Changeset 0339ba9 in trunk

Timestamp:

2020-10-16T13:52:41Z (4 years ago)

Author:

Jean-Paul Calderone <exarkun@…>

Branches:

master

Children:

0faa24d

Parents:

fa02e46

git-author:

Jean-Paul Calderone <exarkun@…> (2020-10-15 20:14:06)

git-committer:

Jean-Paul Calderone <exarkun@…> (2020-10-16 13:52:41)

Message:

Turn getChild None and Deferred results into something Twisted Web can manage

File:

• src/allmydata/web/common.py (modified) (2 diffs)

src/allmydata/web/common.py ¶

@@ -21 +21 @@
 )
 from twisted.web.util import (
+    DeferredResource,
     FailureElement,
     redirectTo,
@@ -460 +461 @@
 
 
-def exception_to_child(f):
+def exception_to_child(getChild):
     """
     Decorate ``getChild`` method with exception handling behavior to render an
     error page reflecting the exception.
     """
-    @wraps(f)
+    @wraps(getChild)
     def g(self, name, req):
-        try:
-            return f(self, name, req)
-        except Exception as e:
-            description, status = humanize_exception(e)
-            return resource.ErrorPage(status, "Error", description)
+        bound_getChild = getChild.__get__(self, type(self))
+        result = maybeDeferred(bound_getChild, name, req)
+        result.addCallbacks(
+            _getChild_done,
+            _getChild_failed,
+            callbackArgs=(self,),
+        )
+        return DeferredResource(result)
     return g
+
+
+def _getChild_done(child, parent):
+    if child is None:
+        return resource.NoResource()
+    return child
+
+
+def _getChild_failed(reason):
+    text, code = humanize_failure(reason)
+    return resource.ErrorPage(code, "Error", text)