Python: Allow methods that are not specifically defined are called ala __getattr__

I am trying to write a Python class capable of doing the following:

c = MyClass()
a = c.A("a name for A") # Calls internally c.create("A", "a name for A")
b = c.B("a name for B") # Calls internally c.create("B", "a name for B")

A and B can be any (well, they are defined in the database, but I do not want to explicitly define them in my code)

A hacky workaround for him would be to do the following:

class MyClass():
    def __init__(self):
        self.createItem = ""

    def create(self, itemType, itemName):
        print "Creating item %s with name %s" % (itemType, itemName)

    def create_wrapper(self, name):
        self.create(self.createItem, name)

    def __getattr__(self, attrName):
        self.createItem = attrName
        return self.create_wrapper

This will work when the user calls something like:

a = c.A("nameA")
b = c.B("nameB")

However, it will fall in situations where function pointers are stored without calling:

aFunc = c.A
bFunc = c.B
aFunc("nameA") # Is actually calling c.create("B", "nameA"),
               # as c.B was the last __getattr__() call
bFunc("nameB")

Any suggestions for something I don't see here?

thank

Edit: I seem to have just figured this out, but Philip has a much more elegant solution ....

My solution was:

class MyClassCreator():
    def __init__(self, origClass, itemType):
        self.origClass = origClass
        self.itemType = itemType

    def create_wrapper(self, name):
        return self.origClass.create(self.itemType, name)

class MyClass():
    def __init__(self):
        self.createItem = ""

    def create(self, itemType, itemName):
        print "Creating item %s with name %s" % (itemType, itemName)

    def __getattr__(self, attrName):
        return MyClassCreator(self, attrName).create_wrapper

In the version I actually used (since I needed a more difficult task than one argument): (I don’t know if this can be done using the lambda function ...)

def __getattr__(self, attrName):
    def find_entity_wrapper(*args, **kwargs):
        return self.find_entity(attrName, *args, **kwargs)

    return find_entity_wrapper
+3
2

__getattr__ :

class MyClass(object):
    def create(self, itemType, itemName):
        print "Creating item %s with name %s" % (itemType, itemName)

    def __getattr__(self, attrName):
        def create_wrapper(name):
            self.create(attrName, name)
        return create_wrapper

. - functools.partial:

import functools

class MyClass(object):
    def create(self, itemType, itemName, *args, **kwargs):
        print "Creating item %s with name %s, args %r and kwargs %r" % (itemType, itemName, args, kwargs)

    def __getattr__(self, attrName):
        return functools.partial(self.create, attrName)

c = MyClass()
bFunc = c.B
bFunc("nameB", 1, 2, foo=3)

.

+6

, , :

class MyClass():

    def create(self, itemType, itemName):
        print "Creating item %s with name %s" % (itemType, itemName)

    def __getattr__(self, attrName):
        return lambda x: self.create(attrName, x)

c = MyClass()
a = c.A("nameA")
b = c.B("nameB")


af = c.A
bf = c.B
af("nameA")
bf("nameB")

:

Creating item A with name nameA
Creating item B with name nameB
Creating item A with name nameA
Creating item B with name nameB
+5

Source: https://habr.com/ru/post/1758615/


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