pkg/ipnet: Provide an IPNet structure with CIDR serialization

installer/pkg/config-generator/BUILD.bazel

@@ -13,6 +13,7 @@ go_library(
         "//installer/pkg/config:go_default_library",
         "//installer/pkg/copy:go_default_library",
         "//pkg/asset/tls:go_default_library",
+        "//pkg/ipnet:go_default_library",
         "//pkg/types:go_default_library",
         "//vendor/github.com/apparentlymart/go-cidr/cidr:go_default_library",
         "//vendor/github.com/coreos/ignition/config/v2_2:go_default_library",
@@ -37,5 +38,6 @@ go_test(
     deps = [
         "//installer/pkg/config:go_default_library",
         "//pkg/asset/tls:go_default_library",
+        "//vendor/github.com/stretchr/testify/assert:go_default_library",
     ],
 )

installer/pkg/config-generator/fixtures/kube-system.yaml

@@ -31,12 +31,8 @@ data:
       creationTimestamp: null
       name: test
     networking:
-      podCIDR:
-        IP: 10.2.0.0
-        Mask: //8AAA==
-      serviceCIDR:
-        IP: 10.3.0.0
-        Mask: //8AAA==
+      podCIDR: 10.2.0.0/16
+      serviceCIDR: 10.3.0.0/16
       type: canal
     platform:
       aws:

installer/pkg/config-generator/generator.go

@@ -19,6 +19,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	"github.com/openshift/installer/installer/pkg/config"
+	"github.com/openshift/installer/pkg/ipnet"
 	"github.com/openshift/installer/pkg/types"
 )
 
@@ -185,8 +186,8 @@ func (c *ConfigGenerator) installConfig() (*types.InstallConfig, error) {
 		PullSecret: c.PullSecret,
 		Networking: types.Networking{
 			Type:        types.NetworkType(string(c.Networking.Type)),
-			ServiceCIDR: *serviceCIDR,
-			PodCIDR:     *podCIDR,
+			ServiceCIDR: ipnet.IPNet{IPNet: *serviceCIDR},
+			PodCIDR:     ipnet.IPNet{IPNet: *podCIDR},
 		},
 		Platform: platform,
 		Machines: []types.MachinePool{{

installer/pkg/config-generator/generator_test.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/openshift/installer/installer/pkg/config"
 	"github.com/openshift/installer/pkg/asset/tls"
+	"github.com/stretchr/testify/assert"
 )
 
 func initConfig(t *testing.T, file string) ConfigGenerator {
@@ -46,9 +47,7 @@ func TestUrlFunctions(t *testing.T) {
 		},
 	}
 	for _, tc := range testCases {
-		if tc.got != tc.expected {
-			t.Errorf("Test case %s: expected: %s, got: %s", tc.test, tc.expected, tc.got)
-		}
+		assert.Equal(t, tc.expected, tc.got)
 	}
 }
 
@@ -68,9 +67,7 @@ func TestGetEtcdServersURLs(t *testing.T) {
 
 		config := initConfig(t, tc.configFile)
 		got := config.getEtcdServersURLs()
-		if got != tc.expected {
-			t.Errorf("Test case %s: expected: %s, got: %s", tc.test, tc.expected, got)
-		}
+		assert.Equal(t, tc.expected, got)
 	}
 }
 
@@ -85,9 +82,7 @@ func TestKubeSystem(t *testing.T) {
 		t.Errorf("Test case TestKubeSystem: failed to ReadFile(): %s", err)
 	}
 
-	if got != string(expected) {
-		t.Errorf("Test case TestKubeSystem: expected: %s, got: %s", expected, got)
-	}
+	assert.Equal(t, string(expected), got)
 }
 
 func TestCIDRHost(t *testing.T) {
@@ -115,9 +110,7 @@ func TestCIDRHost(t *testing.T) {
 		if err != nil {
 			t.Errorf("Test case %s: failed to run cidrhost(): %s", tc.test, err)
 		}
-		if got != tc.expected {
-			t.Errorf("Test case %s: expected: %s, got: %s", tc.test, tc.expected, got)
-		}
+		assert.Equal(t, tc.expected, got)
 	}
 }
 

pkg/asset/installconfig/installconfig_test.go

@@ -163,12 +163,8 @@ metadata:
   creationTimestamp: null
   name: test-cluster-name
 networking:
-  podCIDR:
-    IP: ""
-    Mask: null
-  serviceCIDR:
-    IP: ""
-    Mask: null
+  podCIDR: null
+  serviceCIDR: null
   type: ""
 platform:
 %s

pkg/asset/tls/helper.go

@@ -53,7 +53,7 @@ func genDNSNamesForAPIServerCertKey(cfg *types.InstallConfig) ([]string, error)
 }
 
 func genIPAddressesForAPIServerCertKey(cfg *types.InstallConfig) ([]net.IP, error) {
-	apiServerAddress, err := cidrhost(cfg.Networking.ServiceCIDR, 1)
+	apiServerAddress, err := cidrhost(cfg.Networking.ServiceCIDR.IPNet, 1)
 	if err != nil {
 		return nil, err
 	}
@@ -72,7 +72,7 @@ func genDNSNamesForOpenshiftAPIServerCertKey(cfg *types.InstallConfig) ([]string
 }
 
