HTTP_HOST middleware for storefronts (bug 769421)

docs/settings/settings_local.dev.py

@@ -41,6 +41,9 @@ DATABASES = {
     },
 }
 
+# To get browser ID to work on your local dev instance, add this.
+#SITE_URL_OVERRIDE = 'http://localhost:8000'
+
 # Skip indexing ES to speed things up?
 SKIP_SEARCH_INDEX = False
 

lib/httphost/__init__.py

@@ -0,0 +1 @@
+from .httphost import *

lib/httphost/context_processors.py

@@ -0,0 +1,7 @@
+from lib import httphost
+
+
+def httphost_context(request):
+    """Exposes SITE_URL and SUBDOMAIN to the request context."""
+    return {'SITE_URL': httphost.site_url(),
+            'SUBDOMAIN': httphost.subdomain()}

lib/httphost/httphost.py

@@ -0,0 +1,48 @@
+import re
+import threading
+
+from django.conf import settings
+from django.core.exceptions import ImproperlyConfigured
+
+app = threading.local()
+non_host_chars = re.compile(r'[^a-zA-Z0-9\.-]+')
+
+__all__ = ['site_url', 'subdomain']
+
+
+def site_url():
+    """
+    Gets the full subdomain of the host serving the request.
+
+    Example: https://marketplace.mozilla.org
+    """
+    if settings.SITE_URL_OVERRIDE:
+        if not settings.DEBUG:
+            raise ImproperlyConfigured('Cannot set SITE_URL_OVERRIDE in '
+                                       'production; it is set from HTTP_HOST')
+        return settings.SITE_URL_OVERRIDE
+    try:
+        return app.site_url
+    except AttributeError:
+        raise RuntimeError('Cannot access site_url() on a thread before a '
+                           'request has been made')
+
+
+def subdomain():
+    """
+    Gets the top-most subdomain of the host serving the request.
+
+    Example telefonica from telefonica.marketplace.mozilla.org
+    """
+    try:
+        return app.subdomain
+    except AttributeError:
+        raise RuntimeError('Cannot access site_url() on a thread before a '
+                           'request has been made')
+
+
+def set_host_info(host):
+    # In case someone is messing with the host header, scrub it.
+    host = non_host_chars.sub('', host)
+    app.site_url = 'https://%s' % host
+    app.subdomain = host.split('.')[0]

lib/httphost/middleware.py

@@ -0,0 +1,13 @@
+from .httphost import set_host_info
+
+
+class HTTPHostMiddleware:
+    """
+    Stores globally accessible metadata about the host.
+
+    This requires the server (Apache or whatever) to set HTTP_HOST.
+    """
+
+    def process_request(self, request):
+        # e.g. telefonica.marketplace.mozilla.org
+        set_host_info(request.META.get('HTTP_HOST', ''))

