fix(regression-tests): Add PortPicker (#1078)

* fix(regression-tests): Add PortManager

Add PortManager to find and use available ports in regression tests.
Use it in redis_replicaiton_test.
---------

Signed-off-by: ashotland <ari@dragonflydb.io>

tests/dragonfly/__init__.py

@@ -139,3 +139,20 @@ def dfly_args(*args):
 def dfly_multi_test_args(*args):
     """ Used to define multiple sets of arguments to test multiple dragonfly configurations """
     return pytest.mark.parametrize("df_factory", args, indirect=True)
+
+
+class PortPicker():
+    """ A simple port manager to allocate available ports for tests """
+
+    def __init__(self):
+        self.next_port = 5555
+
+    def get_available_port(self):
+        while not self.is_port_available(self.next_port):
+            self.next_port += 1
+        return self.next_port
+
+    def is_port_available(self, port):
+        import socket
+        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+            return s.connect_ex(('localhost', port)) != 0

tests/dragonfly/conftest.py

@@ -14,7 +14,7 @@ import random
 from pathlib import Path
 from tempfile import TemporaryDirectory
 
-from . import DflyInstance, DflyInstanceFactory, DflyParams
+from . import DflyInstance, DflyInstanceFactory, DflyParams, PortPicker
 from .utility import DflySeederFactory
 
 DATABASE_INDEX = 1
@@ -188,3 +188,8 @@ def pytest_addoption(parser):
     )
     parser.addoption(
         '--existing-port', action='store', default=None, help='Provide a port to the existing process for the test')
+
+
+@pytest.fixture(scope="session")
+def port_picker():
+    yield PortPicker()

tests/dragonfly/redis_replicaiton_test.py

@@ -7,8 +7,8 @@ from .utility import *
 
 
 class RedisServer:
-    def __init__(self):
-        self.port = 5555
+    def __init__(self, port):
+        self.port = port
         self.proc = None
 
     def start(self):
@@ -66,8 +66,8 @@ async def check_data(seeder, replicas, c_replicas):
 
 
 @pytest.fixture(scope="function")
-def redis_server() -> RedisServer:
-    s = RedisServer()
+def redis_server(port_picker) -> RedisServer:
+    s = RedisServer(port_picker.get_available_port())
     try:
         s.start()
     except FileNotFoundError as e:
@@ -86,7 +86,7 @@ full_sync_replication_specs = [
 
 
 @pytest.mark.parametrize("t_replicas, seeder_config", full_sync_replication_specs)
-async def test_replication_full_sync(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config):
+async def test_replication_full_sync(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config, port_picker):
     master = redis_server
     c_master = aioredis.Redis(port=master.port)
     assert await c_master.ping()
@@ -95,7 +95,7 @@ async def test_replication_full_sync(df_local_factory, df_seeder_factory, redis_
     await seeder.run(target_deviation=0.1)
 
     replica = df_local_factory.create(
-        port=master.port + 1, proactor_threads=t_replicas[0])
+        port=port_picker.get_available_port(), proactor_threads=t_replicas[0])
     replica.start()
     c_replica = aioredis.Redis(port=replica.port)
     assert await c_replica.ping()
@@ -117,13 +117,13 @@ stable_sync_replication_specs = [
 
 
 @pytest.mark.parametrize("t_replicas, seeder_config", stable_sync_replication_specs)
-async def test_replication_stable_sync(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config):
+async def test_replication_stable_sync(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config, port_picker):
     master = redis_server
     c_master = aioredis.Redis(port=master.port)
     assert await c_master.ping()
 
     replica = df_local_factory.create(
-        port=master.port + 1, proactor_threads=t_replicas[0])
+        port=port_picker.get_available_port(), proactor_threads=t_replicas[0])
     replica.start()
     c_replica = aioredis.Redis(port=replica.port)
     assert await c_replica.ping()
@@ -152,13 +152,13 @@ replication_specs = [
 
 
 @pytest.mark.parametrize("t_replicas, seeder_config", replication_specs)
-async def test_redis_replication_all(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config):
+async def test_redis_replication_all(df_local_factory, df_seeder_factory, redis_server, t_replicas, seeder_config, port_picker):
     master = redis_server
     c_master = aioredis.Redis(port=master.port)
     assert await c_master.ping()
 
     replicas = [
-        df_local_factory.create(port=master.port+i+1, proactor_threads=t)
+        df_local_factory.create(port=port_picker.get_available_port(), proactor_threads=t)
         for i, t in enumerate(t_replicas)
     ]
 
@@ -208,14 +208,13 @@ master_disconnect_cases = [
 
 
 @pytest.mark.parametrize("t_replicas, t_disconnect, seeder_config", master_disconnect_cases)
-async def test_disconnect_master(df_local_factory, df_seeder_factory, redis_server, t_replicas, t_disconnect, seeder_config):
-
+async def test_disconnect_master(df_local_factory, df_seeder_factory, redis_server, t_replicas, t_disconnect, seeder_config, port_picker):
     master = redis_server
     c_master = aioredis.Redis(port=master.port)
     assert await c_master.ping()
 
     replicas = [
-        df_local_factory.create(port=master.port+i+1, proactor_threads=t)
+        df_local_factory.create(port=port_picker.get_available_port(), proactor_threads=t)
         for i, t in enumerate(t_replicas)
     ]