如何在yocto食谱中管理golang项目的外部依赖关系

I want to write a yocto recipe for a cross-compiled golang application with Yocto 2.4.1 but I cannot get external dependencies to work. Can anyone help me?

current RECIPE_FILE: hello-world_%.bb
LICENSE = "CLOSED"
LIC_FILES_CHKSUM = ""
DESCRIPTION = "Hello world test with golang."

inherit go

COMPATIBLE_MACHINE = "(<machine>)"
DEPENDS = "go-cross-${TARGET_ARCH}"
GO_IMPORT = "hello-world"
SRC_URI = "<git_url>/${GO_IMPORT}.git;branch=${SRCBRANCH};tag=${PV}" 
SRCBRANCH = "master"
PV = "0.01"
S = "${WORKDIR}/git"

do_compile() {
  export GOPATH="${WORKDIR}/build"
  export GOARCH="<machine_arch>"
  export GOOS="linux"
  export CGO_ENABLED="0"
  go build src/${GO_IMPORT}/hello-world.go
}

 do_install() {
   install -d "${D}/${bindir}"
   install -m 0755 "${WORKDIR}/build/hello-world" "${D}/${bindir}/hello-world"
 }

RDEPENDS_${PN}-dev += "bash"

This recipe works fine for internal dependencies only. But how do I integrate external dependencies like "github.com/golang/protobuf/ptypes"?

PROJECT_FILE: hello-world.go

package main

import (
    "fmt"
    "github.com/golang/protobuf/ptypes"
)

func main() {
    timestamp := ptypes.TimestampNow()
    fmt.Println(timestamp)
}

Does anyone knows a solution for this use case?

Or does anyone know how "go-dep" could handle this?

Best regards