 func genIPAddressesForOpenshiftAPIServerCertKey(cfg *types.InstallConfig) ([]net.IP, error) {
-	apiServerAddress, err := cidrhost(cfg.Networking.ServiceCIDR, 1)
+	apiServerAddress, err := cidrhost(cfg.Networking.ServiceCIDR.IPNet, 1)
 	if err != nil {
 		return nil, err
 	}

pkg/ipnet/BUILD.bazel

@@ -0,0 +1,14 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["ipnet.go"],
+    importpath = "github.com/openshift/installer/pkg/ipnet",
+    visibility = ["//visibility:public"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["ipnet_test.go"],
+    embed = [":go_default_library"],
+)

pkg/ipnet/ipnet.go

@@ -0,0 +1,49 @@
+// Package ipnet wraps net.IPNet to get CIDR serialization.
+package ipnet
+
+import (
+	"encoding/json"
+	"net"
+	"reflect"
+)
+
+var nullString = "null"
+var nullBytes = []byte(nullString)
+var emptyIPNet = net.IPNet{}
+
+// IPNet wraps net.IPNet to get CIDR serialization.
+type IPNet struct {
+	net.IPNet
+}
+
+// MarshalJSON interface for an IPNet
+func (ipnet IPNet) MarshalJSON() (data []byte, err error) {
+	if reflect.DeepEqual(ipnet.IPNet, emptyIPNet) {
+		return nullBytes, nil
+	}
+
+	return json.Marshal(ipnet.String())
+}
+
+// UnmarshalJSON interface for an IPNet
+func (ipnet *IPNet) UnmarshalJSON(b []byte) (err error) {
+	if string(b) == nullString {
+		ipnet.IP = net.IP{}
+		ipnet.Mask = net.IPMask{}
+		return nil
+	}
+
+	var cidr string
+	err = json.Unmarshal(b, &cidr)
+	if err != nil {
+		return err
+	}
+
+	ip, net, err := net.ParseCIDR(cidr)
+	if err != nil {
+		return err
+	}
+	ipnet.IP = ip
+	ipnet.Mask = net.Mask
+	return nil
+}

pkg/ipnet/ipnet_test.go

@@ -0,0 +1,62 @@
+package ipnet
+
+import (
+	"encoding/json"
+	"net"
+	"testing"
+)
+
+func assertJSON(t *testing.T, data interface{}, expected string) {
+	actualBytes, err := json.Marshal(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	actual := string(actualBytes)
+
+	if actual != expected {
+		t.Fatalf("%s != %s", actual, expected)
+	}
+}
+
+func TestMarshal(t *testing.T) {
+	stdlibIPNet := &net.IPNet{
+		IP:   net.IP{192, 168, 0, 10},
+		Mask: net.IPv4Mask(255, 255, 255, 0),
+	}
+	assertJSON(t, stdlibIPNet, "{\"IP\":\"192.168.0.10\",\"Mask\":\"////AA==\"}")
+	wrappedIPNet := &IPNet{IPNet: *stdlibIPNet}
+	assertJSON(t, wrappedIPNet, "\"192.168.0.10/24\"")
+	assertJSON(t, &IPNet{}, "null")
+	assertJSON(t, nil, "null")
+}
+
+func TestUnmarshal(t *testing.T) {
+	for _, ipNetIn := range []*IPNet{
+		nil,
+		{IPNet: net.IPNet{
+			IP:   net.IP{192, 168, 0, 10},
+			Mask: net.IPv4Mask(255, 255, 255, 0),
+		}},
+	} {
+		data, err := json.Marshal(ipNetIn)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		t.Run(string(data), func(t *testing.T) {
+			var ipNetOut *IPNet
+			err := json.Unmarshal(data, &ipNetOut)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if ipNetIn == nil {
+				if ipNetOut != nil {
+					t.Fatalf("%v != %v", ipNetOut, ipNetIn)
+				}
+			} else if ipNetOut.String() != ipNetIn.String() {
+				t.Fatalf("%v != %v", ipNetOut, ipNetIn)
+			}
+		})
+	}
+}

pkg/types/BUILD.bazel

@@ -9,5 +9,8 @@ go_library(
     ],
     importpath = "github.com/openshift/installer/pkg/types",
     visibility = ["//visibility:public"],
-    deps = ["//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library"],
+    deps = [
+        "//pkg/ipnet:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+    ],
 )

pkg/types/installconfig.go

@@ -3,6 +3,7 @@ package types
 import (
 	"net"
 
+	"github.com/openshift/installer/pkg/ipnet"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -58,8 +59,8 @@ type Platform struct {
 // Networking defines the pod network provider in the cluster.
 type Networking struct {
 	Type        NetworkType `json:"type"`
-	ServiceCIDR net.IPNet   `json:"serviceCIDR"`
-	PodCIDR     net.IPNet   `json:"podCIDR"`
+	ServiceCIDR ipnet.IPNet `json:"serviceCIDR"`
+	PodCIDR     ipnet.IPNet `json:"podCIDR"`
 }
 
 // NetworkType defines the pod network provider in the cluster.