Use more up-to-date memcached package (release-engineering#60)

python-memcached has not beed updated in many years and we now see the
following error appear everywhere in the logs
(linsomniac/python-memcached#176):

    /venv/lib64/python3.9/site-packages/memcache.py:1304: SyntaxWarning: "is" with a literal. Did you mean "=="?
      if key_extra_len is 0:

docker-compose.yml

@@ -92,6 +92,8 @@ services:
 
   memcached:
     image: "quay.io/factory2/memcached"
+    ports:
+      - 11211:11211
 
   resultsdb-listener:
     image: greenwave

docker/greenwave-settings.py

@@ -17,8 +17,8 @@
     "reconnect_attempts_max": 5,
 }
 CACHE = {
-    # 'backend': "dogpile.cache.null",
-    'backend': "dogpile.cache.memcached",
+    # 'backend': 'dogpile.cache.null',
+    'backend': 'dogpile.cache.pymemcache',
     'expiration_time': 1,  # 1 is 1 second, keep to see that memcached
                            # service is working
     'arguments': {

functional-tests/conftest.py

@@ -196,7 +196,7 @@ def cache_config(tmpdir_factory):
     if 'GREENWAVE_TEST_URL' in os.environ:
         # This should point to the same cache as the Greenwave server used by tests.
         return {
-            'backend': "dogpile.cache.memcached",
+            'backend': 'dogpile.cache.pymemcache',
             'expiration_time': 300,
             'arguments': {
                 'url': 'memcached:11211',

functional-tests/test_cache.py

@@ -0,0 +1,21 @@
+import uuid
+
+from dogpile.cache import make_region
+
+from greenwave.utils import sha1_mangle_key
+
+
+def test_cache():
+    cache = make_region(key_mangler=sha1_mangle_key)
+    cache.configure(
+        backend='dogpile.cache.pymemcache',
+        expiration_time=5,
+        arguments={
+            'url': 'localhost:11211',
+            'distributed_lock': True,
+        },
+    )
+    key = uuid.uuid1().hex
+    assert cache.get(key) is not True
+    cache.set(key, True)
+    assert cache.get(key) is True

openshift/greenwave-test-template.yaml

@@ -103,8 +103,8 @@ objects:
       WAIVERDB_API_URL = 'http://waiverdb-test-${TEST_ID}-web:8080/api/v1.0'
       RESULTSDB_API_URL = 'http://resultsdb-test-${TEST_ID}-internal-api:5001/api/v2.0'
       CACHE = {
-          #'backend': "dogpile.cache.null",
-          'backend': "dogpile.cache.memcached",
+          #'backend': 'dogpile.cache.null',
+          'backend': 'dogpile.cache.pymemcache',
           'expiration_time': 1, # 1 is 1 second, keep to see that memcached
                                 # service is working
           'arguments': {

pyproject.toml

@@ -27,7 +27,6 @@ PyYAML = "^6.0"
 "dogpile.cache" = "^1.1.4"
 flask = "^2.1.2"
 gunicorn = "^20.1.0"
-python-memcached = "^1.59"
 requests = "^2.28.1"
 python-dateutil = "^2.8.2"
 fedora-messaging = "^2.1.0"
@@ -46,6 +45,7 @@ psycopg2-binary = {version = "^2.9.3", optional = true}
 sphinx = {version = "^5.0.2", optional = true}
 sphinxcontrib-httpdomain = {version = "^1.8.0", optional = true}
 statsd = "^3.3.0"
+pymemcache = "^3.5.2"
 
 [tool.poetry.extras]
 test = [