PYTHON-1787: add details to OperationFailure exception and NotMasterError (#448)

PYTHON-1787-add details to OperationFailure and NotMasterError by adding a __repr__ function

https://jira.mongodb.org/browse/PYTHON-1787

doc/contributors.rst

@@ -87,3 +87,4 @@ The following is a list of people who have contributed to
 - Felipe Rodrigues(fbidu)
 - Terence Honles (terencehonles)
 - Paul Fisher (thetorpedodog)
+- Julius Park (juliusgeo)

pymongo/errors.py

@@ -113,7 +113,11 @@ class NotMasterError(AutoReconnect):
 
     Subclass of :exc:`~pymongo.errors.AutoReconnect`.
     """
-
+    def __str__(self):
+        output_str = "%s, full error: %s" % (self._message, self.__details)
+        if sys.version_info[0] == 2 and isinstance(output_str, unicode):
+            return output_str.encode('utf-8', errors='replace')
+        return output_str
 
 class ServerSelectionTimeoutError(AutoReconnect):
     """Thrown when no MongoDB server is available for an operation
@@ -167,6 +171,11 @@ class OperationFailure(PyMongoError):
         """
         return self.__details
 
+    def __str__(self):
+        output_str = "%s, full error: %s" % (self._message, self.__details)
+        if sys.version_info[0] == 2 and isinstance(output_str, unicode):
+            return output_str.encode('utf-8', errors='replace')
+        return output_str
 
 class CursorNotFound(OperationFailure):
     """Raised while iterating query results if the cursor is

test/test_database.py

@@ -972,7 +972,7 @@ class TestDatabase(IntegrationTest):
         with self.assertRaises(OperationFailure) as context:
             helpers._check_command_response(error_document)
 
-        self.assertEqual('inner', str(context.exception))
+        self.assertIn('inner', str(context.exception))
 
         # If a shard has no primary and you run a command like dbstats, which
         # cannot be run on a secondary, mongos's response includes empty "raw"
@@ -985,7 +985,7 @@ class TestDatabase(IntegrationTest):
         with self.assertRaises(OperationFailure) as context:
             helpers._check_command_response(error_document)
 
-        self.assertEqual('outer', str(context.exception))
+        self.assertIn('outer', str(context.exception))
 
         # Raw error has ok: 0 but no errmsg. Not a known case, but test it.
         error_document = {
@@ -996,7 +996,7 @@ class TestDatabase(IntegrationTest):
         with self.assertRaises(OperationFailure) as context:
             helpers._check_command_response(error_document)
 
-        self.assertEqual('outer', str(context.exception))
+        self.assertIn('outer', str(context.exception))
 
     @client_context.require_test_commands
     @client_context.require_no_mongos