In my site, I am using authentication based on OpenID. I am requesting 'email address' from the OpenID provider. The problem is each provider is sending the email address in their own parameter in GET response after authentication. I am listing down three of what I have seen
StackExchange
openid_alias3_value_alias1
Yahoo!
openid_ax_value_email
openid_ext1_value_email
It is difficult (and not standard) to write separate lines of code for each OpenID provider. Is there a standard for this?
(added a bug : https://meta.stackexchange.com/questions/106922/stackexchange-openid-parameter-for-email-should-be-openid-ax-value-email)