rancher: Rancher agent does not use proxy environment in callback to rancher

What kind of request is this (question/bug/enhancement/feature request): Bug

Steps to reproduce (least amount of steps as possible): Import existing cluster into Rancher - with a proxy between that cluster and Rancher. Add to the agent yaml the required HTTP_PROXY, HTTPS_PROXY, NO_PROXY envs

Expected : Rancher cluster/node can contact Rancher and import is successful

Result: Rancher agent wss calls fail, log time=“2019-12-19T09:39:08Z” level=info msg=“Connecting to wss://rancher.foobar.com with token $token” time=“2019-12-19T09:39:08Z” level=info msg=“Connecting to proxy” url=“wss://rancher.foobar.com/v3/connect/register” time=“2019-12-19T09:39:18Z” level=error msg=“Failed to connect to proxy. Empty dialer response” error=“dial tcp :443: i/o timeout” time=“2019-12-19T09:39:18Z” level=error msg=“Remotedialer proxy error” error=“dial tcp $IP_OF_RANCHER:443: i/o timeout”

Other details that may be helpful: This is the same issue as rancher/rancher#24681 and rancher/rancher#22750 , sorry for opening a new one, but those are probably not clear enough. The problem is in remotedialer/client.go line 26 dialer = &websocket.Dialer{HandshakeTimeout:HandshakeTimeOut} should read instead dialer = &websocket.Dialer{HandshakeTimeout:HandshakeTimeOut,Proxy: http.ProxyFromEnvironment}

Environment information

• Rancher version (rancher/rancher/rancher/server image tag or shown bottom left in the UI): 2.3.3 single install

gz#13523