module UsersHelper
	def gravatar_for(user,options={size:50})
		# unique photo for every name
		size = options[:size]
		gravatar_id = Digest::MD5::hexdigest(user.email.downcase)
		gravatar_url = "https://secure.gravatar.com/avatar/#{gravatar_id}?s=#{size}"
		image_tag(gravatar_url, alt: user.name, class: "gravatar")
	end
end
