Tuesday, January 15, 2013

python httplib2 7.x and ssl

this is not a completely new issue, and the internet helped me find the solution in about 5 minutes, but it was not very clear or obvious so I thought I'd write it down succinctly for posterity:

Python's httplib2 package did not validate ssl certificates in versions < 7.0, and started to from 7.0 and up. Unfortunately, it ships with its own set of trusted ssl certificates which comprise only a medium-sized subset of all of your favorite sites' certs (for instance, wikipedia fails when pinged at https://en.wikipedia.org!). The error looks like this:

  File "/home/deploy/.virtualenvs/sandbox.koaladeal.com/local/lib/python2.7/site-packages/httplib2/__init__.py", line 1597, in request
    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)

  File "/home/deploy/.virtualenvs/sandbox.koaladeal.com/local/lib/python2.7/site-packages/httplib2/__init__.py", line 1345, in _request
    (response, content) = self._conn_request(conn, request_uri, method, body, headers)

  File "/home/deploy/.virtualenvs/sandbox.koaladeal.com/local/lib/python2.7/site-packages/httplib2/__init__.py", line 1281, in _conn_request

  File "/home/deploy/.virtualenvs/sandbox.koaladeal.com/local/lib/python2.7/site-packages/httplib2/__init__.py", line 1036, in connect
    raise SSLHandshakeError(e)

SSLHandshakeError: [Errno 1] _ssl.c:504: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed

 So the solution is to use ubuntu's system default cert file, which lives at /etc/ssl/certs/ca-certificates.crt. I ended up overwriting the one that shipped with httplib2, which fixes the problem globally, but fails if we ever reinstall httplib2. Hence this blog post for posterity. If anyone knows of another way to globally install a new certificates file for httplib2 without changing the package itself, I'm all ears. I might just onboard the package to our project (but then I have to remember never to pip install it...).

by the way, this page was most helpful.

facepalms: 3