github: Add sign up button on registration page.

templates/zerver/accounts_home.html

@@ -65,15 +65,28 @@ $(function () {
                         {% endfor %}
                     {% endif %}
 
-                    {% if google_auth_enabled %}
+                    {% if any_oauth_backend_enabled %}
                     <div class="or">or</div>
+                    {% endif %}
 
+                    {% if google_auth_enabled %}
                     <div class="register-google">
                         <a href="{{ url('zerver.views.auth.start_google_oauth2') }}">
                             <button class="login-google-button full-width">{{ _('Sign up with Google') }}</button>
                         </a>
                     </div>
                     {% endif %}
+
+                    {% if github_auth_enabled %}
+                    <div class="login-github">
+                        <a href="{{ url('signup-social', args=('github',)) }}"
+                           class="github-wrapper">
+                            <button class="login-github-button github">
+                                <span>{{ _('Sign up with GitHub') }}</span>
+                            </button>
+                        </a>
+                    </div>
+                    {% endif %}
                     {% endif %}
                 </div>
             </div>

zerver/tests/test_auth_backends.py

@@ -677,6 +677,13 @@ class GitHubAuthBackendTest(ZulipTestCase):
         # type: () -> None
         result = self.client_get('/accounts/login/social/github')
         self.assertIn(reverse('social:begin', args=['github']), result.url)
+        self.assertIn('is_signup=0', result.url)
+
+    def test_signup_url(self):
+        # type: () -> None
+        result = self.client_get('/accounts/register/social/github')
+        self.assertIn(reverse('social:begin', args=['github']), result.url)
+        self.assertIn('is_signup=1', result.url)
 
     def test_github_complete(self):
         # type: () -> None

zerver/views/auth.py

@@ -233,6 +233,11 @@ def start_social_login(request, backend):
     backend_url = reverse('social:begin', args=[backend])
     return redirect_to_main_site(request, backend_url)
 
+def start_social_signup(request, backend):
+    # type: (HttpRequest, Text) -> HttpResponse
+    backend_url = reverse('social:begin', args=[backend])
+    return redirect_to_main_site(request, backend_url, is_signup=True)
+
 def send_oauth_request_to_google(request):
     # type: (HttpRequest) -> HttpResponse
     subdomain = request.GET.get('subdomain', '')

zproject/urls.py

@@ -101,6 +101,9 @@ i18n_urls = [
     url(r'^avatar/(?P<email_or_id>[\S]+)?', zerver.views.users.avatar, name='zerver.views.users.avatar'),
 
     # Registration views, require a confirmation ID.
+    url(r'^accounts/register/social/(\w+)$',
+        zerver.views.auth.start_social_signup,
+        name='signup-social'),
     url(r'^accounts/home/', zerver.views.registration.accounts_home,
         name='zerver.views.registration.accounts_home'),
     url(r'^accounts/send_confirm/(?P<email>[\S]+)?',