Invalid REST item spec returns 404 rather than 400.

A GET to /rest/data/issue/issue4 now returns a 404 rather than a 400
status code.

Author: rouilj

CHANGES.txt

@@ -96,6 +96,9 @@ Fixed:
   8-). Also supports shell and admin mode (John Rouillard)
 - Multiple fixes/updates for installation documentation.
   Including docker shell/admin/demo mdoes. (John Rouillard)
+- Invalid item identifiers passed to REST endpoint return a 404
+  rather than a 400 error. E.G. /rest/data/issue/issue4 (rather
+  than .../issue/4). (John Rouillard)
 
 Features:
 

roundup/rest.py

@@ -1002,7 +1002,11 @@ def get_element(self, class_name, item_id, input):
                     'Permission to view %s%s.%s denied'
                     % (class_name, item_id, keyprop)
                 )
-            itemid = class_obj.lookup(v)
+            try:
+                itemid = class_obj.lookup(v)
+            except TypeError:
+                raise NotFound("Item '%s' not found" % v)
+
         if not self.db.security.hasPermission(
             'View', uid, class_name, itemid=itemid
         ):

test/rest_common.py

@@ -1354,6 +1354,27 @@ def testBinaryFieldStorage(self):
         json_dict = json.loads(b2s(results))
         self.assertEqual(json_dict,expected)
 
+    
+    def testDispatchGet(self):
+        self.create_sampledata()
+
+        form = cgi.FieldStorage()
+        self.server.client.request.headers.get=self.get_header
+
+        for item in [ "55", "issue1", "1" ]:
+            print("test item: '%s'" % item)
+            results = self.server.dispatch("GET",
+                                           "/rest/data/issue/%s" % item,
+                                           form)
+            json_dict = json.loads(b2s(results))
+            try:
+                self.assertEqual(json_dict['error']['status'],  404)
+            except KeyError as e:
+                if e.args[0] == "error" and item == "1":
+                    pass
+                else:
+                    self.assertTrue(False)
+
     def testDispatchPost(self):
         """
         run POST through rest dispatch(). This also tests