Simple memory testing for gae/wrapper

go/src/infra/gae/libs/wrapper/memory/datastore_test.go

Index: go/src/infra/gae/libs/wrapper/memory/datastore_test.go
diff --git a/go/src/infra/gae/libs/wrapper/memory/datastore_test.go b/go/src/infra/gae/libs/wrapper/memory/datastore_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..eec91eb7883c27844a7ee8f3a44b5fc92ab78d14
--- /dev/null
+++ b/go/src/infra/gae/libs/wrapper/memory/datastore_test.go
@@ -0,0 +1,524 @@
+// Copyright 2015 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 memory
+
+import (
+	"fmt"
+	"infra/gae/libs/meta"
+	"infra/gae/libs/wrapper"
+	"testing"
+
+	. "github.com/smartystreets/goconvey/convey"
+	"golang.org/x/net/context"
+
+	"appengine/datastore"
+)
+
+func TestDatastoreKinder(t *testing.T) {
+	t.Parallel()
+
+	Convey("Datastore kinds and keys", t, func() {
+		c := Use(Enable(context.Background()))
+		ds := wrapper.GetDS(c)
+		So(ds, ShouldNotBeNil)
+
+		Convey("implements DSKinder", func() {
+			type Foo struct{}
+			So(ds.Kind(&Foo{}), ShouldEqual, "Foo")
+
+			Convey("which can be tweaked by DSKindSetter", func() {
+				ds.SetKindNameResolver(func(interface{}) string { return "spam" })
+				So(ds.Kind(&Foo{}), ShouldEqual, "spam")
+
+				Convey("and it retains the function so you can stack them", func() {
+					cur := ds.KindNameResolver()
+					ds.SetKindNameResolver(func(o interface{}) string { return "wat" + cur(o) })
+					So(ds.Kind(&Foo{}), ShouldEqual, "watspam")
+				})
+			})
+		})
+
+		Convey("implements DSNewKeyer", func() {
+			Convey("NewKey", func() {
+				key := ds.NewKey("nerd", "stringID", 0, nil)
+				So(key, ShouldNotBeNil)
+				So(key.Kind(), ShouldEqual, "nerd")
+				So(key.StringID(), ShouldEqual, "stringID")
+				So(key.IntID(), ShouldEqual, 0)
+				So(key.Parent(), ShouldBeNil)
+				So(key.AppID(), ShouldEqual, "dev~my~app")
+				So(key.Namespace(), ShouldEqual, "")
+				So(key.String(), ShouldEqual, "/nerd,stringID")
+				So(key.Incomplete(), ShouldBeFalse)
+				So(KeyValid("", key, UserKeyOnly), ShouldBeTrue)
+
+				chkey := ds.NewKey("wat", "", 100, key)
+				So(chkey, ShouldNotBeNil)
+				So(chkey.Kind(), ShouldEqual, "wat")
+				So(chkey.StringID(), ShouldEqual, "")
+				So(chkey.IntID(), ShouldEqual, 100)
+				So(chkey.Parent(), ShouldEqual, key)
+				So(chkey.AppID(), ShouldEqual, "dev~my~app")
+				So(chkey.Namespace(), ShouldEqual, "")
+				So(chkey.String(), ShouldEqual, "/nerd,stringID/wat,100")
+				So(key.Incomplete(), ShouldBeFalse)
+				So(KeyValid("", chkey, UserKeyOnly), ShouldBeTrue)
+
+				incompl := ds.NewKey("sup", "", 0, key)
