redis-py 3

.circleci/config.yml

@@ -4,25 +4,34 @@ workflows:
   version: 2
   workflow:
     jobs:
-      - test-2.7
-      - test-3.5
+      - test-3.6
+      - test-3.7
+      - test-3.8
 
 defaults: &defaults
   working_directory: ~/code
   steps:
   - checkout
+  - run:
+      name: Install dependencies
+      command: pip install --user -r requirements.txt
   - run:
       name: Test
-      command: python setup.py test
+      command: pytest tests.py
 
 jobs:
-  test-2.7:
+  test-3.6:
+    <<: *defaults
+    docker:
+    - image: circleci/python:3.6
+    - image: redis:6.2.0
+  test-3.7:
     <<: *defaults
     docker:
-    - image: circleci/python:2.7
-    - image: redis:3
-  test-3.5:
+    - image: circleci/python:3.7
+    - image: redis:6.2.0
+  test-3.8:
     <<: *defaults
     docker:
-    - image: circleci/python:3.5
-    - image: redis:3
+    - image: circleci/python:3.8
+    - image: redis:6.2.0

redis_hashring/__init__.py

@@ -11,7 +11,7 @@
 
 # Amount of points on the ring. Must not be higher than 2**32 because we're
 # using CRC32 to compute the checksum.
-RING_SIZE = 2**32
+RING_SIZE = 2 ** 32
 
 # Default amount of replicas per node
 RING_REPLICAS = 16
@@ -70,14 +70,15 @@ def __init__(self, conn, key, n_replicas=RING_REPLICAS):
         host = socket.gethostname()
         pid = os.getpid()
         # Create unique identifiers for the replicas
-        self.replicas = [(
-            random.randrange(2**32),
-            '{host}:{pid}:{rand}'.format(
-                host=host,
-                pid=pid,
-                rand=binascii.hexlify(os.urandom(4)).decode()
+        self.replicas = [
+            (
+                random.randrange(2 ** 32),
+                '{host}:{pid}:{rand}'.format(
+                    host=host, pid=pid, rand=binascii.hexlify(os.urandom(4)).decode()
+                ),
             )
-        ) for n in range(n_replicas)]
+            for n in range(n_replicas)
+        ]
 
         # List of tuples of ranges this node is responsible for, where a tuple
         # (a, b) includes any N matching a <= N < b.
@@ -154,44 +155,52 @@ def debug_print(self):
             hostname, pid, rnd = replica.split(':')
             node = ':'.join([hostname, pid])
 
-            abs_size = (ring[(n+1) % n_replicas][0] - ring[n][0]) % RING_SIZE
-            size = 100. / RING_SIZE * abs_size
+            abs_size = (ring[(n + 1) % n_replicas][0] - ring[n][0]) % RING_SIZE
+            size = 100.0 / RING_SIZE * abs_size
             delay = int(now - heartbeat)
 
             nodes[node].append((hostname, pid, abs_size, delay, expired))
 
-            print('{start:10} {size:5.2f}% {delay:6}s {replica}{extra}'.format(
-                start=start,
-                replica=replica,
-                delay=delay,
-                size=size,
-                extra=' (EXPIRED)' if expired else ''
-            ))
+            print(
+                '{start:10} {size:5.2f}% {delay:6}s {replica}{extra}'.format(
+                    start=start,
+                    replica=replica,
+                    delay=delay,
+                    size=size,
+                    extra=' (EXPIRED)' if expired else '',
+                )
+            )
 
         print()
         print('Hash ring "{key}" nodes:'.format(key=self.key))
 
         if nodes:
-            print('{:8} {:8} {:7} {:20} {:5}'.format('Range', 'Replicas', 'Delay', 'Hostname', 'PID'))
+            print(
+                '{:8} {:8} {:7} {:20} {:5}'.format(
+                    'Range', 'Replicas', 'Delay', 'Hostname', 'PID'
+                )
+            )
         else:
             print('(no nodes)')
 
         for k, v in nodes.items():
             hostname, pid = v[0][0], v[0][1]
             abs_size = sum(replica[2] for replica in v)
-            size = 100. / RING_SIZE * abs_size
+            size = 100.0 / RING_SIZE * abs_size
             delay = max(replica[3] for replica in v)
             expired = any(replica[4] for replica in v)
             count = len(v)
-            print('{size:5.2f}% {count:8} {delay:6}s {hostname:20} {pid:5}{extra}'.format(
-                start=start,
-                count=count,
-                hostname=hostname,
-                pid=pid,
-                delay=delay,
-                size=size,
-                extra=' (EXPIRED)' if expired else ''
-            ))
+            print(
+                '{size:5.2f}% {count:8} {delay:6}s {hostname:20} {pid:5}{extra}'.format(
+                    start=start,
+                    count=count,
+                    hostname=hostname,
+                    pid=pid,
+                    delay=delay,
+                    size=size,
+                    extra=' (EXPIRED)' if expired else '',
+                )
+            )
 
     def heartbeat(self):
         """
@@ -201,10 +210,12 @@ def heartbeat(self):
         pipeline = self.conn.pipeline()
         now = time.time()
         for replica in self.replicas:
-            pipeline.zadd(self.key, '{start}:{name}'.format(
-                start=replica[0],
-                name=replica[1]
-            ), now)
+            pipeline.zadd(
+                self.key,
+                {
+                    '{start}:{name}'.format(start=replica[0], name=replica[1]): now,
+                },
+            )
         ret = pipeline.execute()
 
