Hash function that produces short hashes?

Question

Is there a way of encryption that can take a string of any length and produce a sub-10-character hash? I want to produce reasonably unique ID\'s but based on message content

Answer 1

Just summarizing an answer that was helpful to me (noting @erasmospunk's comment about using base-64 encoding). My goal was to have a short string that was mostly unique...

I'm no expert, so please correct this if it has any glaring errors (in Python again like the accepted answer):

import base64
import hashlib
import uuid

unique_id = uuid.uuid4()
# unique_id = UUID('8da617a7-0bd6-4cce-ae49-5d31f2a5a35f')

hash = hashlib.sha1(str(unique_id).encode("UTF-8"))
# hash.hexdigest() = '882efb0f24a03938e5898aa6b69df2038a2c3f0e'

result = base64.b64encode(hash.digest())
# result = b'iC77DySgOTjliYqmtp3yA4osPw4='

The result here is using more than just hex characters (what you'd get if you used hash.hexdigest()) so it's less likely to have a collision (that is, should be safer to truncate than a hex digest).

Note: Using UUID4 (random). See http://en.wikipedia.org/wiki/Universally_unique_identifier for the other types.