+				So(incompl, ShouldNotBeNil)
+				So(incompl.Incomplete(), ShouldBeTrue)
+				So(KeyValid("", incompl, UserKeyOnly), ShouldBeTrue)
+				So(incompl.String(), ShouldEqual, "/nerd,stringID/sup,0")
+
+				bad := ds.NewKey("nooo", "", 10, incompl)
+				So(bad, ShouldNotBeNil)
+				So(bad.Incomplete(), ShouldBeFalse)
+				So(KeyValid("", bad, UserKeyOnly), ShouldBeFalse)
+				So(bad.String(), ShouldEqual, "/nerd,stringID/sup,0/nooo,10")
+
+				So(rootKey(bad), ShouldEqual, key)
+
+				Convey("other key validation", func() {
+					So(KeyValid("", nil, UserKeyOnly), ShouldBeFalse)
+
+					key := ds.NewKey("", "", 0, nil)
+					So(key, ShouldNotBeNil)
+
+					So(KeyValid("", key, UserKeyOnly), ShouldBeFalse)
+
+					key = ds.NewKey("noop", "power level", 9000, nil)
+					So(key, ShouldNotBeNil)
+
+					So(KeyValid("", key, UserKeyOnly), ShouldBeFalse)
+				})
+			})
+
+			Convey("NewKeyObj", func() {
+				type Foo struct {
+					_knd   string         `goon:"kind,coool"`
+					ID     int64          `goon:"id"`
+					Parent *datastore.Key `goon:"parent"`
+				}
+				f := &Foo{ID: 100}
+				k := ds.NewKeyObj(f)
+				So(k.String(), ShouldEqual, "/coool,100")
+
+				f.Parent = k
+				f._knd = "weevils"
+				f.ID = 19
+				k = ds.NewKeyObj(f)
+				So(k.String(), ShouldEqual, "/coool,100/weevils,19")
+
+				Convey("panics when you do a dumb thing", func() {
+					type Foo struct {
+						ID []byte `goon:"id"`
+					}
+					So(func() { ds.NewKeyObj(&Foo{}) }, ShouldPanic)
+				})
+			})
+
+			Convey("NewKeyObjError", func() {
+				type Foo struct {
+					ID []byte `goon:"id"`
+				}
+				_, err := ds.NewKeyObjError(&Foo{})
+				So(err.Error(), ShouldContainSubstring, "must be int64 or string")
+			})
+		})
+
+	})
+}
+
+func TestDatastoreSingleReadWriter(t *testing.T) {
+	t.Parallel()
+
+	Convey("Datastore single reads and writes", t, func() {
+		c := Use(Enable(context.Background()))
+		ds := wrapper.GetDS(c)
+		So(ds, ShouldNotBeNil)
+
+		Convey("implements DSSingleReadWriter", func() {
+			type Foo struct {
+				ID     int64          `goon:"id" datastore:"-"`
+				Parent *datastore.Key `goon:"parent" datastore:"-"`
+				Val    int
+			}
+
+			Convey("invalid keys break", func() {
+				k := ds.NewKeyObj(&Foo{})
+				f := &Foo{Parent: k}
+				So(ds.Get(f), ShouldEqual, datastore.ErrInvalidKey)
+
+				_, err := ds.Put(f)
+				So(err, ShouldEqual, datastore.ErrInvalidKey)
+			})
+
+			Convey("getting objects that DNE is an error", func() {
+				So(ds.Get(&Foo{ID: 1}), ShouldEqual, datastore.ErrNoSuchEntity)
+			})
+
+			Convey("Can Put stuff", func() {
+				// with an incomplete key!
