- Added Post Traversal Hook and corresponding tests

lib/python/ZPublisher/BaseRequest.py

@@ -12,7 +12,7 @@
 ##############################################################################
 """ Basic ZPublisher request management.
 
-$Id: BaseRequest.py,v 1.54 2003/11/28 16:46:47 jim Exp $
+$Id: BaseRequest.py,v 1.55 2004/03/03 11:07:01 ctheune Exp $
 """
 
 from urllib import quote
@@ -252,6 +252,9 @@ class BaseRequest:
 
         request['TraversalRequestNameStack'] = request.path = path
 
+        # Set the posttraverse for duration of the traversal here
+        self._post_traverse = post_traverse = []
+
         entry_name = ''
         try:
             # We build parents in the wrong order, so we
@@ -376,6 +379,9 @@ class BaseRequest:
                 steps.append(entry_name)
         finally:
             parents.reverse()
+ 
+        # After traversal post traversal hooks aren't available anymore
+        del self._post_traverse
 
         request['PUBLISHED'] = parents.pop(0)
 
@@ -449,8 +455,21 @@ class BaseRequest:
         # Remove http request method from the URL.
         request['URL']=URL
 
+        # Run post traversal hooks here
+        result = None
+        if post_traverse:
+            result = exec_callables(post_traverse)
+
+        if result is not None:
+            object = result
+
         return object
 
+    def post_traverse(self, f, args=()):
+        """Set a callable object and argument tuple to be combined if traversal succeeds."""
+        if hasattr(self, "_post_traverse"):
+            self._post_traverse.append((f, tuple(args)))
+
     retry_count=0
     def supports_retry(self): return 0
 
@@ -459,8 +478,13 @@ class BaseRequest:
         """
         self._held=self._held+(object,)
 
-
-
+def exec_callables(callables):
+    result = None
+    for (f, args) in callables:
+        # Don't catch exceptions here. And don't hide them anyway.
+        result = f(*args)
+        if result is not None:
+            return result
 
 def old_validation(groups, request, auth,
                    roles=UNSPECIFIED_ROLES):

lib/python/ZPublisher/tests/testPostTraversal.py

+from unittest import TestCase, TestSuite, makeSuite, main
+
+import Zope
+Zope.startup()
+
+from Acquisition import Implicit
+from ZPublisher.BaseRequest import BaseRequest
+from ZPublisher.HTTPResponse import HTTPResponse
+
+
+# Various post traversal methods
+
+pt_simple_was_run = 0
+
+def pt_simple():
+    global pt_simple_was_run 
+    pt_simple_was_run = 1
+    pass
+
+def pt_static_arg(request, b):
+    request.set('b', b)
+    pass
+
+def pt_simple_redirect(a):
+    return a
+
+def pt_chain_test(request, string):
+    request.set('a', request.get('a', '') + string)
+
+class DummyObjectBasic(Implicit):
+    """ Dummy class with docstring.
+    """
+
+    def _setObject(self, id, object):
+        setattr(self, id, object)
+        return getattr(self, id)
+
+    def view(self):
+        """ Attribute with docstring.
+        """
+        return 'view content'
+
+class DummyObjectWithPTHook(DummyObjectBasic):
+    """ Dummy class with docstring.
+    """
+
+    traversal = []
+
+    def __before_publishing_traverse__(self, object, REQUEST):
+        for x in self.traversal:
+            REQUEST.post_traverse(*x)
+
+class TestBaseRequestPT(TestCase):
+
+    def setUp(self):
+        self.root = DummyObjectBasic()
+        self.f1 = self.root._setObject('folder', DummyObjectBasic() )
+        self.f1._setObject('objBasic', DummyObjectWithPTHook() )
+
+    def makeBaseRequest(self):
+        response = HTTPResponse()
+        environment = { 'URL': '',
+                        'PARENTS': [self.root],
+                        'steps': [],
+                        '_hacked_path': 0,
+                        '_test_counter': 0,
+                        'response': response }
+        return BaseRequest(environment)
+
+    def test_post_basic(self):
+        global pt_simple_was_run
+        pt_simple_was_run = 0
+        r = self.makeBaseRequest()
+        
+        # Set hook
+        self.f1.objBasic.traversal = [(pt_simple,)]
+        x = r.traverse('folder/objBasic')
+        
+        # Object should be self.f1.objBasic
+        self.assertEqual(x, self.f1.objBasic)
+        self.assertEqual(pt_simple_was_run, 1)
+
+        self.f1.objBasic.traversal = []
+
+    def test_post_arg(self):
+
+        r = self.makeBaseRequest()
+        b = 1
+
+        self.f1.objBasic.traversal = [(pt_static_arg, (r, b))]
+        x = r.traverse('folder/objBasic')
+
+        # Object should have been traversed normally
+        self.assertEqual(x, self.f1.objBasic)
+        self.assertEqual(r.get('b', 0), b)
+
+        self.f1.objBasic.traversal = []
+
+    def test_hook_chain(self):
+
+        r = self.makeBaseRequest()
+
+        self.f1.objBasic.traversal = [ (pt_chain_test, (r, 'a')),
+                                       (pt_chain_test, (r, 'b')),
+                                       (pt_chain_test, (r, 'c')),
+                                       (pt_chain_test, (r, 'd'))]
+
+        x = r.traverse('folder/objBasic')
+        self.assertEqual(r.get('a',''), 'abcd')
+
+        self.f1.objBasic.traversal = []
+
+    def test_hook_redirect(self):
+        r = self.makeBaseRequest()
+        check = []
+        self.f1.objBasic.traversal = [(pt_simple_redirect, (check,))]
+
+        x = r.traverse('folder/objBasic')
+
+        self.assertEqual(x, check)
+ 
+    def test_hook_chain_redirect(self):
+        r = self.makeBaseRequest()
+        check = []
+        self.f1.objBasic.traversal = [ (pt_chain_test, (r, 'a')),
+                                       (pt_chain_test, (r, 'b')),
+                                       (pt_chain_test, (r, 'c')),
+                                       (pt_simple_redirect, (check,)),
+                                       (pt_simple_redirect, (1,)),
+                                       (pt_chain_test, (r, 'd'))]
+
+        x = r.traverse('folder/objBasic')
+
+        self.assertEqual(r.get('a',''), 'abc')
+        self.assertEqual(x, check)
+
+def test_suite():
+    return TestSuite( ( makeSuite(TestBaseRequestPT), ) )
+
+if __name__ == '__main__':
+    main(defaultTest='test_suite')