Move InputProxy to utils

This class is being used at least by Ceilometer in its Swift middleware, and
since it's a general one anyway, it looks good to move it to common.utils.

This is a follow-up to Chmouel suggestion in
https://review.openstack.org/#/c/18231

Change-Id: I8d0ed8600c4152b91be9a88a3b396c3967d0add2
Signed-off-by: Julien Danjou <julien@danjou.info>

swift/common/middleware/proxy_logging.py

@@ -42,47 +42,8 @@ from urllib import quote, unquote
 
 from swift.common.swob import Request
 from swift.common.utils import (get_logger, get_remote_client,
-                                get_valid_utf8_str, config_true_value)
+                                get_valid_utf8_str, config_true_value,
-
+                                InputProxy)
-
-class InputProxy(object):
-    """
-    File-like object that counts bytes read.
-    To be swapped in for wsgi.input for accounting purposes.
-    """
-    def __init__(self, wsgi_input):
-        """
-        :param wsgi_input: file-like object to wrap the functionality of
-        """
-        self.wsgi_input = wsgi_input
-        self.bytes_received = 0
-        self.client_disconnect = False
-
-    def read(self, *args, **kwargs):
-        """
-        Pass read request to the underlying file-like object and
-        add bytes read to total.
-        """
-        try:
-            chunk = self.wsgi_input.read(*args, **kwargs)
-        except Exception:
-            self.client_disconnect = True
-            raise
-        self.bytes_received += len(chunk)
-        return chunk
-
-    def readline(self, *args, **kwargs):
-        """
-        Pass readline request to the underlying file-like object and
-        add bytes read to total.
-        """
-        try:
-            line = self.wsgi_input.readline(*args, **kwargs)
-        except Exception:
-            self.client_disconnect = True
-            raise
-        self.bytes_received += len(line)
-        return line
 
 
 class ProxyLoggingMiddleware(object):

swift/common/utils.py

@@ -1524,3 +1524,43 @@ def reiterate(iterable):
             return itertools.chain([chunk], iterable)
         except StopIteration:
             return []
+
+
+class InputProxy(object):
+    """
+    File-like object that counts bytes read.
+    To be swapped in for wsgi.input for accounting purposes.
+    """
+    def __init__(self, wsgi_input):
+        """
+        :param wsgi_input: file-like object to wrap the functionality of
+        """
+        self.wsgi_input = wsgi_input
+        self.bytes_received = 0
+        self.client_disconnect = False
+
+    def read(self, *args, **kwargs):
+        """
+        Pass read request to the underlying file-like object and
+        add bytes read to total.
+        """
+        try:
+            chunk = self.wsgi_input.read(*args, **kwargs)
+        except Exception:
+            self.client_disconnect = True
+            raise
+        self.bytes_received += len(chunk)
+        return chunk
+
+    def readline(self, *args, **kwargs):
+        """
+        Pass readline request to the underlying file-like object and
+        add bytes read to total.
+        """
+        try:
+            line = self.wsgi_input.readline(*args, **kwargs)
+        except Exception:
+            self.client_disconnect = True
+            raise
+        self.bytes_received += len(line)
+        return line