+				f := &Foo{Val: 10}
+				k, err := ds.Put(f)
+				So(err, ShouldBeNil)
+				So(k.String(), ShouldEqual, "/Foo,1")
+				So(ds.NewKeyObj(f), ShouldResemble, k)
+
+				Convey("and Get it back", func() {
+					newFoo := &Foo{ID: 1}
+					err := ds.Get(newFoo)
+					So(err, ShouldBeNil)
+					So(newFoo, ShouldResemble, f)
+
+					Convey("and we can Delete it", func() {
+						err := ds.Delete(ds.NewKey("Foo", "", 1, nil))
+						So(err, ShouldBeNil)
+
+						err = ds.Get(newFoo)
+						So(err, ShouldEqual, datastore.ErrNoSuchEntity)
+					})
+				})
+				Convey("Deleteing with a bogus key is bad", func() {
+					err := ds.Delete(ds.NewKey("Foo", "wat", 100, nil))
+					So(err, ShouldEqual, datastore.ErrInvalidKey)
+				})
+				Convey("Deleteing a DNE entity is fine", func() {
+					err := ds.Delete(ds.NewKey("Foo", "wat", 0, nil))
+					So(err, ShouldBeNil)
+				})
+
+				Convey("serialization breaks in the normal ways", func() {
+					type BadFoo struct {
+						_kind string `goon:"kind,Foo"`
+						ID    int64  `goon:"id" datastore:"-"`
+						Val   uint8
+					}
+					_, err := ds.Put(&BadFoo{})
+					So(err.Error(), ShouldContainSubstring,
+						"unsupported struct field type: uint8")
+
+					err = ds.Get(&BadFoo{ID: 1})
+					So(err.Error(), ShouldContainSubstring,
+						"type mismatch: int versus uint8")
+				})
+
+				Convey("check that metadata works", func() {
+					val, _ := meta.GetEntityGroupVersion(c, k)
+					So(val, ShouldEqual, 1)
+
+					for i := 0; i < 10; i++ {
+						_, err = ds.Put(&Foo{Val: 10, Parent: k})
+						So(err, ShouldBeNil)
+					}
+					val, _ = meta.GetEntityGroupVersion(c, k)
+					So(val, ShouldEqual, 11)
+
+					Convey("ensure that group versions persist across deletes", func() {
+						So(ds.Delete(k), ShouldBeNil)
+						for i := int64(1); i < 11; i++ {
+							So(ds.Delete(ds.NewKey("Foo", "", i, k)), ShouldBeNil)
+						}
+						// TODO(riannucci): replace with a Count query instead of this cast
+						ents := ds.(*dsImpl).data.store.GetCollection("ents:")
+						num, _ := ents.GetTotals()
+						// /__entity_root_ids__,Foo
+						// /Foo,1/__entity_group__,1
+						// /Foo,1/__entity_group_ids__,1
+						So(num, ShouldEqual, 3)
+
+						version, err := curVersion(ents, groupMetaKey(k))
+						So(err, ShouldBeNil)
+						So(version, ShouldEqual, 22)
+
+						k, err := ds.Put(f)
+						So(err, ShouldBeNil)
+						val, _ := meta.GetEntityGroupVersion(c, k)
+						So(val, ShouldEqual, 23)
+					})
+				})
+			})
+		})
+
+		Convey("implements DSTransactioner", func() {
+			type Foo struct {
+				ID     int64          `goon:"id" datastore:"-"`
+				Parent *datastore.Key `goon:"parent" datastore:"-"`
+				Val    int
+			}
+			Convey("Put", func() {
+				f := &Foo{Val: 10}
+				k, err := ds.Put(f)
+				So(err, ShouldBeNil)
+				So(k.String(), ShouldEqual, "/Foo,1")
+				So(ds.NewKeyObj(f), ShouldResemble, k)
+
+				Convey("can Put new entity groups", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						ds := wrapper.GetDS(c)
+						So(ds, ShouldNotBeNil)
+
+						f1 := &Foo{Val: 100}
+						k, err := ds.Put(f1)
+						So(err, ShouldBeNil)
+						So(k.String(), ShouldEqual, "/Foo,2")
+
+						f2 := &Foo{Val: 200}
+						k, err = ds.Put(f2)
+						So(err, ShouldBeNil)
+						So(k.String(), ShouldEqual, "/Foo,3")
+
+						return nil
+					}, &datastore.TransactionOptions{XG: true})
+					So(err, ShouldBeNil)
+
+					f := &Foo{ID: 2}
+					So(ds.Get(f), ShouldBeNil)
+					So(f.Val, ShouldEqual, 100)
+
+					f = &Foo{ID: 3}
+					So(ds.Get(f), ShouldBeNil)
+					So(f.Val, ShouldEqual, 200)
+				})
+
+				Convey("can Put new entities in a current group", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						ds := wrapper.GetDS(c)
