Last year Google has updated their contact API usage and asked API users to allow the data sharing as Google Does. Here is Official statement from Google Contact API terms and condition page
Google supports data portability. By accessing Content through the Contacts Data API or Portable Contacts API for use in your service or application, you are agreeing to enable your users to export their contacts data to other services or applications of their choice in a way that’s substantially as fast and easy as exporting such data from Google Contacts, subject to applicable laws.
However this does not mean that we can not add our Gmail Friends to Facebook. Facebook users can use “Find Your Gmail Friends on Facebook” url to add their Gmail Friends in Facebook. For adding Gmail contacts in Facebook follow these simple steps :
First we need to export the Gmail contacts. To export Gmail Contacts please follow steps mentioned below :
- Sign in to Gmail.
- Click Contacts along the side of any Gmail page.
- From the More actions drop-down menu, select Export….
- Choose whether to export all contacts or only one group.
- Select the format in which you’d like to export your contacts’ information. Please note, some of these formats can lose some contact information.
- To transfer contacts between Google accounts, use the Google CSV format. This is the recommended way to back up your Google Contacts.
- To transfer contacts to Outlook, Yahoo! Mail, Hotmail, or various other apps, use the Outlook CSV format.
- To transfer contacts to Apple Address Book, use the vCard format.
Now login into Facebook and go to “Find Your Gmail Friends on Facebook” page and Upload your ‘google.csv’ file to Facebook using the uploader .