Recycling gunicorn worker (#800)

* add recycling feature to gunicorn worker

* add unit tests

* add more unit tests, and remove redundant trigger_events call

* fixed up unit tests

* make flake8 happy

* address feedbacks

* make flake8 happy

* add doc

tests/test_worker.py

@@ -3,7 +3,11 @@ import json
 import shlex
 import subprocess
 import urllib.request
-
+from unittest import mock
+from sanic.worker import GunicornWorker
+from sanic.app import Sanic
+import asyncio
+import logging
 import pytest
 
 
@@ -20,3 +24,79 @@ def test_gunicorn_worker(gunicorn_worker):
     with urllib.request.urlopen('http://localhost:1337/') as f:
         res = json.loads(f.read(100).decode())
     assert res['test']
+
+
+class GunicornTestWorker(GunicornWorker):
+
+    def __init__(self):
+        self.app = mock.Mock()
+        self.app.callable = Sanic("test_gunicorn_worker")
+        self.servers = {}
+        self.exit_code = 0
+        self.cfg = mock.Mock()
+        self.notify = mock.Mock()
+
+
+@pytest.fixture
+def worker():
+    return GunicornTestWorker()
+
+
+def test_worker_init_process(worker):
+    with mock.patch('sanic.worker.asyncio') as mock_asyncio:
+        try:
+            worker.init_process()
+        except TypeError:
+            pass
+
+        assert mock_asyncio.get_event_loop.return_value.close.called
+        assert mock_asyncio.new_event_loop.called
+        assert mock_asyncio.set_event_loop.called
+
+
+def test_worker_init_signals(worker):
+    worker.loop = mock.Mock()
+    worker.init_signals()
+    assert worker.loop.add_signal_handler.called
+
+
+def test_handle_abort(worker):
+    with mock.patch('sanic.worker.sys') as mock_sys:
+        worker.handle_abort(object(), object())
+        assert not worker.alive
+        assert worker.exit_code == 1
+        mock_sys.exit.assert_called_with(1)
+
+
+def test_handle_quit(worker):
+    worker.handle_quit(object(), object())
+    assert not worker.alive
+    assert worker.exit_code == 0
+
+
+def test_run_max_requests_exceeded(worker):
+    loop = asyncio.new_event_loop()
+    worker.ppid = 1
+    worker.alive = True
+    sock = mock.Mock()
+    sock.cfg_addr = ('localhost', 8080)
+    worker.sockets = [sock]
+    worker.wsgi = mock.Mock()
+    worker.connections = set()
+    worker.log = mock.Mock()
+    worker.loop = loop
+    worker.servers = {
+        "server1": {"requests_count": 14},
+        "server2": {"requests_count": 15},
+    }
+    worker.max_requests = 10
+    worker._run = mock.Mock(wraps=asyncio.coroutine(lambda *a, **kw: None))
+
+    # exceeding request count
+    _runner = asyncio.ensure_future(worker._check_alive(), loop=loop)
+    loop.run_until_complete(_runner)
+
+    assert worker.alive == False
+    worker.notify.assert_called_with()
+    worker.log.info.assert_called_with("Max requests exceeded, shutting down: %s",
+                                       worker)