How can I selectively mask arbitrary data being sent over an insecure link?

Question

I'm using an offsite error logging package for my python web application. When I send an error I include the contents of (among other things) the POST variable and some template data. Some of this data must not be sent to the error logging service (passwords, some other template data).

How can I take a payload that consists of a mix of data -- objects, dicts, et al -- and mask out (say) every field or entry named my_private_data?

What I'd expect is that if an object has a string or integer property (the private data will always be a number or a string) my_private_data=SOME SECRET, it would be transmitted as my_private_data=**********

How do I accomplish this?

Answer 1

If you have the POST data as a string, you can use the standard modules "urlparse" and "urllib" to remove certain parameters:

import urlparse
import urllib

postDataAsDict = urlparse.parse_qs("a=5&b=3&c=%26escaped", strict_parsing = True)
print postDataAsDict # prints {'a': ['5'], 'b': ['3'], 'c': ['&escaped']}

del postDataAsDict["a"] # in your case "my_private_data"
print urllib.urlencode(postDataAsDict, True) # prints c=%26escaped&b=3

Note that parse_qs correctly supports multiple parameters that have the same name, so don't worry about that.