Issue 2559 - [cms] Detect conflicting pages in the development server

cms/bin/test_server.py

Index: cms/bin/test_server.py
===================================================================
--- a/cms/bin/test_server.py
+++ b/cms/bin/test_server.py
@@ -50,6 +50,15 @@
 # behavior by parsing local config files.
 mime_types = mimetypes.MimeTypes()
 
+class ConflictingPage(Exception):
+  pass
+
+def get_pages_and_localizable_files(source):
+  for page, format in source.list_pages():
+    yield page
+  for filename in source.list_localizable_files():
+    yield filename
+
 def get_data(path):
   if source.has_static(path):
     return source.read_static(path)
@@ -58,20 +67,43 @@
   if path == "":
     path = source.read_config().get("general", "defaultlocale")
   if "/" in path:
-    locale, page = path.split("/", 1)
+    locale, requested_page = path.split("/", 1)
   else:
-    locale, page = path, ""
+    locale, requested_page = path, ""
 
   default_page = source.read_config().get("general", "defaultpage")
-  alternative_page = "/".join([page, default_page]).lstrip("/")
+  alternative_page = "/".join([requested_page, default_page]).lstrip("/")
+
+  found_page = None
+  func = None
+  args = None
+
   for format in converters.iterkeys():
-    for p in (page, alternative_page):
-      if source.has_page(p, format):
-        return process_page(source, locale, p, format, "http://127.0.0.1:5000")
-  if source.has_localizable_file(locale, page):
-    return source.read_localizable_file(locale, page)
+    for page in (requested_page, alternative_page):
+      if source.has_page(page, format):
+        if found_page:
+          raise ConflictingPage("The requested page correpsonds to multiple files")
 
-  return None
+        found_page = page
+        func = process_page
+        args = (source, locale, page, format, "http://127.0.0.1:5000")
+
+  if source.has_localizable_file(locale, requested_page):
+    if found_page:
+      raise ConflictingPage("The requested page conflicts with a localizable file")
+
+    found_page = requested_page
+    func = source.read_localizable_file
+    args = (locale, requested_page)
+
+  if not found_page:
+    return None
+
+  for page in get_pages_and_localizable_files(source):
+    if page.startswith(found_page + "/") or found_page.startswith(page + "/"):
+      raise ConflictingPage("The requested path conflicts with the path of another page")
+
+  return func(*args)
 
 def show_error(start_response, status, **kwargs):
   env = jinja2.Environment(autoescape=True)
@@ -85,7 +117,7 @@
   path = environ.get("PATH_INFO")
 
   data = get_data(path)
-  if data == None:
+  if data is None:
     return show_error(start_response, "404 Not Found", uri=path)
 
   mime = mime_types.guess_type(path)[0] or "text/html"