A minimal example for dogpile.cache in pyramid

dogpile_minimal.py

import logging
import random

from dogpile.cache import make_region
from pyramid.config import Configurator


logger = logging.getLogger(__name__)
region = make_region()


def cache_init(settings: dict):
    region.configure_from_config(
        {
            "cache.redis.backend": "dogpile.cache.redis",
            **settings,
        },
        "cache.redis.",
    )


@region.cache_on_arguments()
def count_up(i):
    print(i)
    return i + random.randint(1, 10)


def hello(request):
    first = count_up(1)
    second = count_up(1)
    count_up.invalidate(1)
    third = count_up(1)
    another = count_up(2)
    return {"first": first, "second": second, "third": third, "another": another}


def main(global_conf, **settings):
    config = Configurator(settings=settings)
    config.add_route("hello", "/hello")
    config.add_view(hello, route_name="hello", renderer="json")
    cache_init(settings)
    return config.make_wsgi_app()


if __name__ == "__main__":
    import waitress

    waitress.serve(main({}), host="0.0.0.0", port=9999)

with_class.py

import random

from dogpile.cache import make_region
from pyramid.config import Configurator


logger = logging.getLogger(__name__)
region = make_region()


def cache_init(settings: dict):
    region.configure_from_config(
        {
            "cache.redis.backend": "dogpile.cache.redis",
            **settings,
        },
        "cache.redis.",
    )


class MyClass:  # actually, use zope.interface
    def __init__(self) -> None:
        pass

    @region.cache_on_arguments(namespace="foo")
    def count_up(self, i):
        print(i)
        return i + random.randint(1, 10)


def hello(request):
    first = MyClass().count_up(1)
    second = MyClass().count_up(1)
    MyClass().count_up.invalidate(1)
    third = MyClass().count_up(1)
    another = MyClass().count_up(2)
    return {"first": first, "second": second, "third": third, "another": another}


def main(global_conf, **settings):
    config = Configurator(settings=settings)
    config.add_route("hello", "/hello")
    config.add_view(hello, route_name="hello", renderer="json")
    cache_init(settings)
    return config.make_wsgi_app()


if __name__ == "__main__":
    import waitress

    waitress.serve(main({}), host="0.0.0.0", port=9999)

Requirements:

pyramid
dogpile.cache

How to run:

docker run -d --rm -p 6379 redis
python dogpile_minimal.py

Behaviors

Expected (works on dogpile_minimal.py)

First access: {"first": x, "second": x, "third": y, "another": a}
Second: {"first": y, "second": y, "third": z, "another": a}
(a, x, y, z are integers)

Actually, in with_class.py

Always {"first": x, "second": x, "third": x, "another": a}

Why didn't work invalidation?

ref: Doc for Region.cache_on_arguments https://dogpilecache.sqlalchemy.org/en/latest/api.html#dogpile.cache.region.CacheRegion.cache_on_arguments

Here is a work-around for me.

def hello(request):
    first = MyClass().count_up(1)
    second = MyClass().count_up(1)
    MyClass().count_up.invalidate(None, 1)
    third = MyClass().count_up(1)
    another = MyClass().count_up(2)
    return {"first": first, "second": second, "third": third, "another": another}