Question

风景是，我需要从数据存储中检索一些数据，模型是：

class Player(ndb.Model):
    """Models an individual Player with key."""
    chatId = ndb.StringProperty()
    nickname = ndb.StringProperty()
    firstName = ndb.StringProperty()
    lastName = ndb.StringProperty()
    profilePic = ndb.StringProperty()
    conversationStatus = ndb.IntegerProperty(default=ConversationStatus.IDLE)
    contacts = ndb.KeyProperty(kind="Player", repeated=True)

我想使用“联系人”中的按键来检索玩家。属性。

功能＆＃39; pageSearchResults＆＃39;旨在根据页面大小显示有限的结果集。该功能定义如下

prevCursorStr = payload['prev_cursor'] if 'prev_cursor' in payload else ""
nextCursorStr = payload['next_cursor'] if 'next_cursor' in payload else ""
players = []
resultsToFetch = 2

if not prevCursorStr and not nextCursorStr:
    players, next_cursor, more = query.order(Player.key).fetch_page(resultsToFetch)
    prevCursorStr = ""
    if next_cursor:
        nextCursorStr = next_cursor.urlsafe() 
    else:
        next_cursor_str = ""
    next_ = True if more else False
    prev = False
elif nextCursorStr:
    cursor = ndb.Cursor(urlsafe=nextCursorStr)
    players, next_cursor, more = query.order(Player.key).fetch_page(resultsToFetch, start_cursor=cursor)
    prevCursorStr = nextCursorStr
    nextCursorStr = next_cursor.urlsafe()
    prev = True
    next_ = True if more else False
elif prevCursorStr:
    cursor = ndb.Cursor(urlsafe=prevCursorStr)
    players, next_cursor, more = query.order(-Player.key).fetch_page(resultsToFetch, start_cursor=cursor)
    players.reverse()
    nextCursorStr = prevCursorStr
    prevCursorStr = next_cursor.urlsafe()
    prev = True if more else False
    next_ = True



result = {
    'players': players,
    'search': payload['search'] if 'search' in payload else "",
    'next_cursor': nextCursorStr if next_ else "",
    'prev_cursor': prevCursorStr if prev else "",
}


return result

我们假设我做了以下事情：

keys = player.contacts
query = Player.query(Player.key.IN(keys))
return self.pageSearchResults(query, payload)

在这种情况下，我有一个奇怪的问题，分页按顺序正常工作，它给我回到结果列表，如： 1,2， - ＆gt;下一页＆lt; - prev page 3

如果我点击上一页，相同的功能会让我回来 3 - ＆gt;下一页这是不正确的。

现在，如果我查询的属性不是KeyProperty，问题就会消失。

出于调试目的，我将此代码添加到上一个代码段

keys = player.contacts
chatids = []
for key in keys:
    player = key.get()
    chatids.append(player.chatId)

query = Player.query(Player.chatId.IN(chatIds))
return self.pageSearchResults(query, payload)

在这种情况下，我查询chatId StringProperty，分页就像魅力一样。

我真的不明白这里发生了什么，有人可以帮助我吗？

Answer 1

模型的关键属性应按以下方式过滤：

keys = player.contacts
query = Player.query(Player._key.IN(keys))
return self.pageSearchResults(query, payload)

请注意_key。对于与密钥匹配的联系人：

query = Player.query(Player.contacts.IN(keys))

按键查询时，分页会导致ndb问题

1 个答案: