Description:
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When used as part of mod_php in Apache, the OAuthProvider class does not honour the "Authorization" header if the name does not match exactly. Requests made via python-oauth2 (http://github.com/simplegeo/python-oauth2) via httplib2 normalise request headers to be all lowercase, which means that the credentials are not picked up.

According to HTTP 1.1 (RFC2616 section 4.2), header names should be case-insensitive.

Reproduce code:
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Reproduce:

Use pycloc (http://github.com/dingram/pycloc) to make a PUT request against an OAuthProvider endpoint. The credentials will be placed in an "authorization:" header. Example request:

pycloc http://localhost/oauth/a_private_api.php -B blah=foo -u


Patch against SVN HEAD (r301479):

http://www.dmi.me.uk/code/patches/oauth-provider-case-insensitive-header.patch

Expected result:
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Expected result is for the request to succeed, and for the authorization header to be correctly parsed, whatever capitalisation it has.

Actual result:
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OAuthProvider throws an exception when it cannot access the header.

Exception: exception 'OAuthException' with message 'Missing required parameters' in /var/www/localhost/htdocs/oauth/a_private_api.php:15
Stack trace:
#0 /var/www/localhost/htdocs/oauth/a_private_api.php(15): OAuthProvider->checkOAuthRequest()
#1 {main}