+						So(ds, ShouldNotBeNil)
+
+						f1 := &Foo{Val: 100, Parent: ds.NewKeyObj(f)}
+						k, err := ds.Put(f1)
+						So(err, ShouldBeNil)
+						So(k.String(), ShouldEqual, "/Foo,1/Foo,1")
+
+						f2 := &Foo{Val: 200, Parent: ds.NewKeyObj(f)}
+						k, err = ds.Put(f2)
+						So(err, ShouldBeNil)
+						So(k.String(), ShouldEqual, "/Foo,1/Foo,2")
+
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+
+					f1 := &Foo{ID: 1, Parent: ds.NewKeyObj(&Foo{ID: 1})}
+					So(ds.Get(f1), ShouldBeNil)
+					So(f1.Val, ShouldEqual, 100)
+
+					f2 := &Foo{ID: 2, Parent: f1.Parent}
+					So(ds.Get(f2), ShouldBeNil)
+					So(f2.Val, ShouldEqual, 200)
+				})
+
+				Convey("Deletes work too", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						ds := wrapper.GetDS(c)
+						So(ds, ShouldNotBeNil)
+						So(ds.Delete(ds.NewKeyObj(f)), ShouldBeNil)
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+					So(ds.Get(f), ShouldEqual, datastore.ErrNoSuchEntity)
+				})
+
+				Convey("A Get counts against your group count", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						ds := wrapper.GetDS(c)
+						f := &Foo{ID: 20}
+						So(ds.Get(f), ShouldEqual, datastore.ErrNoSuchEntity)
+
+						f.ID = 1
+						So(ds.Get(f).Error(), ShouldContainSubstring, "cross-group")
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+				})
+
+				Convey("Get takes a snapshot", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						txnDS := wrapper.GetDS(c)
+						So(txnDS, ShouldNotBeNil)
+
+						f := &Foo{ID: 1}
+						So(txnDS.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+
+						// Don't ever do this in a real program unless you want to guarantee
+						// a failed transaction :)
+						f.Val = 11
+						_, err := ds.Put(f)
+						So(err, ShouldBeNil)
+
+						So(txnDS.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+
+					f := &Foo{ID: 1}
+					So(ds.Get(f), ShouldBeNil)
+					So(f.Val, ShouldEqual, 11)
+
+				})
+
+				Convey("and snapshots are consistent even after Puts", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						txnDS := wrapper.GetDS(c)
+						So(txnDS, ShouldNotBeNil)
+
+						f := &Foo{ID: 1}
+						So(txnDS.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+
+						// Don't ever do this in a real program unless you want to guarantee
+						// a failed transaction :)
+						f.Val = 11
+						_, err := ds.Put(f)
+						So(err, ShouldBeNil)
+
+						So(txnDS.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+
+						f.Val = 20
+						_, err = txnDS.Put(f)
+						So(err, ShouldBeNil)
+
+						So(txnDS.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10) // still gets 10
+
+						return nil
+					}, nil)
+					So(err.Error(), ShouldContainSubstring, "concurrent")
+
+					f := &Foo{ID: 1}
+					So(ds.Get(f), ShouldBeNil)
+					So(f.Val, ShouldEqual, 11)
+				})
+
+				Convey("Reusing a transaction context is bad news", func() {
+					var txnDS wrapper.Datastore
+					err := ds.RunInTransaction(func(c context.Context) error {
+						txnDS = wrapper.GetDS(c)
+						So(txnDS.Get(&Foo{ID: 1}), ShouldBeNil)
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+					So(txnDS.Get(&Foo{ID: 1}).Error(), ShouldContainSubstring, "expired")
+				})
+
+				Convey("Nested transactions are rejected", func() {
+					err := ds.RunInTransaction(func(c context.Context) error {
+						err := wrapper.GetDS(c).RunInTransaction(func(c context.Context) error {
+							panic("noooo")
+						}, nil)
+						So(err.Error(), ShouldContainSubstring, "nested transactions")
+						return nil
+					}, nil)
+					So(err, ShouldBeNil)
+				})
+
+				Convey("Concurrent transactions only accept one set of changes", func() {
+					// Note: I think this implementation is actually /slightly/ wrong.
