Golang datastore.Delete函數代碼示例

func (self *store) Dequeue(perma_blobref string, blobref string) (blobrefs []string, err os.Error) {
	parent := datastore.NewKey("perma", perma_blobref, 0, nil)
	key := datastore.NewKey("missing", blobref, 0, parent)
	var m missingStruct
	if err = datastore.Get(self.c, key, &m); err != nil {
		if err == datastore.ErrNoSuchEntity {
			return nil, nil
		}
	}
	err = datastore.Delete(self.c, key)
	if err != nil {
		return
	}
	for _, dep := range m.Pending {
		key := datastore.NewKey("pending", dep, 0, parent)
		var p pendingStruct
		if err = datastore.Get(self.c, key, &m); err != nil {
			if err != datastore.ErrNoSuchEntity {
				continue
			}
		}
		p.WaitingForCount--
		if p.WaitingForCount == 0 {
			blobrefs = append(blobrefs, dep)
			datastore.Delete(self.c, key)
		}
	}
	return
}

func solve(w http.ResponseWriter, r *http.Request) {
	context := appengine.NewContext(r)

	j, err := getParamsJeu(r)
	if err != nil {
		w.WriteHeader(http.StatusBadRequest)
		context.Errorf("%s", err)
		return
	}

	if j.CheckJeu() == false {
		context.Errorf("Données du jeu invalide: Plaques: %d, Total: %d", j.Plaques, j.Total)
		w.WriteHeader(http.StatusBadRequest)
		return
	}

	//Generation de la Key
	k := genStringID(j)
	//Netoyage de pending
	err = datastore.RunInTransaction(context, func(c appengine.Context) error {
		var err error
		key := datastore.NewKey(c, PENDING, k, 0, nil)
		if err = datastore.Delete(c, key); err != nil {
			return err
		}
		//Ajout dans ongoing
		key = datastore.NewKey(c, ONGOING, k, 0, nil)
		if _, err = datastore.Put(c, key, &j); err != nil {
			return err
		}

		//Résolution du compte est bon
		var sol solution
		sol.Resultats = j.Resolv()
		sol.Jeu = j

		//Netoyage de ongoing
		key = datastore.NewKey(c, ONGOING, k, 0, nil)
		if err = datastore.Delete(c, key); err != nil {
			return err
		}

		//Ajout dans finised
		key = datastore.NewKey(c, FINISHED, k, 0, nil)
		if _, err = datastore.Put(c, key, &sol); err != nil {
			return err
		}

		return err
	}, &datastore.TransactionOptions{XG: true})

	if err != nil {
		w.WriteHeader(http.StatusInternalServerError)
		context.Errorf("%s", err)
		return
	}
	return
}

// Delete deletes a single record of this type.  Returns nil if successful, otherwise
// the datastore error that was returned.
//   people := NewModel("people")
//   people.Delete(1)
//
// Raises events:
//   Model.BeforeDelete with Args(id, nil)
//   Model.AfterDelete with Args(id, nil)
// Note: The Record will not be passed to the events.
func (m *Model) Delete(id int64) os.Error {

	// trigger the BeforeDeleteByID event
	context := m.BeforeDelete.Trigger(id, nil)

	if !context.Cancel {

		err := datastore.Delete(m.AppEngineContext(), m.NewKeyWithID(id))

		if err == nil {

			// trigger the AfterDeleteByID event
			if m.AfterDelete.HasCallbacks() {
				m.AfterDelete.TriggerWithContext(context)
			}