lib/httphost/tests.py

@@ -0,0 +1,83 @@
+import unittest
+
+from django.conf import settings
+from django.core.exceptions import ImproperlyConfigured
+from django.test.client import RequestFactory
+
+import mock
+from nose.tools import raises, eq_
+
+from lib import httphost
+from lib.httphost.context_processors import httphost_context
+from lib.httphost.middleware import HTTPHostMiddleware
+
+
+class UninitializedApp:
+    """stub for httphost.app"""
+
+
+class TestHTTPHost(unittest.TestCase):
+
+    def middleware(self, http_host):
+        serv = RequestFactory()
+        req = serv.get('/some/url')
+        req.META['HTTP_HOST'] = http_host
+        mw = HTTPHostMiddleware()
+        mw.process_request(req)
+
+    def context(self):
+        serv = RequestFactory()
+        return httphost_context(serv.get('/some/url'))
+
+    @mock.patch('lib.httphost.httphost.app', UninitializedApp)
+    @raises(RuntimeError)
+    def test_not_set(self):
+        httphost.site_url()
+
+    def test_site_url(self):
+        self.middleware('telefonica.marketplace.mozilla.org')
+        eq_(httphost.site_url(),
+            'https://telefonica.marketplace.mozilla.org')
+
+    @mock.patch.object(settings, 'DEBUG', True)
+    @mock.patch.object(settings, 'SITE_URL_OVERRIDE',
+                       'http://localhost:8000')
+    def test_site_url_override(self):
+        self.middleware('telefonica.marketplace.mozilla.org')
+        eq_(httphost.site_url(), 'http://localhost:8000')
+
+    @raises(ImproperlyConfigured)
+    @mock.patch.object(settings, 'DEBUG', False)
+    @mock.patch.object(settings, 'SITE_URL_OVERRIDE',
+                       'http://localhost:8000')
+    def test_cannot_override_site_url_in_prod(self):
+        httphost.site_url()
+
+    def test_subdomain(self):
+        self.middleware('telefonica.marketplace.mozilla.org')
+        eq_(httphost.subdomain(), 'telefonica')
+
+    def test_subdomain_amo(self):
+        self.middleware('addons.mozilla.org')
+        eq_(httphost.subdomain(), 'addons')
+
+    @mock.patch('lib.httphost.httphost.app', UninitializedApp)
+    @raises(RuntimeError)
+    def test_subdomain_not_set(self):
+        httphost.subdomain()
+
+    def test_subdomain_context(self):
+        self.middleware('telefonica.marketplace.mozilla.org')
+        eq_(self.context()['SUBDOMAIN'], 'telefonica')
+
+    def test_site_url_context(self):
+        self.middleware('marketplace.mozilla.org')
+        eq_(self.context()['SITE_URL'], 'https://marketplace.mozilla.org')
+
+    def test_site_url_is_scrubbed(self):
+        self.middleware('file:///etc/passwd')
+        eq_(httphost.site_url(), 'https://fileetcpasswd')
+
+    def test_subdomain_is_scrubbed(self):
+        self.middleware('file:///etc/passwd')
+        eq_(httphost.subdomain(), 'fileetcpasswd')

lib/settings_base.py

@@ -163,8 +163,15 @@ DOMAIN = HOSTNAME
 
 # Full base URL for your main site including protocol.  No trailing slash.
 #   Example: https://addons.mozilla.org
+# TODO(Kumar) when ready, remove this in place of httphost.site_url()
 SITE_URL = 'http://%s' % DOMAIN
 
+# The site URL is automatically determined with lib.httphost.HTTPHostMiddleware.
+# However, if you want to explicitly set it for local development,
+# you can do so here. This setting only works when DEBUG is True.
+#   Example: http://localhost:8000
+SITE_URL_OVERRIDE = None
+
 # Domain of the services site.  This is where your API, and in-product pages
 # live.
 SERVICES_DOMAIN = 'services.%s' % DOMAIN
@@ -268,6 +275,7 @@ TEMPLATE_CONTEXT_PROCESSORS = (
     'amo.context_processors.global_settings',
     'amo.context_processors.static_url',
     'jingo_minify.helpers.build_ids',
+    'lib.httphost.context_processors.httphost_context',
 )
 
 TEMPLATE_DIRS = (
@@ -328,6 +336,8 @@ MIDDLEWARE_CLASSES = (
     'access.middleware.ACLMiddleware',
 
     'commonware.middleware.ScrubRequestOnException',
+    # Set storefront related vars based on host.
+    'lib.httphost.middleware.HTTPHostMiddleware',
 )
 
 # Auth

settings_test.py

@@ -52,6 +52,7 @@ PAYPAL_PERMISSIONS_URL = ''
 
 STATIC_URL = ''
 SITE_URL = ''
+SITE_URL_OVERRIDE = None
 MOBILE_SITE_URL = ''
 MEDIA_URL = '/media/'
 # Reset these URLs to the defaults so your settings_local doesn't clobber them: