Add generic Geo redirector view class

* Support full URLs as well as URL names
* Add docs and never cache headers
* Clean up the view docs a bit

Fix #6084

bedrock/base/tests/test_views.py

@@ -3,7 +3,7 @@ import json
 from django.test import TestCase, RequestFactory
 from django.test import override_settings
 
-from bedrock.base.views import geolocate
+from bedrock.base.views import geolocate, GeoRedirectView
 
 
 class TestGeolocate(TestCase):
@@ -33,3 +33,53 @@ class TestGeolocate(TestCase):
     def test_dev_mode(self):
         # should match the setting in DEV mode
         self.assertDictEqual(self.get_country('US'), {'country_code': 'DE'})
+
+
+geo_view = GeoRedirectView.as_view(
+    geo_urls={
+        'CA': 'firefox.new',
+        'US': 'firefox',
+    },
+    default_url='https://abide.dude'
+)
+
+
+@override_settings(DEV=False)
+class TestGeoRedirectView(TestCase):
+    def get_response(self, country):
+        rf = RequestFactory()
+        req = rf.get('/', HTTP_CF_IPCOUNTRY=country)
+        return geo_view(req)
+
+    def test_special_country(self):
+        resp = self.get_response('CA')
+        assert resp.status_code == 302
+        assert resp['location'] == '/firefox/new/'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'
+
+        resp = self.get_response('US')
+        assert resp.status_code == 302
+        assert resp['location'] == '/firefox/'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'
+
+    def test_other_country(self):
+        resp = self.get_response('DE')
+        assert resp.status_code == 302
+        assert resp['location'] == 'https://abide.dude'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'
+
+        resp = self.get_response('JA')
+        assert resp.status_code == 302
+        assert resp['location'] == 'https://abide.dude'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'
+
+    def test_invalid_country(self):
+        resp = self.get_response('dude')
+        assert resp.status_code == 302
+        assert resp['location'] == 'https://abide.dude'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'
+
+        resp = self.get_response('42')
+        assert resp.status_code == 302
+        assert resp['location'] == 'https://abide.dude'
+        assert resp['cache-control'] == 'max-age=0, no-cache, no-store, must-revalidate'

bedrock/base/views.py

@@ -1,6 +1,7 @@
 import json
 import logging
 import os.path
+import re
 from datetime import datetime
 from os import getenv
 from time import time
@@ -9,6 +10,8 @@ import timeago
 from django.conf import settings
 from django.http import HttpResponse, HttpResponseBadRequest, JsonResponse
 from django.shortcuts import render
+from django.utils.decorators import method_decorator
+from django.views.generic import RedirectView
 from django.views.decorators.cache import never_cache
 from django.views.decorators.csrf import csrf_exempt
 from django.views.decorators.http import require_POST, require_safe
@@ -31,6 +34,26 @@ def get_geo_from_request(request):
     return country_code.upper()
 
 
+@method_decorator(never_cache, name='dispatch')
+class GeoRedirectView(RedirectView):
+    # dict of country codes to full URLs or URL names
+    geo_urls = None
+    # default URL or URL name for countries not in `geo_urls`
+    default_url = None
+    # default to sending the query parameters through to the redirect
+    query_string = True
+
+    def get_redirect_url(self, *args, **kwargs):
+        country_code = get_geo_from_request(self.request)
+        url = self.geo_urls.get(country_code, self.default_url)
+        if re.match(r'https?://', url, re.I):
+            self.url = url
+        else:
+            self.pattern_name = url
+
+        return super().get_redirect_url(*args, **kwargs)
+
+
 @require_safe
 @never_cache
 def geolocate(request):

docs/coding.rst

@@ -15,11 +15,15 @@ URL patterns should be as strict as possible. It should begin with a
 `^` and end with `/$` to make sure it only matches what you specifiy.
 It also forces a trailing slash. You should also give the URL a name
 so that other pages can reference it instead of hardcoding the URL.
-Example::
+Example:
+
+.. code-block:: python
 
     url(r'^channel/$', channel, name='mozorg.channel')
 
-Bedrock comes with a handy shortcut to automate all of this::
+Bedrock comes with a handy shortcut to automate all of this:
+
+.. code-block:: python
 
     from bedrock.mozorg.util import page
     page('channel', 'mozorg/channel.html')
@@ -28,6 +32,8 @@ You don't even need to create a view. It will serve up the specified
 template at the given URL (the first parameter). You can also pass
 template data as keyword arguments:
 
+.. code-block:: python
+
     page('channel', 'mozorg/channel.html',
          latest_version=product_details.firefox_versions['LATEST_FIREFOX_VERSION'])
 
@@ -62,23 +68,31 @@ Images should be included on pages using helper functions.
 
 static()
 ^^^^^^^^
-For a simple image, the `static()` function is used to generate the image URL. For example::
+For a simple image, the `static()` function is used to generate the image URL. For example:
+
+.. code-block:: html
 
     <img src="{{ static('img/firefox/new/firefox-logo.png') }}" alt="Firefox" />
 
-will output an image::
+will output an image:
+
+.. code-block:: html
 
     <img src="/media/img/firefox/new/firefox-logo.png" alt="Firefox">
 
 high_res_img()
 ^^^^^^^^^^^^^^
-For images that include a high-resolution alternative for displays with a high pixel density, use the `high_res_img()` function::
+For images that include a high-resolution alternative for displays with a high pixel density, use the `high_res_img()` function:
+
+.. code-block:: python
 
     high_res_img('firefox/new/firefox-logo.png', {'alt': 'Firefox', 'width': '200', 'height': '100'})
 
 The `high_res_img()` function will automatically look for the image in the URL parameter suffixed with `'-high-res'`, e.g. `firefox/new/firefox-logo-high-res.png` and switch to it if the display has high pixel density.
 
-`high_res_img()` supports localized images by setting the `'l10n'` parameter to `True`::
+`high_res_img()` supports localized images by setting the `'l10n'` parameter to `True`:
+
+.. code-block:: python
 
     high_res_img('firefox/new/firefox-logo.png', {'l10n': True, 'alt': 'Firefox', 'width': '200', 'height': '100'})
 
@@ -86,7 +100,9 @@ When using localization, `high_res_img()` will look for images in the appropriat
 
 l10n_img()
 ^^^^^^^^^^
-Images that have translatable text can be handled with `l10n_img()`::
+Images that have translatable text can be handled with `l10n_img()`:
+
+.. code-block:: html
 
     <img src="{{ l10n_img('firefox/os/have-it-all/messages.jpg') }}" />
 
@@ -94,13 +110,17 @@ The images referenced by `l10n_img()` must exist in `media/img/l10n/`, so for ab
 
 platform_img()
 ^^^^^^^^^^^^^^
-Finally, for outputting an image that differs depending on the platform being used, the `platform_img()` function will automatically display the image for the user's browser::
+Finally, for outputting an image that differs depending on the platform being used, the `platform_img()` function will automatically display the image for the user's browser:
+
+.. code-block:: python
 
     platform_img('firefox/new/browser.png', {'alt': 'Firefox screenshot'})
 
 `platform_img()` will automatically look for the images `browser-mac.png`, `browser-win.png`, `browser-linux.png`, etc. Platform image also supports hi-res images by adding `'high-res': True` to the list of optional attributes.
 
-`platform_img()` supports localized images by setting the `'l10n'` parameter to `True`::
+`platform_img()` supports localized images by setting the `'l10n'` parameter to `True`:
+
+.. code-block:: python
 
     platform_img('firefox/new/firefox-logo.png', {'l10n': True, 'alt': 'Firefox screenshot'})
 
@@ -110,35 +130,57 @@ Writing Views
 -------------
 
 You should rarely need to write a view for mozilla.org. Most pages are
-static and you should use the `page` expression documented above.
+static and you should use the `page` function documented above.
 
-If you need to write a view and the page has a newsletter signup form
-in the footer (most do), make sure to handle this in your view.
-Bedrock comes with a function for doing this automatically::
+If you need to write a view and the page is translated or translatable
+then it should use the `l10n_utils.render()` function to render the
+template.
 
-    from bedrock.mozorg.util import handle_newsletter
-    from django.views.decorators.csrf import csrf_exempt
+.. code-block:: python
 
-    @csrf_exempt
-    def view(request):
-        ctx = handle_newsletter(request)
+    from lib import l10n_utils
+
+    def my_view(request):
+        # do your fancy things
+        ctx = {'template_variable': 'awesome data'}
         return l10n_utils.render(request, 'app/template.html', ctx)
 
-You'll notice a few other things in there. You should use the
-`l10n_utils.render` function to render templates because it handles
-special l10n work for us. Since we're handling the newsletter form
-post, you also need the `csrf_exempt` decorator.
-
 Make sure to namespace your templates by putting them in a directory
 named after your app, so instead of templates/template.html they would
 be in templates/blog/template.html if `blog` was the name of your app.
 