		}

		// return the error
		return err

	}

	return ErrOperationCancelledByEventCallback

}

// Finds the first matching hot bid in the list, and deletes it. Then, returns
// the corresponding "real" bid.
func findValidBid(c appengine.Context, iter *datastore.Iterator, now time.Time) (*datastore.Key, *Bid, error) {
	for {
		var hot hotBid
		key, e := iter.Next(hotBidCodec{&hot})
		if e == datastore.Done {
			break
		} else if e != nil {
			// Error case
			return nil, nil, e
		}

		if now.Before(hot.Expires) {
			if err := datastore.Delete(c, key); err != nil {
				return nil, nil, err
			}

			var bid Bid
			if err := datastore.Get(c, hot.BidKey, bidCodec{&bid}); err != nil {
				return nil, nil, err
			}
			return hot.BidKey, &bid, nil
		}
	}
	return nil, nil, nil
}

func (self *Mutex) Unlock(c gaecontext.GAEContext) (err error) {
	if err = datastore.Delete(c, lockIdForName(c, self.Name)); err != nil {
		return
	}
	err = memcache.Del(c, lockKeyForName(self.Name))
	return
}

func Cardsetdetail(w http.ResponseWriter, r *http.Request) {
	c := appengine.NewContext(r)

	// get key
	encodedKey := r.FormValue("key")
	decodedKey, err := datastore.DecodeKey(encodedKey)
	if err != nil {
		err.Error()
	}

	// delete mode
	if r.FormValue("action") == "delete" {
		err = datastore.Delete(c, decodedKey)
		if err != nil {
			err.Error()
		}
		http.Redirect(w, r, "/cardsetlist", 303)
	}

	// get cardset
	cardset := new(Cardset)
	err = datastore.Get(c, decodedKey, cardset)
	if err != nil {
		err.Error()
	}

	// output html
	material := make(map[string]string)
	material["Name"] = cardset.Name
	material["Key"] = encodedKey
	Output(w, "page/cardset/cardsetdetail.html", material)
}

// RewriteID transactionally rewrites the Account under the
// correct (i.e., obfuscated) key.
func (a *Account) RewriteID(c appengine.Context, u *user.User) error {
	var err error
	a.ID, err = ID(u)
	if err != nil {
		return fmt.Errorf("couldn't create ID for %v", u)
	}
	var txnErr error
	for i := 0; i < 10; i++ {
		txnErr = datastore.RunInTransaction(c, func(c appengine.Context) error {
			if err := a.Put(c); err != nil {
				return err
			}
			oldKey := datastore.NewKey(c, "UserAccount", u.ID, 0, nil)
			if err := datastore.Delete(c, oldKey); err != nil {
				return err
			}
			return nil
		}, &datastore.TransactionOptions{XG: true})
		if txnErr != datastore.ErrConcurrentTransaction {
			break
		}
	}
	if txnErr != nil {
		return txnErr
	}
	return nil
}

/**
 * データストアから指定された単語を削除する
 * API
 */
func delete(w http.ResponseWriter, r *http.Request) {
	var c appengine.Context
	var u *user.User
	var query *datastore.Query
	var word string
	var iterator *datastore.Iterator
	var key *datastore.Key
	var err error
	var entity Entity

	word = r.FormValue("word")
	if word == "" {
		return
	}

	c = appengine.NewContext(r)
	u = user.Current(c)
	query = datastore.NewQuery("words").Filter("UserID =", u.ID).Filter("Word =", word)
	iterator = query.Run(c)

	for {
		key, err = iterator.Next(&entity)
		if err != nil {
			break
		}
		err = datastore.Delete(c, key)
		Check(c, err)
	}
}

func DeleteInvestment(c appengine.Context, key string) error {
	k, err := datastore.DecodeKey(key)
	if err != nil {
		return err
	}
	return datastore.Delete(c, k)
}

func deleteOneItem(rw http.ResponseWriter, req *http.Request, keyString string) {
	// To access datastore and to log
	c := appengine.NewContext(req)
	c.Infof("deleteOneItem()")

	// Result
	r := http.StatusNoContent
	defer func() {
		// Return status. WriteHeader() must be called before call to Write
		if r == http.StatusNoContent {
			rw.WriteHeader(http.StatusNoContent)
		} else {
			http.Error(rw, http.StatusText(r), r)
		}
	}()

	key, err := datastore.DecodeKey(keyString)
	if err != nil {
		c.Errorf("%s in decoding key string", err)
		r = http.StatusBadRequest
		return
	}

