1 files changed, 49 insertions, 0 deletions
diff --git a/middleware.py b/middleware.py
new file mode 100644
index 0000000..40e14ed
--- /dev/null
+++ b/middleware.py
@@ -0,0 +1,49 @@
+from django.conf import settings
+from django import http
+from django.core.urlresolvers import resolve
+
+class SmartAppendSlashMiddleware(object):
+    """
+    "SmartAppendSlash" middleware for taking care of URL rewriting.
+
+    This middleware appends a missing slash, if:
+    * the SMART_APPEND_SLASH setting is True
+    * the URL without the slash does not exist
+    * the URL with an appended slash does exist.
+    Otherwise it won't touch the URL.
+    """
+
+    def process_request(self, request):
+        """
+        Rewrite the URL based on settings.SMART_APPEND_SLASH
+        """
+
+        # Check for a redirect based on settings.SMART_APPEND_SLASH
+        host = http.get_host(request)
+        old_url = [host, request.path]
+        new_url = old_url[:]
+        # Append a slash if SMART_APPEND_SLASH is set and the resulting URL
+        # resolves.
+        if settings.SMART_APPEND_SLASH and (not old_url[1].endswith('/')) and not _resolves(old_url[1]) and _resolves(old_url[1] + '/'):
+            new_url[1] = new_url[1] + '/'
+            if settings.DEBUG and request.method == 'POST':
+                raise RuntimeError, "You called this URL via POST, but the URL doesn't end in a slash and you have SMART_APPEND_SLASH set. Django can't redirect to the slash URL while maintaining POST data. Change your form to point to %s%s (note the trailing slash), or set SMART_APPEND_SLASH=False in your Django settings." % (new_url[0], new_url[1])
+        if new_url != old_url:
+            # Redirect
+            if new_url[0]:
+                newurl = "%s://%s%s" % (request.is_secure() and 'https' or 'http', new_url[0], new_url[1])
+            else:
+                newurl = new_url[1]
+            if request.GET:
+                newurl += '?' + request.GET.urlencode()
+            return http.HttpResponsePermanentRedirect(newurl)
+
+        return None
+
+def _resolves(url):
+    try:
+        resolve(url)
+        return True
+    except http.Http404:
+        return False
+