Use different copies of 10-kubeadm.conf depending on version.

For kubeadm 1.8, we changed the flags we want to start kubelet with.
This change breaks 10-kubeadm.conf into two files (pre- and post-1.8)
and selects which one to use at build time, based on the target version.

I've also included unit tests for the new functionality which aren't run
by default ("go test" manually), but are meant to demonstrate the
versioning edge cases I tested.

A similar change still needs to happen for our rpm build scripts.

kubernetes/kubeadm#442

debian/Dockerfile

@@ -12,6 +12,7 @@ RUN export DEBIAN_FRONTEND=noninteractive \
     && apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
 ADD . /src
+ADD vendor /go/src
 
 WORKDIR /src
 

debian/build.go

@@ -12,6 +12,8 @@ import (
 	"strings"
 	"text/template"
 	"time"
+
+	"github.com/blang/semver"
 )
 
 type ChannelType string
@@ -41,6 +43,7 @@ type version struct {
 	Channel                             ChannelType
 	GetVersion                          func() (string, error)
 	GetDownloadLinkBase                 func(v version) (string, error)
+	KubeadmKubeletConfigFile            string
 }
 
 type cfg struct {
@@ -268,6 +271,26 @@ func getReleaseDownloadLinkBase(v version) (string, error) {
 	return fmt.Sprintf("https://dl.k8s.io/v%s", v.Version), nil
 }
 
+// The version of this file to use changed in 1.8, so use the target build
+// version to figure out which copy of it to include in the deb.
+func getKubeadmKubeletConfigFile(v version) (string, error) {
+	sv, err := semver.Make(v.Version)
+	if err != nil {
+		return "", err
+	}
+
+	v180, err := semver.Make("1.8.0-alpha.0")
+	if err != nil {
+		return "", err
+	}
+
+	if sv.GTE(v180) {
+		return "post-1.8/10-kubeadm.conf", nil
+	} else {
+		return "pre-1.8/10-kubeadm.conf", nil
+	}
+}
+
 func main() {
 	flag.Parse()
 
@@ -437,6 +460,12 @@ func main() {
 			c.DebArch = c.Arch
 		}
 
+		var err error
+		c.KubeadmKubeletConfigFile, err = getKubeadmKubeletConfigFile(v)
+		if err != nil {
+			log.Fatalf("error getting kubeadm config: %v", err)
+		}
+
 		return c.run()
 	}); err != nil {
 		log.Fatalf("err: %v", err)

debian/build_test.go

@@ -0,0 +1,71 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestGetKubeadmConfig(t *testing.T) {
+	testcases := []struct {
+		version      string
+		expectConfig string
+		expectErr    bool
+	}{
+		{
+			"1.6.10",
+			"pre-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.7.10",
+			"pre-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.7.0-beta.5",
+			"pre-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.8.0",
+			"post-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.8.0-alpha.0",
+			"post-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.8.0-beta.2",
+			"post-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"1.9.0",
+			"post-1.8/10-kubeadm.conf",
+			false,
+		},
+		{
+			"not-a-real-version",
+			"",
+			true,
+		},
+	}
+
+	for _, tc := range testcases {
+		v := version{
+			Version: tc.version,
+		}
+		kubeadmConfig, err := getKubeadmConfig(v)
+
+		if err != nil {
+			if !tc.expectErr {
+				t.Errorf("getKubeadmConfig(%s) returned unwanted error: %v", tc.version, err)
+			}
+		} else {
+			if kubeadmConfig != tc.expectConfig {
+				t.Errorf("getKubeadmConfig(%s) got %q, wanted %q", tc.version, kubeadmConfig, tc.expectConfig)
+			}
+		}
+	}
+}

debian/xenial/kubeadm/channel/nightly/etc/systemd/system/kubelet.service.d/post-1.8/10-kubeadm.conf

@@ -0,0 +1 @@
+../../../../../../stable/etc/systemd/system/kubelet.service.d/post-1.8/10-kubeadm.conf

debian/xenial/kubeadm/channel/nightly/etc/systemd/system/kubelet.service.d/pre-1.8/10-kubeadm.conf

@@ -0,0 +1 @@
+../../../../../../stable/etc/systemd/system/kubelet.service.d/pre-1.8/10-kubeadm.conf

debian/xenial/kubeadm/channel/stable/etc/systemd/system/kubelet.service.d/post-1.8/10-kubeadm.conf

@@ -0,0 +1,10 @@
+[Service]
+Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf"
+Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
+Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
+Environment="KUBELET_DNS_ARGS=--cluster-dns=10.96.0.10 --cluster-domain=cluster.local"
+Environment="KUBELET_AUTHZ_ARGS=--authorization-mode=Webhook --client-ca-file=/etc/kubernetes/pki/ca.crt"
+Environment="KUBELET_CADVISOR_ARGS=--cadvisor-port=0"
+Environment="KUBELET_CERTIFICATE_ARGS=--rotate-certificates=true"
+ExecStart=
+ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_AUTHZ_ARGS $KUBELET_CADVISOR_ARGS $KUBELET_CERTIFICATE_ARGS $KUBELET_EXTRA_ARGS

debian/xenial/kubeadm/channel/unstable/etc/systemd/system/kubelet.service.d/post-1.8/10-kubeadm.conf

@@ -0,0 +1 @@
+../../../../../../stable/etc/systemd/system/kubelet.service.d/post-1.8/10-kubeadm.conf

debian/xenial/kubeadm/channel/unstable/etc/systemd/system/kubelet.service.d/pre-1.8/10-kubeadm.conf

@@ -0,0 +1 @@
+../../../../../../stable/etc/systemd/system/kubelet.service.d/pre-1.8/10-kubeadm.conf

debian/xenial/kubeadm/debian/kubeadm.install

@@ -1,2 +1,2 @@
 usr/bin/kubeadm usr/bin/
-channel/{{ .Channel }}/etc/systemd/system/kubelet.service.d/10-kubeadm.conf etc/systemd/system/kubelet.service.d/
+channel/{{ .Channel }}/etc/systemd/system/kubelet.service.d/{{ .KubeadmKubeletConfigFile }} etc/systemd/system/kubelet.service.d/