	// Delete the entity
	if err := datastore.Delete(c, key); err != nil {
		c.Errorf("%s, in deleting entity by key", err)
		r = http.StatusNotFound
		return
	}
	c.Infof("Key %s is deleted", keyString)
}

func delete(w http.ResponseWriter, r *http.Request) {
	c := appengine.NewContext(r)
	var dTile Tile
	//	var now Period
	//	datastore.Get(c, currentSemesterKey(c), &now)
	num, e := strconv.Atoi(r.FormValue("num"))
	sem, e1 := strconv.Atoi(r.FormValue("semester"))
	yr, e2 := strconv.Atoi(r.FormValue("year"))
	if e != nil || e1 != nil || e2 != nil {
		panic("shouldn't happen; semester and year guaranteed to be ints")
	}
	k := datastore.NewKey(c, "Tile", strint(r.FormValue("name"), num), 0, tileRootKey(c, sem, yr))
	datastore.Get(c, k, &dTile)
	if u := user.Current(c); !u.Admin {
		http.Redirect(w, r, "/", http.StatusFound)
		return
	} else {
		log.Println("deleting things now...")
		e1 := blobstore.Delete(c, appengine.BlobKey(dTile.Imgref))
		e2 := datastore.Delete(c, k)
		if e1 != nil {
			log.Println("error with blobstore delete")
		}
		if e2 != nil {
			log.Println("error with datastore delete")
		}
	}
	log.Println("redirecting")
	http.Redirect(w, r, "/", http.StatusFound)
}

/**
 * データストアからゲームを削除する
 * 削除を命令したユーザとゲームの所有者が一致していることを事前に確認すること
 * この関數內ではチェックを行わない
 * @param {string} encodedGameKey エンコード済みのゲームキー
 */
func (this *Model) deleteGame(encodedGameKey string) {
	gameKey, err := datastore.DecodeKey(encodedGameKey)
	check(this.c, err)

	err = datastore.Delete(this.c, gameKey)
	check(this.c, err)
}

func deleteAllItem(rw http.ResponseWriter, req *http.Request) {
	// To access datastore and to log
	c := appengine.NewContext(req)
	c.Infof("deleteAll()")

	// Delete root entity after other entities
	r := 0
	pKey := datastore.NewKey(c, ItemKind, ItemRoot, 0, nil)
	if keys, err := datastore.NewQuery(ItemKind).KeysOnly().GetAll(c, nil); err != nil {
		c.Errorf("%s", err)
		r = 1
	} else if err := datastore.DeleteMulti(c, keys); err != nil {
		c.Errorf("%s", err)
		r = 1
	} else if err := datastore.Delete(c, pKey); err != nil {
		c.Errorf("%s", err)
		r = 1
	}

	// Return status. WriteHeader() must be called before call to Write
	if r == 0 {
		rw.WriteHeader(http.StatusOK)
	} else {
		http.Error(rw, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
	}
}

func (f FeedInfo) updateArticles(c appengine.Context, articles Articles) error {
	key := datastore.NewKey(c, feedKind, f.Url, 0, nil)
	q := datastore.NewQuery(articleKind).Ancestor(key).KeysOnly()
	stored := make(map[string]*datastore.Key)
	for it := q.Run(c); ; {
		k, err := it.Next(nil)
		if err == datastore.Done {
			break
		} else if err != nil {
			return err
		}
		stored[k.StringID()] = k
	}

	for _, a := range articles {
		k := datastore.NewKey(c, articleKind, a.StringID(), 0, key)
		id := k.StringID()
		if _, ok := stored[id]; ok {
			delete(stored, id)
			continue
		}
		if _, err := datastore.Put(c, k, &a); err != nil {
			return err
		}
	}

	for _, k := range stored {
		if err := datastore.Delete(c, k); err != nil {
			return err
		}
	}
	return nil
}

func (t *Team) Delete(c appengine.Context) {
	err := datastore.Delete(c, t.Key)
	if err != nil {
		c.Errorf("Error: %v", err)
		return
	}
}