起源
下午在写一个Python连接MongoDB的工具(使用pymongo 3.2).并且使用Python 3.4.但是遇到一个问题，就是调用的时候，发现报错.
报错的程序如下:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 | def findAll(self, **kwargs): print(kwargs) limit = kwargs.get('limit', None) skip = kwargs.get('skip', None) query = kwargs.get('query', None) sortQuery = kwargs.get('sortQuery', None) if self.dbname: collections = self.collection db = self.getDB() print(limit, skip) resultData = None def findPage(self, limit, skip): # 分页查询数据 print(limit, skip) if isinstance(limit, int) and isinstance(skip, int): resultData = db.collections.find().limit(limit).skip(skip) else: def findAllData(self, query, sortQuery): # 查询数据 print(self.dbname + "----" + self.collection) resultData = db.collections.find(query).sort(sortQuery) return resultData |
调用:
1 2 3 | print(dao.findAll(limit=2, skip=1)) print(dao.findAll(query={"x": "55"})) print(dao.findAll(query={"x": "55"}, sortQuery={"x": "55"})) |
报错:
Traceback (most recent call last):
File “DaoUtil.py”, line 84, in
print([item for item in dao.findAll(limit=2, skip=1)])
TypeError: ‘NoneType’ object is not iterable
写这段程序的时候,参照了网上一个例子,但是忽略了一个重要的部分{也是最重要的部分}.所以就报错了.
修改后的程序
下面的程序是最新的,可以运行的!
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 | """ 查询数据 """ def findAll(self, **kwargs): # print(kwargs) if self.dbname: collections = self.collection db = self.getDB() def findPage(self, dataLimit=None, dataSkip=None): # 分页查询数据 if dataLimit and isinstance(dataLimit, int): # limit 最多只显示多少. return db.collections.find().limit(dataLimit) if dataSkip and isinstance(dataSkip, int): # 跳过多少条 return db.collections.find().limit(10).skip(dataSkip) if isinstance(dataLimit, int) and isinstance(dataSkip, int): return db.collections.find().limit(dataLimit).skip(dataSkip) def findAllData(self, dataQuery=None, dataSortQuery=None): # 查询数据 if dataQuery: return db.collections.find(dataQuery) else: return db.collections.find() if dataSortQuery: return db.collections.find().sort(dataSortQuery) if dataQuery and dataSortQuery: return db.collections.find(dataQuery).sort(dataSortQuery) if len(kwargs) == 2: limit = kwargs.get('dataLimit', "") skip = kwargs.get('dataSkip', "") query = kwargs.get('dataQuery', "") sortQuery = kwargs.get('dataSortQuery', "") if limit or skip: return findPage(self, **kwargs) elif query or sortQuery: return findAllData(self, **kwargs) else: return findAllData(self, "", "") |
调用如下：
1 2 3 4 5 6 7 | print([item for item in dao.findAll()]) print([item for item in dao.findAll(dataLimit=2, dataSkip=1)]) print([item for item in dao.findAll( dataSkip=1)]) print([item for item in dao.findAll(dataLimit=2)]) print([item for item in dao.findAll(dataQuery={"x": "55"})]) print([item for item in dao.findAll(dataSortQuery=[("x", "55")])]) print([item for item in dao.findAll(dataQuery={"x": "55"}, dataSortQuery=[("x", "55")])]) |
输出MongoDB里面的数据.
最重要,工具目前暂未完成,剩余部分暂时不发了.等写完了再发整个工具.(不会安装MongoDB?自己搜索下.)
PS:工具已经完整发布(地址).