Add cap_length helper

Change-Id: Ib864c7dc6c8c7bb849f4f97a1239eb5cc04c424c

6 files changed, 30 insertions, 12 deletions

diff --git a/swift/common/middleware/proxy_logging.py b/swift/common/middleware/proxy_logging.py
index d89343479..3cf2aee62 100644
--- a/swift/common/middleware/proxy_logging.py
+++ b/swift/common/middleware/proxy_logging.py
@@ -78,7 +78,7 @@ from swift.common.middleware.catch_errors import enforce_byte_count
 from swift.common.swob import Request
 from swift.common.utils import (get_logger, get_remote_client,
                                 config_true_value, reiterate,
-                                close_if_possible,
+                                close_if_possible, cap_length,
                                 InputProxy, list_from_csv, get_policy_index,
                                 split_path, StrAnonymizer, StrFormatTime,
                                 LogStringFormatter)
@@ -200,9 +200,7 @@ class ProxyLoggingMiddleware(object):
         env['swift.proxy_access_log_made'] = True
 
     def obscure_sensitive(self, value):
-        if value and len(value) > self.reveal_sensitive_prefix:
-            return value[:self.reveal_sensitive_prefix] + '...'
-        return value
+        return cap_length(value, self.reveal_sensitive_prefix)
 
     def obscure_req(self, req):
         for header in get_sensitive_headers():
diff --git a/swift/common/utils/__init__.py b/swift/common/utils/__init__.py
index 9c560aa71..3b4db177e 100644
--- a/swift/common/utils/__init__.py
+++ b/swift/common/utils/__init__.py
@@ -6483,6 +6483,15 @@ def strict_b64decode(value, allow_line_breaks=False):
         raise ValueError
 
 
+def cap_length(value, max_length):
+    if value and len(value) > max_length:
+        if isinstance(value, bytes):
+            return value[:max_length] + b'...'
+        else:
+            return value[:max_length] + '...'
+    return value
+
+
 MD5_BLOCK_READ_BYTES = 4096
 
 
diff --git a/swift/obj/ssync_receiver.py b/swift/obj/ssync_receiver.py
index b1e2ab072..345728a83 100644
--- a/swift/obj/ssync_receiver.py
+++ b/swift/obj/ssync_receiver.py
@@ -380,7 +380,8 @@ class Receiver(object):
             raise SsyncClientDisconnected
         if line.strip() != b':MISSING_CHECK: START':
             raise Exception(
-                'Looking for :MISSING_CHECK: START got %r' % line[:1024])
+                'Looking for :MISSING_CHECK: START got %r'
+                % utils.cap_length(line, 1024))
         object_hashes = []
         nlines = 0
         while True:
@@ -442,7 +443,8 @@ class Receiver(object):
             # Guess they hung up waiting for us to process the missing check
             raise SsyncClientDisconnected
         if line.strip() != b':UPDATES: START':
-            raise Exception('Looking for :UPDATES: START got %r' % line[:1024])
+            raise Exception('Looking for :UPDATES: START got %r'
+                            % utils.cap_length(line, 1024))
         successes = 0
         failures = 0
         updates = 0
diff --git a/swift/obj/ssync_sender.py b/swift/obj/ssync_sender.py
index 3f3bd9477..57f02e0e2 100644
--- a/swift/obj/ssync_sender.py
+++ b/swift/obj/ssync_sender.py
@@ -262,7 +262,7 @@ class Sender(object):
                 self.daemon.node_timeout, 'connect receive'):
             response = connection.getresponse()
             if response.status != http.HTTP_OK:
-                err_msg = response.read()[:1024]
+                err_msg = utils.cap_length(response.read(), 1024)
                 raise exceptions.ReplicationException(
                     'Expected status %s; got %s (%s)' %
                     (http.HTTP_OK, response.status, err_msg))
@@ -354,7 +354,7 @@ class Sender(object):
                     except UnicodeDecodeError:
                         pass
                 raise exceptions.ReplicationException(
-                    'Unexpected response: %r' % line[:1024])
+                    'Unexpected response: %r' % utils.cap_length(line, 1024))
         while True:
             with exceptions.MessageTimeout(
                     self.daemon.http_timeout, 'missing_check line wait'):
@@ -443,7 +443,7 @@ class Sender(object):
                     except UnicodeDecodeError:
                         pass
                 raise exceptions.ReplicationException(
-                    'Unexpected response: %r' % line[:1024])
+                    'Unexpected response: %r' % utils.cap_length(line, 1024))
         while True:
             with exceptions.MessageTimeout(
                     self.daemon.http_timeout, 'updates line wait'):
@@ -460,7 +460,7 @@ class Sender(object):
                     except UnicodeDecodeError:
                         pass
                 raise exceptions.ReplicationException(
-                    'Unexpected response: %r' % line[:1024])
+                    'Unexpected response: %r' % utils.cap_length(line, 1024))
 
     def send_subrequest(self, connection, method, url_path, headers, df):
         msg = [b'%s %s' % (method.encode('ascii'), url_path.encode('utf8'))]
diff --git a/swift/proxy/server.py b/swift/proxy/server.py
index a5ba1d858..64a14ff1d 100644
--- a/swift/proxy/server.py
+++ b/swift/proxy/server.py
@@ -36,7 +36,7 @@ from swift.common.utils import Watchdog, get_logger, \
     get_remote_client, split_path, config_true_value, generate_trans_id, \
     affinity_key_function, affinity_locality_predicate, list_from_csv, \
     parse_prefixed_conf, config_auto_int_value, node_to_string, \
-    config_request_node_count_value, config_percent_value
+    config_request_node_count_value, config_percent_value, cap_length
 from swift.common.registry import register_swift_info
 from swift.common.constraints import check_utf8, valid_api_version
 from swift.proxy.controllers import AccountController, ContainerController, \
@@ -736,7 +736,7 @@ class Application(object):
             else:
                 fmt = 'ERROR %(status)d %(body)s Trying to %(method)s ' \
                       '%(path)s From %(type)s Server'
-                values['body'] = body[:1024]
+                values['body'] = cap_length(body, 1024)
             self.error_occurred(node, fmt % values)
         else:
             ok = True
diff --git a/test/unit/common/test_utils.py b/test/unit/common/test_utils.py
index 772019c5a..3ad0432c3 100644
--- a/test/unit/common/test_utils.py
+++ b/test/unit/common/test_utils.py
@@ -4617,6 +4617,15 @@ cluster_dfw1 = http://dfw1.host/v1/
             self.fail('Invalid results from pure function:\n%s' %
                       '\n'.join(failures))
 
+    def test_cap_length(self):
+        self.assertEqual(utils.cap_length(None, 3), None)
+        self.assertEqual(utils.cap_length('', 3), '')
+        self.assertEqual(utils.cap_length('asdf', 3), 'asd...')
+        self.assertEqual(utils.cap_length('asdf', 5), 'asdf')
+
+        self.assertEqual(utils.cap_length(b'asdf', 3), b'asd...')
+        self.assertEqual(utils.cap_length(b'asdf', 5), b'asdf')
+
     def test_get_partition_for_hash(self):
         hex_hash = 'af088baea4806dcaba30bf07d9e64c77'
         self.assertEqual(43, utils.get_partition_for_hash(hex_hash, 6))