Fix up migration output and its docs

Signed-off-by: JoshVanL <vleeuwenjoshua@gmail.com>

docs/tasks/upgrading/upgrading-0.10-0.11.rst

@@ -53,8 +53,8 @@ A full table of annotations, including the old and new equivalents:
 | certmanager.k8s.io/acme-http01-ingress-class | acme.cert-manager.io/http01-ingress-class |
 | certmanager.k8s.io/issuer                    | cert-manager.io/issuer                    |
 | certmanager.k8s.io/cluster-issuer            | cert-manager.io/cluster-issuer            |
-| certmanager.k8s.io/acme-challenge-type       | DEPRECIATED                               |
-| certmanager.k8s.io/acme-dns01-provider       | DEPRECIATED                               |
+| certmanager.k8s.io/acme-challenge-type       | DEPRECATED                                |
+| certmanager.k8s.io/acme-dns01-provider       | DEPRECATED                                |
 | certmanager.k8s.io/alt-names                 | cert-manager.io/alt-names                 |
 | certmanager.k8s.io/ip-sans                   | cert-manager.io/ip-sans                   |
 | certmanager.k8s.io/common-name               | cert-manager.io/common-name               |
@@ -84,13 +84,13 @@ your cluster for you.
    $ TODO: Add link
 
    # Mark the binary as executable and run the binary against your cluster
-   $ chmod +x api-migration && ./api-migration --kubeconfig /path/to/my/kubeconfig
+   $ chmod +x api-migration && ./api-migration --kubeconfig /path/to/my/kubeconfig.yaml
 
    # Follow the CLI ouput and check for the difference that has been made in files
-   $ vim -d ingress.yaml ingress-migrated.yaml
+   $ diff ingress.yaml ingress-migrated.yaml
 
    # Finally, once the new ingress resources have been reviewed, apply the manifests
-   $ kubectl apply -f ingress-migrated --kubeconfig /path/to/my/kubeconfig
+   $ kubectl apply -f ingress-migrated --kubeconfig /path/to/my/kubeconfig.yaml
 
 You should make sure to update _all_ Ingress resources to ensure that your
 certificates continue to be kept up to date.

hack/api-migration/BUILD.bazel

@@ -7,7 +7,7 @@ go_library(
     visibility = ["//visibility:private"],
     deps = [
         "@com_github_spf13_cobra//:go_default_library",
-        "@io_k8s_api//networking/v1beta1:go_default_library",
+        "@io_k8s_api//extensions/v1beta1:go_default_library",
         "@io_k8s_apimachinery//pkg/apis/meta/v1:go_default_library",
         "@io_k8s_apimachinery//pkg/runtime/serializer/json:go_default_library",
         "@io_k8s_client_go//kubernetes:go_default_library",

hack/api-migration/main.go

@@ -22,15 +22,17 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"strings"
 
 	"github.com/spf13/cobra"
-	networkingv1beta "k8s.io/api/networking/v1beta1"
+	networkingv1beta "k8s.io/api/extensions/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/serializer/json"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/client-go/tools/clientcmd"
+
 	// This package is required to be imported to register all client
 	// plugins.
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
@@ -58,7 +60,7 @@ var (
 		"certmanager.k8s.io/certificate-name": "cert-manager.io/certificate-name",
 	}
 
-	depreciations = []string{
+	deprecations = []string{
 		"certmanager.k8s.io/acme-challenge-type",
 		"certmanager.k8s.io/acme-dns01-provider",
 	}
@@ -81,7 +83,7 @@ var cmd = &cobra.Command{
 			return err
 		}
 
-		ingList, err := client.NetworkingV1beta1().Ingresses("").List(metav1.ListOptions{})
+		ingList, err := client.ExtensionsV1beta1().Ingresses("").List(metav1.ListOptions{})
 		if err != nil {
 			return err
 		}
@@ -105,13 +107,13 @@ var cmd = &cobra.Command{
 			ingStr = strings.ReplaceAll(ingStr, oldA, newA)
 		}
 
-		for _, d := range depreciations {
+		for _, d := range deprecations {
 			count := strings.Count(ingStr, d)
 			if count == 0 {
 				continue
 			}
 
-			fmt.Printf("found %d instances of %q\tthis field is DEPRECIATED and will be deleted\n", count, d)
+			fmt.Printf("found %d instances of %q\tthis field is DEPRECATED and will be deleted\n", count, d)
 
 			lines := strings.Split(ingStr, "\n")
 
@@ -134,10 +136,29 @@ var cmd = &cobra.Command{
 			return err
 		}
 
-		fmt.Printf("written new ingresses to file %q\n", newFile)
-		fmt.Printf("\nPlease check for any missing or wrong annotations in your newly generated ingress manifests.\n")
-		fmt.Printf("You are encouraged to check the diff of the two files to determine what has changed (diff %s %s).\n",
-			origFile, newFile)
+		fmt.Printf("wrote new ingresses to file %q\n", newFile)
+
+		var buff bytes.Buffer
+		diffFile := fmt.Sprintf("%s.%s.diff", origFile, newFile)
+		eCmd := exec.Command("diff", origFile, newFile)
+		eCmd.Stdout = &buff
+
+		if err := eCmd.Run(); err != nil {
+			if exitErr, ok := err.(*exec.ExitError); !ok || exitErr.ExitCode() != 1 {
+				return err
+			}
+		}
+
+		if err := ioutil.WriteFile(diffFile, buff.Bytes(), 0644); err != nil {
+			return err
+		}
+
+		fmt.Printf("wrote diff to file %q\n", diffFile)
+
+		fmt.Printf("\nPlease check for any missing or incorrect annotations in your newly generated ingress manifests.\n")
+		fmt.Printf("You should now check the diff of the two files to determine what has changed - either by inspecting the diff file %q, or running the command yourself:\n\n",
+			diffFile)
+		fmt.Printf("$ diff %s %s\n", origFile, newFile)
 
 		return nil
 	},
@@ -150,17 +171,14 @@ func writeIngressToFile(ingList *networkingv1beta.IngressList, path string) (str
 	var buff bytes.Buffer
 
 	for _, ing := range ingList.Items {
-		_, err := buff.WriteString("apiVersion: networking.k8s.io/v1beta1\nkind: Ingress\n")
-		if err != nil {
-			return "", err
-		}
+		ing.Kind = "Ingress"
+		ing.APIVersion = "extensions/v1beta1"
 
 		if err := s.Encode(&ing, &buff); err != nil {
 			return "", err
 		}
 
-		_, err = buff.WriteString("---\n")
-		if err != nil {
+		if _, err := buff.WriteString("---\n"); err != nil {
 			return "", err
 		}
 	}
@@ -173,7 +191,6 @@ func writeIngressToFile(ingList *networkingv1beta.IngressList, path string) (str
 }
 
 func main() {
-
 	cmd.PersistentFlags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "Path location to Kubeconfig")
 	cmd.PersistentFlags().StringVarP(&origFile, "original-file", "o", "ingress.yaml", "File path to store the current list of Ingress resources")
 	cmd.PersistentFlags().StringVarP(&newFile, "new-file", "n", "ingress-migrated.yaml", "File path to store the migrated Ingress resources")