Merge pull request #35 from cdent/issue-30

Guard against http_proxy and https_proxy

test/install.py

@@ -1,9 +1,10 @@
+import os
 import wsgi_intercept
 
 
 class BaseInstalledApp(object):
     def __init__(self, app, host, port=80, script_name='',
-                 install=None, uninstall=None):
+                 install=None, uninstall=None, proxy=None):
         self.app = app
         self.host = host
         self.port = port
@@ -12,6 +13,7 @@ class BaseInstalledApp(object):
         self._uninstall = uninstall or (lambda: None)
         self._hits = 0
         self._internals = {}
+        self._proxy = proxy
 
     def __call__(self, environ, start_response):
         self._hits += 1
@@ -32,10 +34,14 @@ class BaseInstalledApp(object):
         wsgi_intercept.remove_wsgi_intercept(self.host, self.port)
 
     def install(self):
+        if self._proxy:
+            os.environ['http_proxy'] = self._proxy
         self._install()
         self.install_wsgi_intercept()
 
     def uninstall(self):
+        if self._proxy:
+            del os.environ['http_proxy']
         self.uninstall_wsgi_intercept()
         self._uninstall()
 
@@ -56,9 +62,9 @@ def installer_class(module=None, install=None, uninstall=None):
         uninstall = uninstall or getattr(module, 'uninstall', None)
 
     class InstalledApp(BaseInstalledApp):
-        def __init__(self, app, host, port=80, script_name=''):
+        def __init__(self, app, host, port=80, script_name='', proxy=None):
             BaseInstalledApp.__init__(
                 self, app=app, host=host, port=port, script_name=script_name,
-                install=install, uninstall=uninstall)
+                install=install, uninstall=uninstall, proxy=proxy)
 
     return InstalledApp

test/test_http_client.py

@@ -42,6 +42,18 @@ def test_other():
         assert app.success()
 
 
+def test_proxy_handling():
+    """Proxy variable no impact."""
+    with InstalledApp(wsgi_app.simple_app, host=HOST, port=80,
+                      proxy='some.host:1234') as app:
+        http_client = http_lib.HTTPConnection(HOST)
+        http_client.request('GET', '/')
+        content = http_client.getresponse().read()
+        http_client.close()
+        assert content == b'WSGI intercept successful!\n'
+        assert app.success()
+
+
 def test_app_error():
     with InstalledApp(wsgi_app.raises_app, host=HOST, port=80):
         http_client = http_lib.HTTPConnection(HOST)

test/test_httplib2.py

@@ -47,6 +47,17 @@ def test_bogus_domain():
             'httplib2_intercept.HTTP_WSGIInterceptorWithTimeout("_nonexistant_domain_").connect()')
 
 
+def test_proxy_handling():
+    """Proxy has no impact."""
+    with InstalledApp(wsgi_app.simple_app, host=HOST, port=80,
+                      proxy='some_proxy.com:1234') as app:
+        http = httplib2.Http()
+        resp, content = http.request(
+            'http://some_hopefully_nonexistant_domain:80/')
+        assert content == b'WSGI intercept successful!\n'
+        assert app.success()
+
+
 def test_https():
     with InstalledApp(wsgi_app.simple_app, host=HOST, port=443) as app:
         http = httplib2.Http()

test/test_requests.py

@@ -1,3 +1,4 @@
+import os
 import py.test
 from wsgi_intercept import requests_intercept, WSGIAppError
 from test import wsgi_app
@@ -40,6 +41,18 @@ def test_bogus_domain():
             'requests.get("http://_nonexistant_domain_")')
 
 
+def test_proxy_handling():
+    with py.test.raises(RuntimeError) as exc:
+        with InstalledApp(wsgi_app.simple_app, host=HOST, port=80,
+                          proxy='some_proxy.com:1234'):
+            requests.get('http://some_hopefully_nonexistant_domain:80/')
+    assert 'http_proxy or https_proxy set in environment' in str(exc.value)
+    # We need to do this by hand because the exception was raised
+    # during the entry of the context manager, so the exit handler
+    # wasn't reached.
+    del os.environ['http_proxy']
+
+
 def test_https():
     with InstalledApp(wsgi_app.simple_app, host=HOST, port=443) as app:
         resp = requests.get('https://some_hopefully_nonexistant_domain:443/')

test/test_urllib.py

@@ -1,3 +1,4 @@
+import os
 import py.test
 from wsgi_intercept import urllib_intercept, WSGIAppError
 from test import wsgi_app
@@ -32,6 +33,19 @@ def test_http_other_port():
         assert environ['wsgi.url_scheme'] == 'http'
 
 
+def test_proxy_handling():
+    """Like requests, urllib gets confused about proxy early on."""
+    with py.test.raises(RuntimeError) as exc:
+        with InstalledApp(wsgi_app.simple_app, host=HOST, port=80,
+                          proxy='some.host:1234'):
+            url_lib.urlopen('http://some_hopefully_nonexistant_domain:80/')
+    assert 'http_proxy or https_proxy set in environment' in str(exc.value)
+    # We need to do this by hand because the exception was raised
+    # during the entry of the context manager, so the exit handler
+    # wasn't reached.
+    del os.environ['http_proxy']
+
+
 def test_https():
     with InstalledApp(wsgi_app.simple_app, host=HOST, port=443) as app:
         url_lib.urlopen('https://some_hopefully_nonexistant_domain:443/')

wsgi_intercept/__init__.py

@@ -50,6 +50,11 @@ Note especially that ``app_create_fn`` is a *function object* returning a WSGI
 application; ``script_name`` becomes ``SCRIPT_NAME`` in the WSGI app's
 environment, if set.
 
+Note also that if ``http_proxy`` or ``https_proxy`` is set in the environment
+this can cause difficulties with some of the intercepted libraries. If 
+requests or urllib is being used, these will raise an exception if one of
+those variables is set.
+
 Install
 =======
 

wsgi_intercept/requests_intercept.py

@@ -1,6 +1,7 @@
 """Intercept HTTP connections that use `requests <http://docs.python-requests.org/en/latest/>`_.
 """
 
+import os
 import sys
 
 from . import WSGI_HTTPConnection, WSGI_HTTPSConnection, wsgi_fake_socket
@@ -32,6 +33,9 @@ class HTTPS_WSGIInterceptor(WSGI_HTTPSConnection, HTTPSConnection):
 
 
 def install():
+    if 'http_proxy' in os.environ or 'https_proxy' in os.environ:
+        raise RuntimeError(
+            'http_proxy or https_proxy set in environment, please unset')
     HTTPConnectionPool.ConnectionCls = HTTP_WSGIInterceptor
     HTTPSConnectionPool.ConnectionCls = HTTPS_WSGIInterceptor
 

wsgi_intercept/urllib_intercept.py

@@ -1,5 +1,8 @@
 """Intercept HTTP connections that use urllib.request (Py3) aka urllib2 (Python 2).
 """
+
+import os
+
 try:
     import urllib.request as url_lib
 except ImportError:
@@ -27,6 +30,9 @@ class WSGI_HTTPSHandler(url_lib.HTTPSHandler):
 
 
 def install_opener():
+    if 'http_proxy' in os.environ or 'https_proxy' in os.environ:
+        raise RuntimeError(
+            'http_proxy or https_proxy set in environment, please unset')
     handlers = [WSGI_HTTPHandler()]
     if WSGI_HTTPSHandler is not None:
         handlers.append(WSGI_HTTPSHandler())