How to inherit class in python (odoo framework controller)

Question

I've encountered an inheritance problem in Python. I'd expect the output from by program to be:

# url: home/animal
response: CLASS: Animal | Ability : none

---

# url: home/animal/bird
response: CLASS: Bird | Ability : Fly

---

# url: home/animal/fish
response: CLASS: Fish | Ability : Swim

But I get the following output:

# url: home/animal
response: CLASS: Fish | Ability : Swim

---

# url: home/animal/bird
response: CLASS: Fish | Ability : Swim

---

# url: home/animal/fish
response: CLASS: Fish | Ability : Swim

Here is my code:

class Animal(http.Controller):
    name = 'Animal'
    ability = 'none'

    @http.route('/animal', auth='public', type='http', website=True, csrf=False)
    def util(self, **kwargs):
        return self.message()

    def message(self):
        return "Name: "+self.name +" | Ability : " + self.ability

class Bird(Animal):
    name = 'Bird'
    ability = 'fly'

    @http.route('/animal/bird', auth='public', type='http', website=True, csrf=False)
    def util1(self, **kwargs):
        return self.message()


class Fish(Animal):
    name = 'Fish'
    ability = 'swim'

    @http.route('/animal/fish', auth='public', type='http', website=True, csrf=False)
    def util2(self, **kwargs):
        return self.message()

I've read quite a lot about inheritance, but still couldn't find a solution for this problem. Could it be because it has a different system in odoo python?

Edit: Here is the code that works, based on @Bruno's answer.

class Animal():
    name = 'Animal'
    ability = 'none'

    def message(self):
        return "Name: {self.name} | Ability : {self.ability} ".format(self=self)

class Bird(Animal):
    name = 'Bird'
    ability = 'fly'

class Fish(Animal):
    name = 'Fish'
    ability = 'swim'

class MyController(http.Controller):
    def __init__(self):
        self._animal = Animal()
        self._bird = Bird()
        self._fish = Fish()

    @http.route('/animal', auth='public', type='http', website=True, csrf=False)
    def animal(self, **kwargs):
        return self._animal.message()

    @http.route('/animal/bird', auth='public', type='http', website=True, csrf=False)
    def bird(self, **kwargs):
        return self._bird.message()

    @http.route('/animal/fish', auth='public', type='http', website=True, csrf=False)
    def fish(self, **kwargs):
        return self._fish.message()

Answer 1

Caveat: I never used odoo at all so this answer is partly wild guess based on what I could get from the doc and the behaviour you describe.

According to the doc, it looks like inheriting from a controller will actually override the original controller, not add a new one (nb cf the caveat above ok ?). If so, one thing you could try would be to use multiple inheritance instead, extracting your specific features to a non-controller base class:

class Animal(object):
    name = 'Animal'
    ability = 'none'

    def message(self):
        # using string formatting for improved readability
        return "Name: {self.name} | Ability : {self.ability}".format(self=self)


class Bird(Animal):
    name = "Bird"
    ability = Fly

# etc

class AnimalController(Animal, http.Controller):
    @http.route('/animal', auth='public', type='http', website=True, csrf=False)
    def util(self, **kwargs):
        return self.message()

class BirdController(Bird, http.Controller):
    @http.route('/animal/bird', auth='public', type='http', website=True, csrf=False)
    def util(self, **kwargs):
        return self.message()

but this doesn't really look like good design to me. A controller can typically handle many routes (this is the case for all MVC web frameworks, and since the route decorator is to be applied on methods I assume this works the same here), so it might be simpler to only keep one single controller and delegate to your Animal hierarchy:

class Animal(object):
    name = 'Animal'
    ability = 'none'

    def message(self):
        # using string formatting for improved readability
        return "Name: {self.name} | Ability : {self.ability}".format(self=self)


class Bird(Animal):
    name = "Bird"
    ability = Fly

# etc


class Controller(http.controller):
    def __init__(self, ...):
        self._animal = Animal()
        self._bird = Bird()
        # etc

    @http.route('/animal', auth='public', type='http', website=True, csrf=False)
    def animal(self, **kwargs):
        return self._animal.message()

    @http.route('/animal/bird', auth='public', type='http', website=True, csrf=False)
    def bird(self, **kwargs):
        return self._bird.message()

   # etc

This is of course incomplete example code so you get the general idea and will obviously need to be modified to match both odoo expectations and your project's needs.

Answer 2

Are you actually trying to inherit http.controller? If so, the default 0Auth module in Odoo can perhaps show you how that is arranged (since it also inherits this class).

If you are just trying to add a new class to Odoo, note that it has it's own inheritance system, which is described in the documentation (and works vastly different from default python): Odoo inheritance documentation for version 11.0

Note that although I have no personal experience with inheriting anything anything other than Odoo objects within Odoo, I found a lot of examples in the standard addons that should help you on your way.