Adds /cmd/ctl/pkg/factory which registers Kube CLI flags, and provides

clients/config needed

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

cmd/ctl/pkg/factory/BUILD.bazel

@@ -0,0 +1,31 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["factory.go"],
+    importpath = "github.com/jetstack/cert-manager/cmd/ctl/pkg/factory",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//pkg/client/clientset/versioned:go_default_library",
+        "@com_github_spf13_cobra//:go_default_library",
+        "@io_k8s_cli_runtime//pkg/genericclioptions:go_default_library",
+        "@io_k8s_client_go//kubernetes:go_default_library",
+        "@io_k8s_client_go//plugin/pkg/client/auth:go_default_library",
+        "@io_k8s_client_go//rest:go_default_library",
+        "@io_k8s_kubectl//pkg/cmd/util:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

cmd/ctl/pkg/factory/factory.go

@@ -0,0 +1,110 @@
+/*
+Copyright 2021 The cert-manager Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package factory
+
+import (
+	"github.com/spf13/cobra"
+	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/rest"
+	"k8s.io/kubectl/pkg/cmd/util"
+
+	// Load all auth plugins
+	_ "k8s.io/client-go/plugin/pkg/client/auth"
+
+	cmclient "github.com/jetstack/cert-manager/pkg/client/clientset/versioned"
+)
+
+var (
+	kubeConfigFlags = genericclioptions.NewConfigFlags(true)
+	factory         = util.NewFactory(kubeConfigFlags)
+)
+
+// Factory provides a set of clients and configurations to authenticate and
+// access a target Kubernetes cluster. Factory will ensure that its fields are
+// populated and valid during command execution.
+type Factory struct {
+	// Namespace is the namespace that the user has requested with the
+	// "--namespace" / "-n" flag. Defaults to "default" if the flag was not
+	// provided.
+	Namespace string
+
+	// EnforceNamespace will be true if the user provided the namespace flag.
+	EnforceNamespace bool
+
+	// RESTConfig is a Kubernetes REST config that contains the user's
+	// authentication and access configuration.
+	RESTConfig *rest.Config
+
+	// CMClient is a Kubernetes clientset for interacting with cert-manager APIs.
+	CMClient cmclient.Interface
+
+	// KubeClient is a Kubernetes clientset for interacting with the base
+	// Kubernetes APIs.
+	KubeClient kubernetes.Interface
+}
+
+// New returns a new Factory. The supplied command will have flags registered
+// for interacting with the Kubernetes access options. Factory will be
+// populated when the command is executed using the cobra PreRun. If a PreRun
+// is already defined, it will be executed _after_ Factory has been populated,
+// making it available.
+func New(cmd *cobra.Command) *Factory {
+	f := new(Factory)
+
+	kubeConfigFlags.AddFlags(cmd.Flags())
+
+	// Setup a PreRun to populate the Factory. Catch the existing PreRun command
+	// if one was defined, and execute it second.
+	existingPreRun := cmd.PreRun
+	cmd.PreRun = func(cmd *cobra.Command, args []string) {
+		util.CheckErr(f.complete())
+		if existingPreRun != nil {
+			existingPreRun(cmd, args)
+		}
+	}
+
+	return f
+}
+
+// complete will populate the Factory with values using the shared Kubernetes
+// CLI factory.
+func (f *Factory) complete() error {
+	var err error
+
+	f.Namespace, f.EnforceNamespace, err = factory.ToRawKubeConfigLoader().Namespace()
+	if err != nil {
+		return err
+	}
+
+	f.RESTConfig, err = factory.ToRESTConfig()
+	if err != nil {
+		return err
+	}
+
+	f.KubeClient, err = kubernetes.NewForConfig(f.RESTConfig)
+	if err != nil {
+		return err
+	}
+
+	f.CMClient, err = cmclient.NewForConfig(f.RESTConfig)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}