[Python] Flask cache memoize not working with flask restful resources

flask_cache.Cache.memoize not working with flask_restful.Resource

Here is sample code:

from flask import Flask, request, jsonify
from flask_restful import Resource, Api
from flask_cache import Cache

app = Flask(__name__)
api = Api(app)
cache = Cache(app, config={'CACHE_TYPE': 'simple'})


class MyResource(Resource):
JSONIFY = True
PATH = None
ENDPOINT = None

def dispatch_request(self, *args, **kwargs):
kw = dict(**kwargs)
kw.update(request.args.items())
r = super().dispatch_request(*args, **kw)
if self.JSONIFY:
return jsonify(r)
else:
return r


class DebugResource(MyResource):
PATH = '/debug'
ENDPOINT = 'debug'

@cache.memoize(timeout=30)
def get(self, **kwargs):
print('cache is not used!')
return kwargs

for r in [DebugResource]:
api.add_resource(r, r.PATH, endpoint=r.ENDPOINT)


print('running!')
app.run()


Notice that in get() I added print so I can see when the code is actually called and when cached value is used.

I start server then in browser i go to http://localhost:5000/debug?a=1 and press f5 repeatetely. I expect that my function get is called once and then cached value is used. But in server console I see my print each time I press f5. So memoize is not working. What am I doing wrong?

edit:

I moved my cached function outside from Resource class

@cache.memoize(timeout=30)
def my_foo(a):
print('cache is not used!')
return dict(kw=a, id=id(a))

class DebugResource(MyResource):
PATH = '/debug'
ENDPOINT = 'debug'

def get(self, a):
return my_foo(a)


and that worked. As far as I can see, the issue was self argument that was actually unique in each call. The question is still, how to make it work without extracting additional function for each method i want to cache? Current solution looks like a workaround.

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