GitHub doesn't select Primary Email

[abourget]

I've got 7 emails in my GitHub account.. but I selected one as my primary. python-social-auth just takes the first one in the provided list, disregarding my selection. I have stale e-mails in there.. Think we could pick the primary e-mail!

This was an attempt to monkey patch django-social-auth with the intended behavior. If there's interest, I can make it a PR in python-social-auth:

# re-implements: backends/contrib/github.py:L57-66
def _fetch_emails_replacement(self, access_token):
    """Fetch private emails from Github account

    Github returns something like:

    [
      {
        "email": "octocat@github.com",
        "verified": true,
        "primary": true
      }
    ]

    """
    url = GITHUB_USER_DATA_URL + '/emails?' + urlencode({
        'access_token': access_token
    })

    try:
        data = simplejson.load(dsa_urlopen(url))
    except (ValueError, HTTPError):
        return []

    emails = [x['email'] for x in data
              if x['primary']]
    if emails:
        return [emails[0]]
    else:
        if data:
            return [data[0]['email']]
        else:
            return []

github.GithubBackend._fetch_emails = _fetch_emails_replacement

[omab]

I've introduced a change to give github primary emails priority.