+
+If you prefer to use Django's Generic View classes we have a convenient
+helper for that. You can use it either to create a custom view class of
+your own, or use it directly in a `urls.py` file.
+
+.. code-block:: python
+
+    # app/views.py
+    from lib.l10n_utils import L10nTemplateView
+
+    class FirefoxRoxView(L10nTemplateView):
+        template_name = 'app/firefox-rox.html'
+
+    # app/urls.py
+    urlpatterns = [
+        # from views.py
+        path('firefox/rox/', FirefoxRoxView.as_view()),
+        # directly
+        path('firefox/sox/', L10nTemplateView.as_view(template_name='app/firefox-sox.html')),
+    ]
+
+The `L10nTemplateView` functionality is mostly in a template mixin called `LangFilesMixin` which
+you can use with other generic Django view classes if you need one other than `TemplateView`.
+
 Variation Views
 ^^^^^^^^^^^^^^^
 
 We have a generic view that allows you to easily create and use a/b testing
 templates. If you'd like to have either separate templates or just a template
-context variable for switching, this will help you out. For example::
+context variable for switching, this will help you out. For example.
+
+.. code-block:: python
 
     # urls.py
 
@@ -157,12 +199,16 @@ This will give you a context variable called `variation` that will either be an
 string if no param is set, or `a` if `?v=a` is in the URL, or `b` if `?v=b` is in the
 URL. No other options will be valid for the `v` query parameter and `variation` will
 be empty if any other value is passed in for `v` via the URL. So in your template code
-you'd simply do the following::
+you'd simply do the following:
+
+.. code-block:: jinja
 
     {% if variation == 'b' %}<p>This is the B variation of our test. Enjoy!</p>{% endif %}
 
 If you'd rather have a fully separate template for your test, you can use the
-`template_name_variations` argument to the view instead of `template_context_variations`::
+`template_name_variations` argument to the view instead of `template_context_variations`.
+
+.. code-block:: python
 
     # urls.py
 
@@ -191,7 +237,9 @@ You can also limit your variations to certain locales. By default the variations
 for any localization of the page, but if you supply a list of locales to the `variation_locales`
 argument to the view then it will only set the variation context variable or alter the template
 name (depending on the options explained above) when requested at one of said locales. For example,
-the template name example above could be modified to only work for English or German like so::
+the template name example above could be modified to only work for English or German like so
+
+.. code-block:: python
 
     # urls.py
 
@@ -216,6 +264,39 @@ valid variation were given in the URL.
     a mixin that implements this pattern that should work with most views:
     `bedrock.utils.views.VariationMixin`.
 
+
+Geo Redirect View
+^^^^^^^^^^^^^^^^^
+
+We sometimes need to have a special page variation for people visiting from certain
+countries. To make this easier we have a redirect view class that will allow you to
+define URLs per country as well as a default for everyone else. This redirector URL
+must only be a redirector since it must be uncachable by our CDN so that all visitors
+will hit the server and see the correct page for their location.
+
+.. code-block:: python
+
+    from bedrock.base.views import GeoRedirectView
+
+    class CanadaIsSpecialView(GeoRedirectView):
+        geo_urls = {
+            'CA': 'app.canada-is-special',
+        }
+        default_url = 'app.everyone-else'
+
+In this example people in Canada would go to the URL that Django returns using `reverse()`
+(i.e. the name of the URL) and everyone else would go to the `app.everyone-else` URL. You
+may also use full URLs instead of URL names if you want to. It will look for strings that
+start with "http(s)://" and use it as is. The
+`country code <https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Officially_assigned_code_elements>`_
+must be 2 characters and upper case. If the patterns for the redirect and the destination(s) have
+URL parameters they will be passed to the reverse call for the URL pattern name. So for example
+if you're doing this for a Firefox page with a version number in the URL, as long as the view
+and destination URLs use the same URL parameter names it will be preserved in the resulting destination URL.
+So `/firefox/70.0beta/whatsnew/` would redirect to `/firefox/70.0beta/whatsnew/canada/` for example.
+The redirector will also preserve query parameters by default. You can turn that off by
+setting the `query_string = False` class variable.
+
 Coding Style Guides
 -------------------
 

lib/l10n_utils/__init__.py

@@ -10,6 +10,7 @@ from django.http import HttpResponseRedirect
 from django.shortcuts import render as django_render
 from django.template import TemplateDoesNotExist, loader
 from django.utils.translation.trans_real import parse_accept_lang_header
+from django.views.generic import TemplateView
 
 from bedrock.base.urlresolvers import split_path
 
@@ -164,7 +165,7 @@ class LangFilesMixin:
     add_active_locales = None
 
     def get_context_data(self, **kwargs):
-        ctx = super(LangFilesMixin, self).get_context_data(**kwargs)
+        ctx = super().get_context_data(**kwargs)
         if self.active_locales:
             ctx['active_locales'] = self.active_locales
         if self.add_active_locales:
@@ -175,3 +176,7 @@ class LangFilesMixin:
     def render_to_response(self, context, **response_kwargs):
         return render(self.request, self.get_template_names(),
                       context, **response_kwargs)
+
+
+class L10nTemplateView(LangFilesMixin, TemplateView):
+    pass