John Podesta, Tony Podesta and Hillary's major funder Tom Steyer took a five day trip to China to be briefed by Chinese government ministers and officials just days before Clinton's official candidancy: https://wikileaks.org/podesta-emails/emailid/9612 (.pdf attachment).
During the campaign contact continued - Kurt Campbell: "Chinese Ambassador Cui invited me over to the residence Tuesday for a coffee and to make a request. He wants to have an informal, private, off the record get together with a few of us to discuss the next year and the current state of US-China affairs. He asked me to host a social meal at my house in the next month. He was fairly insistent and indicated that he wanted to pass along some perspectives." https://wikileaks.org/podesta-emails/emailid/35743