Merge pull request #58 from pytest-dev/55-reduce-live-server-start-time

Author: nicoddemus

docs/changelog.rst

@@ -3,6 +3,15 @@
 Changelog
 =========
 
+1.1.0 (UNRELEASED)
+------------------
+
+- Speedup live server start time. Use `socket` instead of server
+  pulling (`#58`_) to check server availability and add new
+  ``--live-server-wait`` option to set the live server wait timeout.
+  Thanks to `@jadkik`_.
+
+
 1.0.0 (2020-03-03)
 ------------------
 
@@ -104,7 +113,9 @@ Changelog
 .. _#48: https://github.com/pytest-dev/pytest-flask/pull/48
 .. _#50: https://github.com/pytest-dev/pytest-flask/pull/50
 .. _#56: https://github.com/pytest-dev/pytest-flask/pull/56
+.. _#58: steenzouthttps://github.com/pytest-dev/pytest-flask/pull/58
 .. _@danstender: https://github.com/danstender
+.. _@jadkik: https://github.com/jadkik
 .. _@jineshpaloor: https://github.com/jineshpaloor
 .. _@mattwbarry: https://github.com/mattwbarry
 .. _@steenzout: https://github.com/steenzout

docs/features.rst

@@ -174,6 +174,10 @@ example, in your project’s ``pytest.ini`` file)::
             assert b'got it' in res.read()
 
 
+``--live-server-wait`` - the live server wait timeout (5 seconds)
+`````````````````````````````````````````````````````````````````
+
+The timeout after which test case is aborted if live server is not started.
 ``--live-server-port`` - use a fixed port
 `````````````````````````````````````````
 

pytest_flask/fixtures.py

@@ -1,17 +1,35 @@
 #!/usr/bin/env python
+import functools
 import logging
 import multiprocessing
 import os
 import signal
 import socket
 import time
-from urllib.error import URLError
-from urllib.request import urlopen
+import warnings
 
 import pytest
 from flask import _request_ctx_stack
 
 
+def deprecated(reason):
+    """Decorator which can be used to mark function or method as deprecated.
+    It will result a warning being emmitted when the function is called.
+    """
+
+    def decorator(func):
+        @functools.wraps(func)
+        def deprecated_call(*args, **kwargs):
+            warnings.simplefilter("always", DeprecationWarning)
+            warnings.warn(reason, DeprecationWarning, stacklevel=2)
+            warnings.simplefilter("default", DeprecationWarning)
+            return func(*args, **kwargs)
+
+        return deprecated_call
+
+    return decorator
+
+
 @pytest.yield_fixture
 def client(app):
     """A Flask test client. An instance of :class:`flask.testing.TestClient`
@@ -47,12 +65,15 @@ class LiveServer:
     :param app: The application to run.
     :param host: The host where to listen (default localhost).
     :param port: The port to run application.
+    :param wait: The timeout after which test case is aborted if
+                 application is not started.
     """
 
-    def __init__(self, app, host, port, clean_stop=False):
+    def __init__(self, app, host, port, wait, clean_stop=False):
         self.app = app
         self.port = port
         self.host = host
+        self.wait = wait
         self.clean_stop = clean_stop
         self._process = None
 
@@ -65,22 +86,45 @@ def worker(app, host, port):
         self._process = multiprocessing.Process(
             target=worker, args=(self.app, self.host, self.port)
         )
+        self._process.daemon = True
         self._process.start()
 
-        # We must wait for the server to start listening with a maximum
-        # timeout of 5 seconds.
-        timeout = 5
-        while timeout > 0:
-            time.sleep(1)
-            try:
-                urlopen(self.url())
-                timeout = 0
-            except URLError:
-                timeout -= 1
-
+        keep_trying = True
+        start_time = time.time()
+        while keep_trying:
+            elapsed_time = time.time() - start_time
+            if elapsed_time > self.wait:
+                pytest.fail(
+                    "Failed to start the server after {!s} "
+                    "seconds.".format(self.wait)
+                )
+            if self._is_ready():
+                keep_trying = False
+
+    def _is_ready(self):
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        try:
+            sock.connect((self.host, self.port))
+        except socket.error:
+            ret = False
+        else:
+            ret = True
+        finally:
+            sock.close()
+        return ret
+
+    @deprecated(
+        reason=(
+            'The "live_server.url" method is deprecated and will '
+            "be removed in the future. Please use "
+            'the "flask.url_for" function instead.',
+        )
+    )
     def url(self, url=""):
         """Returns the complete url based on server options."""
-        return "http://%s:%d%s" % (self.host, self.port, url)
+        return "http://{host!s}:{port!s}{url!s}".format(
+            host=self.host, port=self.port, url=url
+        )
 
     def stop(self):
         """Stop application process."""
@@ -155,8 +199,9 @@ def test_server_is_up_and_running(live_server):
     final_server_name = _rewrite_server_name(original_server_name, str(port))
     app.config["SERVER_NAME"] = final_server_name
 
+    wait = request.config.getvalue("live_server_wait")
     clean_stop = request.config.getvalue("live_server_clean_stop")
-    server = LiveServer(app, host, port, clean_stop)
+    server = LiveServer(app, host, port, wait, clean_stop)
     if request.config.getvalue("start_live_server"):
         server.start()
 

pytest_flask/plugin.py

@@ -165,6 +165,15 @@ def pytest_addoption(parser):
         dest="start_live_server",
         help="don't start server automatically when live_server " "fixture is applied.",
     )
+    group.addoption(
+        "--live-server-wait",
+        action="store",
+        dest="live_server_wait",
+        default=5,
+        type=float,
+        help="the timeout after which test case is aborted if live server is "
+        " not started.",
+    )
     group.addoption(
         "--live-server-clean-stop",
         action="store_true",

tests/test_live_server.py

@@ -10,6 +10,10 @@
 
 
 class TestLiveServer:
+    def test_init(self, live_server):
+        assert live_server.port
+        assert live_server.host == "localhost"
+
     def test_server_is_alive(self, live_server):
         assert live_server._process
         assert live_server._process.is_alive()
@@ -18,7 +22,12 @@ def test_server_url(self, live_server):
         assert live_server.url() == "http://localhost:%d" % live_server.port
         assert live_server.url("/ping") == "http://localhost:%d/ping" % live_server.port
 
+    def test_server_url_is_deprecated(self, live_server):
+        assert pytest.deprecated_call(live_server.url)
+
     def test_server_listening(self, live_server):
+        # need to test both external and external? why external here?
+        # res = urlopen(url_for('ping', _external=True))
         res = urlopen(live_server.url("/ping"))
         assert res.code == 200
         assert b"pong" in res.read()
@@ -207,3 +216,16 @@ def test_port(live_server):
         result = appdir.runpytest("-v", "--live-server-host", str(host))
         result.stdout.fnmatch_lines(["*PASSED*"])
         assert result.ret == 0
+
+    def test_respect_wait_timeout(self, appdir):
+        appdir.create_test_module(
+            """
+            import pytest
+
+            def test_should_fail(live_server):
+                assert live_server._process.is_alive()
+        """
+        )
+        result = appdir.runpytest("-v", "--live-server-wait=0.00000001")
+        result.stdout.fnmatch_lines(["**ERROR**"])
+        assert result.ret == 1