[C4GT Community]: Raise NotImplementedError in InterfaceProtocolCheckMixin if either classes lack the declared method.

[codecakes]

Ticket Contents

Description

InterfaceProtocolCheckMixin checks for correct signature used by the implementation class. You can drop in the mixin wherever an implementation is subclassed with an interface definition.

For instance, a service interface is defined here
And It's implementation is here

InterfaceProtocolCheckMixin however doesn't exactly check if both the implementation and interface have the declared method.

Goals

Goals

• Raise NotImplementedError in InterfaceProtocolCheckMixin if both the implementation and interface do not have the declared method.
• Implement test cases.

Expected Outcome

During runtime:

1. Implementing an interface with InterfaceProtocolCheckMixin that lacks a method defined in interface will raise NotImplementedError.
2. Implementing an interface with InterfaceProtocolCheckMixin that has a method defined in interface but not in the implementation will raise NotImplementedError.

Acceptance Criteria

• Test checks for an stub implementation and a test interface for it and both have the methods.
• Test checks for an stub implementation and a test interface and raises NotImplementedError if either of them lack the method declaration.

Implementation Details

Check if both classes have the method declared here:

project-healthcare/xcov19/utils/mixins.py

Line 18 in 9648615

cls_method = getattr(parent_class, defined_method)

UPDATE
If you have an Interface class BaseClass and an implementation class IncorrectImplementation :

class BaseClass:
    def method_with_params(self, param1: int, param2: str):
        pass


class IncorrectImplementation(BaseClass, InterfaceProtocolCheckMixin):
    def method2(self, param1: int):
        pass

Then, Running IncorrectImplementation should raise NotImplementedError because method method_with_params is missing from IncorrectImplementation and method2 is not defined in the Interface BaseClass

Mockups/Wireframes

No response

Product Name

project-healthcare

Organisation Name

XCoV19

Domain

Healthcare

Tech Skills Needed

Debugging, Python, Test, Testing Library

Mentor(s)

@codecakes

Complexity

Low

Category

Backend, Beginner Friendly, Testing

[Blacksujit]

@codecakes can you please assign this to me i am interested in working on this issue

[MAVRICK-1]

@codecakes can you assign me this one

[codecakes]

@codecakes can you please assign this to me i am interested in working on this issue

@Blacksujit feel free to raise the PR. it will be automatically assigned to whoever has a PR in review.

[codecakes]

@codecakes can you assign me this one

@MAVRICK-1 feel free to raise the PR. it will be automatically assigned to whoever has a PR in review.

[RISHIKESHk07]

@codecakes was giving this a try but got stuck in pytests for this , any guide i could follow , i tested it on already implemented check for params not matching but it shows no error raised (i am on "main" branch )

[codecakes]

@codecakes was giving this a try but got stuck in pytests for this , any guide i could follow , i tested it on already implemented check for params not matching but it shows no error raised (i am on "main" branch )

@RISHIKESHk07 share instructions on what steps you took to reproduce your issue including command, code and screenshot.

[RISHIKESHk07]

@codecakes wrote a new test file and tested it , on main branch

[codecakes]

@codecakes wrote a new test file and tested it , on main branch

@RISHIKESHk07 Good effort to begin with but you are proving the point that you have already declared the method. You are not doing anything wrong but contradicting the issue this ticket asks to implement. The issue clearly states to check if the method, in your case method_with_params, is absent in either classes, then it should raise.

In your particular case, if you run this:

class BaseClass:
    def method_with_params(self, param1: int, param2: str):
        pass


class IncorrectImplementation(BaseClass, InterfaceProtocolCheckMixin):
    def method_with_params(self, param1: int):
        pass

IncorrectImplementation()

you will get a traceback like this because a.) you already have declared the method BUT b.) It has different signature.

Traceback (most recent call last):
    ...
    raise NotImplementedError(f"""Signature for {defined_method} not correct:
NotImplementedError: Signature for method_with_params not correct:
                Expected: ['self', 'param1', 'param2']
                Got: ['self', 'param1']

I suggest to read the description and goals again.

Additionally, when sharing a bug with a screenshot that you want others to try which has a reproducible code, share the code separately when sharing an issue on any ticket. I suggest to look at the following to understand what details to share as a helpful guide:

[RISHIKESHk07]

@codecakes Thanks for suggestions , i was not able get pytest working as shown in the terminal of photo ( figured it out after some trial and error ) . Will try to move forward in the issue

[codecakes]

@codecakes Thanks for suggestions , i was not able get pytest working as shown in the terminal of photo ( figured it out after some trial and error ) . Will try to move forward in the issue

@RISHIKESHk07 There is nothing wrong with your pytest setup. It is working and that is why it fails.

See contributing to understand how to run tests generally.

[codecakes]

@codecakes Thanks for suggestions , i was not able get pytest working as shown in the terminal of photo ( figured it out after some trial and error ) . Will try to move forward in the issue

@RISHIKESHk07 Check updated Implementation details section for clarity

[RISHIKESHk07]

@codecakes this is what i came up with , any suggestion i could make it better

[codecakes]

@RISHIKESHk07 I am unable to understand the context properly.
I suggest you follow the guidelines provided here when sharing an issue. See here and If you get stuck to understand how to share an issue and your findings. See what happens when standards are not followed. This is what I see when I click on your screeshot:

From whatever I can gather from your screenshot, once you have implemented the code and written a unit test for it, raise a PR

@codecakes this is what i came up with , any suggestion i could make it better