Add Python3 compatibility

UniversalAnalytics/HTTPLog.py

@@ -1,24 +1,47 @@
 #!/usr/bin/python
+
 ###############################################################################
+#
 # Formatting filter for urllib2's HTTPHandler(debuglevel=1) output
 # Copyright (c) 2013, Analytics Pros
-# 
-# This project is free software, distributed under the BSD license. 
-# Analytics Pros offers consulting and integration services if your firm needs 
+#
+# This project is free software, distributed under the BSD license.
+# Analytics Pros offers consulting and integration services if your firm needs
 # assistance in strategy, implementation, or auditing existing work.
+#
 ###############################################################################
 
+# Standard library imports
+from __future__ import division, print_function, with_statement
+import re
+import sys
 
-import sys, re, os
-from cStringIO import StringIO
-
+# Third party libraries
+from six.moves import cStringIO as StringIO  # Used by tests
+import six
 
 
 class BufferTranslator(object):
-    """ Provides a buffer-compatible interface for filtering buffer content.
+    """
+    Provides a buffer-compatible interface for filtering buffer content.
     """
     parsers = []
 
+    @staticmethod
+    def stripslashes(content):
+        if six.PY3:
+            content = content.encode('UTF-8')
+            return content.decode('unicode_escape')
+        else:
+            return content.decode('string_escape')
+
+    @staticmethod
+    def addslashes(content):
+        if six.PY3:
+            return content.encode('unicode_escape')
+        else:
+            return content.encode('string_escape')
+
     def __init__(self, output):
         self.output = output
         self.encoding = getattr(output, 'encoding', None)
@@ -27,56 +50,51 @@ def write(self, content):
         content = self.translate(content)
         self.output.write(content)
 
-
-    @staticmethod
-    def stripslashes(content):
-        return content.decode('string_escape')
-
-    @staticmethod
-    def addslashes(content):
-        return content.encode('string_escape')
-
     def translate(self, line):
         for pattern, method in self.parsers:
             match = pattern.match(line)
             if match:
                 return method(match)
-
         return line
-
+
+    def flush(self):
+        pass
 
 
 class LineBufferTranslator(BufferTranslator):
-    """ Line buffer implementation supports translation of line-format input
-        even when input is not already line-buffered. Caches input until newlines 
-        occur, and then dispatches translated input to output buffer.
     """
-    def __init__(self, *a, **kw):
+    Line buffer implementation supports translation of line-format input
+    even when input is not already line-buffered. Caches input until newlines
+    occur, and then dispatches translated input to output buffer.
+    """
+    def __init__(self, *args, **kwargs):
         self._linepending = []
-        super(LineBufferTranslator, self).__init__(*a, **kw)
-    
+        super(LineBufferTranslator, self).__init__(*args, **kwargs)
+
     def write(self, _input):
         lines = _input.splitlines(True)
+        last = 0
         for i in range(0, len(lines)):
             last = i
             if lines[i].endswith('\n'):
-                prefix = len(self._linepending) and ''.join(self._linepending) or ''
+                prefix = (len(self._linepending) and
+                          ''.join(self._linepending) or '')
                 self.output.write(self.translate(prefix + lines[i]))
                 del self._linepending[0:]
                 last = -1
-
-        if last >= 0:
-            self._linepending.append(lines[ last ])
 
+        if lines and last >= 0:
+            self._linepending.append(lines[last])
 
     def __del__(self):
         if len(self._linepending):
             self.output.write(self.translate(''.join(self._linepending)))
 
 
 class HTTPTranslator(LineBufferTranslator):
-    """ Translates output from |urllib2| HTTPHandler(debuglevel = 1) into
-        HTTP-compatible, readible text structures for human analysis.
+    """
+    Translates output from |urllib2| HTTPHandler(debuglevel = 1) into
+    HTTP-compatible, readible text structures for human analysis.
     """
 
     RE_LINE_PARSER = re.compile(r'^(?:([a-z]+):)\s*(\'?)([^\r\n]*)\2(?:[\r\n]*)$')
@@ -89,14 +107,13 @@ def spacer(cls, line):
         return cls.RE_PARAMETER_SPACER.sub(r' &\1= ', line)
 
     def translate(self, line):
-
         parsed = self.RE_LINE_PARSER.match(line)
 
         if parsed:
             value = parsed.group(3)
             stage = parsed.group(1)
 
-            if stage == 'send': # query string is rendered here
+            if stage == 'send':  # query string is rendered here
                 return '\n# HTTP Request:\n' + self.stripslashes(value)
             elif stage == 'reply':
                 return '\n\n# HTTP Response:\n' + self.stripslashes(value)
@@ -105,17 +122,17 @@ def translate(self, line):
             else:
                 return value
 
-
         return line
 
 
-def consume(outbuffer = None): # Capture standard output
+def consume(outbuffer=None):
+    """
+    Capture standard output.
+    """
     sys.stdout = HTTPTranslator(outbuffer or sys.stdout)
     return sys.stdout
 
 
 if __name__ == '__main__':
     consume(sys.stdout).write(sys.stdin.read())
-    print '\n'
-
-# vim: set nowrap tabstop=4 shiftwidth=4 softtabstop=0 expandtab textwidth=0 filetype=python foldmethod=indent foldcolumn=4
+    print('\n')