Merge pull request #36 from vitalk/optional-live-server-start

Add options to prevent live server from starting automatically.

Author: vitalk

docs/features.rst

@@ -139,6 +139,41 @@ other headless browsers).
             assert res.code == 200
 
 
+``--start-live-server`` - start live server automatically (default)
+```````````````````````````````````````````````````````````````````
+
+
+``--no-start-live-server`` - don't start live server automatically
+``````````````````````````````````````````````````````````````````
+
+By default the server is starting automatically whenever you reference
+``live_server`` fixture in your tests. But starting live server imposes some
+high costs on tests that need it when they may not be ready yet. To prevent
+that behaviour pass ``--no-start-live-server`` into your default options (for
+example, in your project's ``pytest.ini`` file)::
+
+    [pytest]
+    addopts = --no-start-live-server
+
+.. note::
+
+    Your **should manually start** live server after you finish your application
+    configuration and define all required routes:
+
+    .. code:: python
+
+        def test_add_endpoint_to_live_server(live_server):
+            @live_server.app.route('/test-endpoint')
+            def test_endpoint():
+                return 'got it', 200
+
+            live_server.start()
+
+            res = urlopen(url_for('test_endpoint', _external=True))
+            assert res.code == 200
+            assert b'got it' in res.read()
+
+
 ``request_ctx`` - request context
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

pytest_flask/__init__.py

@@ -1,4 +1,4 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
-__version__ = "0.9.0"
+__version__ = "0.10.0"

pytest_flask/fixtures.py

@@ -53,7 +53,6 @@ def __init__(self, app, port):
         self.app = app
         self.port = port
         self._process = None
-        self.start()
 
     def start(self):
         """Start application in a separate process."""
@@ -124,6 +123,9 @@ def test_server_is_up_and_running(live_server):
                         _rewrite_server_name(server_name, str(port)))
 
     server = LiveServer(app, port)
+    if request.config.getvalue('start_live_server'):
+        server.start()
+
     request.addfinalizer(server.stop)
     return server
 

pytest_flask/plugin.py

@@ -113,6 +113,18 @@ def test_something(app):
             monkeypatch.setitem(app.config, key.upper(), value)
 
 
+def pytest_addoption(parser):
+    group = parser.getgroup('flask')
+    group.addoption('--start-live-server',
+                    action="store_true", dest="start_live_server", default=True,
+                    help="start server automatically when live_server "
+                         "fixture is applyed (enabled by default).")
+    group.addoption('--no-start-live-server',
+                    action="store_false", dest="start_live_server",
+                    help="don't start server automatically when live_server "
+                         "fixture is applyed.")
+
+
 def pytest_configure(config):
     config.addinivalue_line(
         'markers',

tests/conftest.py

@@ -2,9 +2,13 @@
 # -*- coding: utf-8 -*-
 import pytest
 
+from textwrap import dedent
 from flask import Flask, jsonify
 
 
+pytest_plugins = 'pytester'
+
+
 @pytest.fixture
 def app():
     app = Flask(__name__)
@@ -19,3 +23,28 @@ def ping():
         return jsonify(ping='pong')
 
     return app
+
+
+@pytest.fixture
+def appdir(testdir):
+    app_root = testdir.tmpdir
+    test_root = app_root.mkdir('tests')
+
+    def create_test_module(code, filename='test_app.py'):
+        f = test_root.join(filename)
+        f.write(dedent(code), ensure=True)
+        return f
+
+    testdir.create_test_module = create_test_module
+
+    testdir.create_test_module('''
+        import pytest
+
+        from flask import Flask
+
+        @pytest.fixture
+        def app():
+            app = Flask(__name__)
+            return app
+    ''', filename='conftest.py')
+    return testdir

tests/test_live_server.py

@@ -33,3 +33,52 @@ def test_set_application_server_name(self, live_server):
     @pytest.mark.options(server_name='example.com:5000')
     def test_rewrite_application_server_name(self, live_server):
         assert live_server.app.config['SERVER_NAME'] == 'example.com:%d' % live_server.port
+
+    def test_prevent_starting_live_server(self, appdir):
+        appdir.create_test_module('''
+            import pytest
+
+            def test_a(live_server):
+                assert live_server._process is None
+        ''')
+
+        result = appdir.runpytest('-v', '--no-start-live-server')
+        result.stdout.fnmatch_lines(['*PASSED*'])
+        assert result.ret == 0
+
+    def test_start_live_server(self, appdir):
+        appdir.create_test_module('''
+            import pytest
+
+            def test_a(live_server):
+                assert live_server._process
+                assert live_server._process.is_alive()
+        ''')
+        result = appdir.runpytest('-v', '--start-live-server')
+        result.stdout.fnmatch_lines(['*PASSED*'])
+        assert result.ret == 0
+
+    def test_add_endpoint_to_live_server(self, appdir):
+        appdir.create_test_module('''
+            import pytest
+            try:
+                from urllib2 import urlopen
+            except ImportError:
+                from urllib.request import urlopen
+
+            from flask import url_for
+
+            def test_a(live_server):
+                @live_server.app.route('/new-endpoint')
+                def new_endpoint():
+                    return 'got it', 200
+
+                live_server.start()
+
+                res = urlopen(url_for('new_endpoint', _external=True))
+                assert res.code == 200
+                assert b'got it' in res.read()
+        ''')
+        result = appdir.runpytest('-v', '--no-start-live-server')
+        result.stdout.fnmatch_lines(['*PASSED*'])
+        assert result.ret == 0