Retry error message

AUTHORS.rst

@@ -32,3 +32,4 @@ Patches and Suggestions
 - Jonathan Herriott
 - Job Evers
 - Cyrus Durgin
+- Luca Castoro

retrying.py

@@ -77,7 +77,8 @@ def __init__(self,
                  wait_func=None,
                  wait_jitter_max=None,
                  before_attempts=None,
-                 after_attempts=None):
+                 after_attempts=None,
+                 custom_message=None):
 
         self._stop_max_attempt_number = 5 if stop_max_attempt_number is None else stop_max_attempt_number
         self._stop_max_delay = 100 if stop_max_delay is None else stop_max_delay
@@ -92,6 +93,7 @@ def __init__(self,
         self._wait_jitter_max = 0 if wait_jitter_max is None else wait_jitter_max
         self._before_attempts = before_attempts
         self._after_attempts = after_attempts
+        self._custom_message = custom_message
 
         # TODO add chaining of stop behaviors
         # stop behavior
@@ -217,15 +219,16 @@ def should_reject(self, attempt):
     def call(self, fn, *args, **kwargs):
         start_time = int(round(time.time() * 1000))
         attempt_number = 1
+        message = self._custom_message if self._custom_message else fn.__name__
         while True:
             if self._before_attempts:
                 self._before_attempts(attempt_number)
 
             try:
-                attempt = Attempt(fn(*args, **kwargs), attempt_number, False)
+                attempt = Attempt(fn(*args, **kwargs), attempt_number, False, message)
             except:
                 tb = sys.exc_info()
-                attempt = Attempt(tb, attempt_number, True)
+                attempt = Attempt(tb, attempt_number, True, message)
 
             if not self.should_reject(attempt):
                 return attempt.get(self._wrap_exception)
@@ -257,10 +260,11 @@ class Attempt(object):
     occurred during the execution.
     """
 
-    def __init__(self, value, attempt_number, has_exception):
+    def __init__(self, value, attempt_number, has_exception, message):
         self.value = value
         self.attempt_number = attempt_number
         self.has_exception = has_exception
+        self.message = message
 
     def get(self, wrap_exception=False):
         """
@@ -278,9 +282,9 @@ def get(self, wrap_exception=False):
 
     def __repr__(self):
         if self.has_exception:
-            return "Attempts: {0}, Error:\n{1}".format(self.attempt_number, "".join(traceback.format_tb(self.value[2])))
+            return "Attempts: {0}, {1}, Error:\n{2}".format(self.attempt_number, self.message, "".join(traceback.format_tb(self.value[2])))
         else:
-            return "Attempts: {0}, Value: {1}".format(self.attempt_number, self.value)
+            return "Attempts: {0}, {1}, Value: {2}".format(self.attempt_number, self.message, self.value)
 
 
 class RetryError(Exception):

test_retrying.py

@@ -12,6 +12,7 @@
 ## See the License for the specific language governing permissions and
 ## limitations under the License.
 
+import sys
 import time
 import unittest
 
@@ -468,5 +469,31 @@ def _test_after():
 
         self.assertTrue(TestBeforeAfterAttempts._attempt_number is 2)
 
+class TestMeaningfulMessage(unittest.TestCase):
+
+    def test_function_name(self):
+
+        @retry(retry_on_result = lambda x: not x, stop_max_attempt_number = 5)
+        def just_a_function():
+            return 0
+
+        try:
+            just_a_function()
+            self.assertFalse(True)
+        except RetryError as ex:
+            self.assertTrue('just_a_function' in str(ex))
+
+    def test_custom_message(self):
+
+        @retry(retry_on_result = lambda x: not x, stop_max_attempt_number = 5, custom_message = 'hello world')
+        def just_a_function():
+            return 0
+
+        try:
+            just_a_function()
+            self.assertFalse(True)
+        except RetryError as ex:
+            self.assertTrue('hello world' in str(ex))
+
 if __name__ == '__main__':
     unittest.main()