Last year, we added support for OAuth 1.0 – a much better way to have your users authenticating against Flickr. More information on Flickr user authentication via this method is available here in our Developer Guide and specifically here.
If you are app already uses OAuth, then you can skip this post and look at some gorgeous photos instead. However – if your app still uses the old Authentication API, you will need to update it to OAuth by July 31st this year.
Updating to OAuth is easy and you don’t worry about any user impact. You can exchange an old auth token from the old Authentication API, to an OAuth access token. The process simply requires that you make an authenticated request to the flickr.auth.oauth.getAccessToken API, which will exchange the old token used to make the request, with a new OAuth access token. Again, everything is documented right here. Flickr member Jef Poskanzer has also written an overview and comparison between the two auth methods: http://acme.com/flickr/authmap.html.
After July 31st, we will no longer support the old Authentication API.
Thanks for making Flickr more fun by contributing to our growing collection of apps!
Your Engineering Team at Flickr