+					// Accorting to my read of the docs for appengine, when you open a
+					// transaction it actually (essentially) holds a reference to the
+					// entire datastore. Our implementation takes a snapshot of the
+					// entity group as soon as something observes/affects it.
+					//
+					// That said... I'm not sure if there's really a semantic difference.
+					err := ds.RunInTransaction(func(c context.Context) error {
+						txnDS := wrapper.GetDS(c)
+						f := &Foo{ID: 1, Val: 21}
+						_, err = txnDS.Put(f)
+						So(err, ShouldBeNil)
+
+						err := ds.RunInTransaction(func(c context.Context) error {
+							txnDS := wrapper.GetDS(c)
+							f := &Foo{ID: 1, Val: 27}
+							_, err := txnDS.Put(f)
+							So(err, ShouldBeNil)
+							return nil
+						}, nil)
+						So(err, ShouldBeNil)
+
+						return nil
+					}, nil)
+					So(err.Error(), ShouldContainSubstring, "concurrent")
+
+					f := &Foo{ID: 1}
+					So(ds.Get(f), ShouldBeNil)
+					So(f.Val, ShouldEqual, 27)
+				})
+
+				Convey("XG", func() {
+					Convey("Modifying two groups with XG=false is invalid", func() {
+						err := ds.RunInTransaction(func(c context.Context) error {
+							ds := wrapper.GetDS(c)
+							f := &Foo{ID: 1, Val: 200}
+							_, err := ds.Put(f)
+							So(err, ShouldBeNil)
+
+							f.ID = 2
+							_, err = ds.Put(f)
+							So(err.Error(), ShouldContainSubstring, "cross-group")
+							return err
+						}, nil)
+						So(err.Error(), ShouldContainSubstring, "cross-group")
+					})
+
+					Convey("Modifying >25 groups with XG=true is invald", func() {
+						err := ds.RunInTransaction(func(c context.Context) error {
+							ds := wrapper.GetDS(c)
+							for i := int64(1); i < 26; i++ {
+								f := &Foo{ID: i, Val: 200}
+								_, err := ds.Put(f)
+								So(err, ShouldBeNil)
+							}
+							f := &Foo{ID: 27, Val: 200}
+							_, err := ds.Put(f)
+							So(err.Error(), ShouldContainSubstring, "too many entity groups")
+							return err
+						}, &datastore.TransactionOptions{XG: true})
+						So(err.Error(), ShouldContainSubstring, "too many entity groups")
+					})
+				})
+
+				Convey("Errors and panics", func() {
+					Convey("returning an error aborts", func() {
+						err := ds.RunInTransaction(func(c context.Context) error {
+							ds := wrapper.GetDS(c)
+							f := &Foo{ID: 1, Val: 200}
+							_, err := ds.Put(f)
+							So(err, ShouldBeNil)
+
+							return fmt.Errorf("thingy")
+						}, nil)
+						So(err.Error(), ShouldEqual, "thingy")
+
+						f := &Foo{ID: 1}
+						So(ds.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+					})
+
+					Convey("panicing aborts", func() {
+						So(func() {
+							ds.RunInTransaction(func(c context.Context) error {
+								ds := wrapper.GetDS(c)
+								f := &Foo{ID: 1, Val: 200}
+								_, err := ds.Put(f)
+								So(err, ShouldBeNil)
+								panic("wheeeeee")
+							}, nil)
+						}, ShouldPanic)
+
+						f := &Foo{ID: 1}
+						So(ds.Get(f), ShouldBeNil)
+						So(f.Val, ShouldEqual, 10)
+					})
+				})
+			})
+		})
+
+	})
+}