I am writing some python gui app (PySide to be exact) and I am using my own class to handling DB. What's the correct way to use models? Currently I have something like this:
class DB(object):
def __init__(self, dbfile):
some db connect work
def updateEntry(entryid):
some update query etc
def getEntry(entryid):
fetching entry from db
def createEntry(entryvalue):
insert entry
class EntryModel(object):
def __init__(db,entryid=None,entryvalue=None):
self.db=db
self.entryid=entryid
self.entryvalue=entryvalue
if entryid is None:
self.db.createEntry(self.entryvalue)
elif self.entryvalue is None:
self.db.getEntry(self.entryid)
def some_func(self):
some other work
And it's working just fine... But I have a feeling that something is wrong here... I mean, I have to pass DB to each model, I don't think that's correct way. How to do it in proper way without using frameworks like SQLAlchemy and so on?
asked Jun 5, 2015 at 4:52
middleofdreams
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You could instantiate the db as a global variable (not sure if this is the right way to do it either, but it's how I tend to think of things)miriamsimone– miriamsimone2015年06月05日 05:12:38 +00:00Commented Jun 5, 2015 at 5:12
1 Answer 1
You can at least create a base class, let's called it Model (like in Django, or Base as it is called in SQLAlchemy)
We'll keep a reference to the db object as a class attribute so it is the same for all instances, and inherited so you don't have to pass it around
class Model(object):
db = None # This var is a class attribute
@classmethod
def init_db(cls):
cls.db = your_code_to_create_db()
class Entry(Model):
def __init__(self, entry_id, entry_value):
self.entry_id = entry_id
self.entry_value = entry_value
super(Entry, self).__init__()
def save(self):
# Use db here
self.db
# To use
Model.init_db() # Inits the one db var for the class
entry = Entry(...)
entry.save()
I hope you see the idea and adapt it to your needs!
answered Jun 5, 2015 at 5:21
bakkal
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1 Comment
middleofdreams
Great, it is something I was looking for, I completely forgot about class methods and attributes. Thanks!
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