Idiomatic way to to match against list of munch.munch objects?

Question

I am using the openstack shade library to manage our openstack stacks. One task is to list all stacks owned by a user (for example to then allow for deletion of them).

The shade library call list_stacks() returns a list of munch.Munch objects, and basically I want to identify that stack object that has either an 'id' or 'name' matching some user provided input.

I came up with this code here:

def __find_stack(self, connection, stack_info):
        stacks = connection.list_stacks()
        for stack in stacks:
            if stack_info in stack.values():
                return stack
        return None

But it feels clumsy, and I am wondering if there is a more idiomatic way to solve this in python? (stack_info is a simple string, either the "name" or "id", in other words: it might match this or that entry within the "dict" values of the munched stack objects)

Given the additional info, I don't see anything wrong or clumsy with this approach, and I don't see why anyone would consider this not idiomatic. If `stack_info` was a dictionary you could have probably used some `set` operations but that would probably be an overkill. Anyway, your way is perfectly acceptable IMHO. You could consider making it *shorter* with `map` but that would hurt readability. — DeepSpace, Dec 17 '18 at 12:02

score 2 · Accepted Answer · answered Dec 17 '18 at 12:12

As my comment suggests, I don't really think there is something to improve.

However, performance-wise, you could use filter to push the loop down to C level which may be beneficial if there are a lot of stacks.

Readability-wise, I don't think that you would gain much.

def __find_stack(self, connection, stack_info):
    stacks = connection.list_stacks()
    return list(filter(lambda stack: stack_info in stack.values(), stacks))

However this approach is not "short-circuited". Your original code stops when it finds a match, and this one will not, so in theory you will get more than one match if they exist (or an empty list in case there is no match).

Really nice and thoughtful! – GhostCat Dec 17 '18 at 12:37 — GhostCat, Dec 17 '18 at 12:37

Idiomatic way to to match against list of munch.munch objects?

1 Answers1