来自Opencensus图书馆的Golang供应商问题

I'm having problem while vendoring my go-project. Tried with both glide and go-dep - getting same problem.

$ go get -u go.opencensus.io gives the following error:

package go.opencensus.io/opencensus-go: unrecognized import path "go.opencensus.io/opencensus-go" (https fetch: Get https://go.opencensus.io/opencensus-go?go-get=1: dial tcp <some-ip>: i/o timeout)

Github link of this package - https://github.com/census-instrumentation/opencensus-go

Tried setting a proxy to shell

export http_proxy=http://104.248.231.49:8080/
export https_proxy=http://104.248.231.49:8080/

And then it worked.