qux")}
+					err = di.RunInTransaction(func(c context.Context) error {
+						return ds.Get(c).Get(pmap)
+					}, nil)
+					So(err, ShouldBeNil)
+					So(pmap, ShouldResemble, ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp("qux"), "ExtraField": mkp("Present!")})
+				})
+
+				Convey(`Can fail in a transaction with no effect.`, func() {
+					testError := errors.New("test error")
+
+					err := di.RunInTransaction(func(c context.Context) error {
+						di := ds.Get(c)
+
+						pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp("quux")}
+						if err := di.Put(pmap); err != nil {
+							return err
+						}
+						return testError
+					}, nil)
+					So(err, ShouldEqual, testError)
+
+					pmap := ds.PropertyMap{"$kind": mkp("Test"), "$id": mkp("quux")}
+					err = di.RunInTransaction(func(c context.Context) error {
+						return ds.Get(c).Get(pmap)
+					}, nil)
+					So(err, ShouldEqual, ds.ErrNoSuchEntity)
+				})
+			})
+		})
+	})
+}