Here you are:
https://theintercept.com/2016/08/06/accusing-wikileaks-bias-...
People talk a lot about how Putin is an opportunist. I think he saw how bitter Assange was becoming and understood if he gave him the documents, he could step back and let him carry out his vengeance against a woman who had a huge role in forcing him to ground in the embassy ("can't we just drone this guy?"). I'm told this is a Rule of Power. But that is speculation.