upgrade to go 1.13

required by k8s libs at 1.18

.circleci/config.yml

@@ -3,7 +3,7 @@ jobs:
   validate:
     resource_class: xlarge
     docker:
-      - image: circleci/golang:1.12
+      - image: circleci/golang:1.13
         environment:
           GO111MODULE: "on"
           GOPROXY: https://proxy.golang.org
@@ -33,7 +33,7 @@ jobs:
   test:
     resource_class: xlarge
     docker:
-      - image: circleci/golang:1.12
+      - image: circleci/golang:1.13
         environment:
           GO111MODULE: "on"
     working_directory: /go/src/github.com/virtual-kubelet/virtual-kubelet
@@ -117,7 +117,7 @@ jobs:
           command: |
             mkdir $HOME/.go
             export PATH=$HOME/.go/bin:${PATH}
-            curl -fsSL -o "/tmp/go.tar.gz" "https://dl.google.com/go/go1.12.6.linux-amd64.tar.gz"
+            curl -fsSL -o "/tmp/go.tar.gz" "https://dl.google.com/go/go1.13.12.linux-amd64.tar.gz"
             tar -C $HOME/.go --strip-components=1 -xzf "/tmp/go.tar.gz"
             go version
             make e2e

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.12 as builder
+FROM golang:1.13 as builder
 ENV PATH /go/bin:/usr/local/go/bin:$PATH
 ENV GOPATH /go
 COPY . /go/src/github.com/virtual-kubelet/virtual-kubelet

Makefile

@@ -13,7 +13,7 @@ include Makefile.e2e
 # Also, we will want to lock our tool versions using go mod:
 # https://github.com/golang/go/wiki/Modules#how-can-i-track-tool-dependencies-for-a-module
 gobin_tool ?= $(shell which gobin || echo $(GOPATH)/bin/gobin)
-goimports := golang.org/x/tools/cmd/goimports@release-branch.go1.12
+goimports := golang.org/x/tools/cmd/goimports@release-branch.go1.13
 gocovmerge := github.com/wadey/gocovmerge@b5bfa59ec0adc420475f97f89b58045c721d761c
 goreleaser := github.com/goreleaser/goreleaser@v0.82.2
 gox := github.com/mitchellh/gox@v1.0.1

go.mod

@@ -1,6 +1,6 @@
 module github.com/virtual-kubelet/virtual-kubelet
 
-go 1.12
+go 1.13
 
 require (
 	contrib.go.opencensus.io/exporter/jaeger v0.1.0