Add VERBOSE_EXCEPTIONS flag to suppress doc content in JsonPointerException messages

jsonpointer.py

@@ -45,6 +45,10 @@
 
 _nothing = object()
 
+# If True, exceptions include the doc content in the error message.
+# Set to False to suppress potentially large document content from exceptions.
+VERBOSE_EXCEPTIONS = True
+
 
 def set_pointer(doc, pointer, value, inplace=True):
     """Resolves a pointer against doc and sets the value of the target within doc.
@@ -271,7 +275,10 @@ def walk(self, doc, part):
             return doc[part]
 
         except KeyError:
-            raise JsonPointerException("member '%s' not found in %s" % (part, doc))
+            if VERBOSE_EXCEPTIONS:
+                raise JsonPointerException("member '%s' not found in %s" % (part, doc))
+            else:
+                raise JsonPointerException("member '%s' not found" % (part,))
 
     def contains(self, ptr):
         """ Returns True if self contains the given ptr """

tests.py

@@ -391,6 +391,35 @@ def test_mock_dict_raises_key_error(self):
         self.assertRaises(JsonPointerException, resolve_pointer, doc, '/root/1/2/3/4')
 
 
+class VerboseExceptionsTests(unittest.TestCase):
+
+    def setUp(self):
+        # Save original value and ensure verbose mode is on for each test
+        self._original = jsonpointer.VERBOSE_EXCEPTIONS
+        jsonpointer.VERBOSE_EXCEPTIONS = True
+
+    def tearDown(self):
+        jsonpointer.VERBOSE_EXCEPTIONS = self._original
+
+    def test_verbose_exception_includes_doc(self):
+        doc = {'foo': 1}
+        try:
+            resolve_pointer(doc, '/bar')
+            self.fail('Expected JsonPointerException')
+        except JsonPointerException as e:
+            self.assertIn(repr(doc), str(e))
+
+    def test_non_verbose_exception_excludes_doc(self):
+        doc = {'foo': 1}
+        jsonpointer.VERBOSE_EXCEPTIONS = False
+        try:
+            resolve_pointer(doc, '/bar')
+            self.fail('Expected JsonPointerException')
+        except JsonPointerException as e:
+            self.assertNotIn(repr(doc), str(e))
+            self.assertIn('bar', str(e))
+
+
 def load_tests(loader, tests, ignore):
     tests.addTests(doctest.DocTestSuite(jsonpointer))
     return tests