From 4c5f14d3d95387d7e90de8f6ec097194b0a042a4 Mon Sep 17 00:00:00 2001
From: Ralph Bean <rbean@redhat.com>
Date: Sep 25 2017 16:54:37 +0000
Subject: Fix caching to be testable.


The old way didn't work because our ``cache`` object was global.  It
would get configured by the first test and then never be reconfigurable
for other tests.

This gets fixed here by hanging the cache region on `flask.current_app`
so that it gets reinstantiated and reconfigured for each test run (and
each WSGI process).

---

diff --git a/greenwave/app_factory.py b/greenwave/app_factory.py
index cb86e47..44b53a4 100644
--- a/greenwave/app_factory.py
+++ b/greenwave/app_factory.py
@@ -4,9 +4,9 @@
 from flask import Flask
 from greenwave.logger import init_logging
 from greenwave.api_v1 import api
-from greenwave.cache import cache
 from greenwave.utils import json_error, load_config
 
+from dogpile.cache import make_region
 from requests import ConnectionError, Timeout
 from werkzeug.exceptions import default_exceptions
 
@@ -32,8 +32,8 @@ def create_app(config_obj=None):
     app.add_url_rule('/healthcheck', view_func=healthcheck)
 
     # Initialize the cache.
-    if not cache.is_configured:
-        cache.configure(**app.config['CACHE'])
+    app.cache = make_region()
+    app.cache.configure(**app.config['CACHE'])
 
     return app
 
diff --git a/greenwave/cache.py b/greenwave/cache.py
index 27fb3b6..00bcf50 100644
--- a/greenwave/cache.py
+++ b/greenwave/cache.py
@@ -1,9 +1,19 @@
 # SPDX-License-Identifier: GPL-2.0+
 
 import dogpile.cache
-
-# Our globally available cache region.  Gets initialized in app_factory.
-cache = dogpile.cache.make_region()
+import flask
 
 # Provide a convenient alias for the key generator we want to use
 key_generator = dogpile.cache.util.function_key_generator
+
+
+def cached(fn):
+    """ Cache arguments with a region hung on the flask app. """
+    def wrapper(*args):
+        decoration = flask.current_app.cache.cache_on_arguments
+        decorator = decoration(function_key_generator=key_generator)
+        return decorator(fn)(*args)
+    wrapper.__name__ = fn.__name__
+    wrapper.__module__ = fn.__module__
+    wrapper.__doc__ = fn.__doc__
+    return wrapper
diff --git a/greenwave/resources.py b/greenwave/resources.py
index 2a95f2f..11335f0 100644
--- a/greenwave/resources.py
+++ b/greenwave/resources.py
@@ -9,12 +9,12 @@ waiverdb, etc..).
 import requests
 from flask import current_app
 
-from greenwave.cache import cache, key_generator
+from greenwave.cache import cached
 
 requests_session = requests.Session()
 
 
-@cache.cache_on_arguments(function_key_generator=key_generator)
+@cached
 def retrieve_results(item):
     """ Retrieve cached results from resultsdb for a given item. """
     # XXX make this more efficient than just fetching everything