         # Only notify the other nodes if we're not in the ring yet.
@@ -217,10 +228,9 @@ def remove(self):
         """
         pipeline = self.conn.pipeline()
         for replica in self.replicas:
-            pipeline.zrem(self.key, '{start}:{name}'.format(
-                start=replica[0],
-                name=replica[1]
-            ))
+            pipeline.zrem(
+                self.key, '{start}:{name}'.format(start=replica[0], name=replica[1])
+            )
         pipeline.execute()
         self._notify()
 
@@ -251,7 +261,7 @@ def update(self):
         self.ranges = []
         for n, (start, replica) in enumerate(ring):
             if replica in replica_set:
-                end = ring[(n+1) % n_replicas][0] % RING_SIZE
+                end = ring[(n + 1) % n_replicas][0] % RING_SIZE
                 if start < end:
                     self.ranges.append((start, end))
                 elif end < start:
@@ -330,6 +340,7 @@ def gevent_start(self):
         """
         import gevent
         import gevent.select
+
         self._poller_greenlet = gevent.spawn(self.poll)
         self._select = gevent.select.select
         self.heartbeat()
@@ -340,6 +351,7 @@ def gevent_stop(self):
         Helper method to stop the node for gevent-based applications.
         """
         import gevent
+
         gevent.kill(self._poller_greenlet)
         self.remove()
         self._select = select.select

requirements.txt

@@ -0,0 +1,2 @@
+redis==3.5.3
+pytest==6.2.2

setup.py

@@ -2,23 +2,27 @@
 
 setup(
     name='redis-hashring',
-    version='0.1.3',
+    version='0.2.0',
+    author='Close Engineering',
+    author_email='engineering@close.com',
     url='http://github.com/closeio/redis-hashring',
     license='MIT',
-    description='Python library for distributed applications using a Redis hash ring',
-    test_suite='tests',
-    tests_require=['redis==2.10.6'],
+    description=(
+        'Python library for distributed applications using a Redis hash ring'
+    ),
+    install_requires=['redis>=3,<4'],
     platforms='any',
     classifiers=[
         'Intended Audience :: Developers',
         'License :: OSI Approved :: MIT License',
         'Operating System :: OS Independent',
         'Topic :: Software Development :: Libraries :: Python Modules',
         'Programming Language :: Python',
-        'Programming Language :: Python :: 2',
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3 :: Only',
+        'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
     ],
     packages=[
         'redis_hashring',

tests.py

@@ -1,39 +1,43 @@
+import pytest
 from redis import Redis
-import unittest
 from redis_hashring import RingNode
 
 TEST_KEY = 'hashring-test'
 
-class HashRingTestCase(unittest.TestCase):
-    def setUp(self):
-        self.redis = Redis()
-        self.redis.delete(TEST_KEY)
 
-    def get_node(self, n_replicas, total_replicas):
-        node = RingNode(self.redis, TEST_KEY, n_replicas=n_replicas)
+@pytest.fixture
+def redis():
+    redis = Redis()
+    yield redis
+    redis.delete(TEST_KEY)
 
-        self.assertEqual(len(node.replicas), n_replicas)
-        self.assertEqual(self.redis.zcard(TEST_KEY), total_replicas-n_replicas)
 
-        node.heartbeat()
+def get_node(redis, n_replicas, total_replicas):
+    node = RingNode(redis, TEST_KEY, n_replicas=n_replicas)
 
-        self.assertEqual(self.redis.zcard(TEST_KEY), total_replicas)
-        self.assertEqual(len(node.ranges), 0)
+    assert len(node.replicas) == n_replicas
+    assert redis.zcard(TEST_KEY) == total_replicas - n_replicas
 
-        return node
+    node.heartbeat()
 
-    def test_node(self):
-        node1 = self.get_node(1, 1)
-        node1.update()
-        self.assertEqual(len(node1.ranges), 1)
+    assert redis.zcard(TEST_KEY) == total_replicas
+    assert len(node.ranges) == 0
 
-        node2 = self.get_node(1, 2)
-        node1.update()
-        node2.update()
-        self.assertEqual(len(node1.ranges) + len(node2.ranges), 3)
+    return node
 
-        node3 = self.get_node(2, 4)
-        node1.update()
-        node2.update()
-        node3.update()
-        self.assertEqual(len(node1.ranges) + len(node2.ranges) + len(node3.ranges), 5)
+
+def test_node(redis):
+    node1 = get_node(redis, 1, 1)
+    node1.update()
+    assert len(node1.ranges) == 1
+
+    node2 = get_node(redis, 1, 2)
+    node1.update()
+    node2.update()
+    assert len(node1.ranges) + len(node2.ranges) == 3
+
+    node3 = get_node(redis, 2, 4)
+    node1.update()
+    node2.update()
+    node3.update()
+    assert len(node1.ranges) + len(node2.ranges) + len(node3.ranges) == 5