build: use Go 1.15

Signed-off-by: Pires <pjpires@gmail.com>

.circleci/config.yml

@@ -3,7 +3,7 @@ jobs:
   validate:
     resource_class: xlarge
     docker:
-      - image: circleci/golang:1.13
+      - image: circleci/golang:1.15
         environment:
           GO111MODULE: "on"
           GOPROXY: https://proxy.golang.org
@@ -30,7 +30,7 @@ jobs:
   test:
     resource_class: xlarge
     docker:
-      - image: circleci/golang:1.13
+      - image: circleci/golang:1.15
         environment:
           GO111MODULE: "on"
     working_directory: /go/src/github.com/virtual-kubelet/virtual-kubelet
@@ -114,7 +114,7 @@ jobs:
           command: |
             mkdir $HOME/.go
             export PATH=$HOME/.go/bin:${PATH}
-            curl -fsSL -o "/tmp/go.tar.gz" "https://dl.google.com/go/go1.13.12.linux-amd64.tar.gz"
+            curl -fsSL -o "/tmp/go.tar.gz" "https://dl.google.com/go/go1.15.6.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:1.13 as builder
+FROM golang:1.15 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.go1.13
+goimports := golang.org/x/tools/cmd/goimports@release-branch.go1.15
 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 1.13
+go 1.15
 
 require (
 	contrib.go.opencensus.io/exporter/jaeger v0.1.0