Merge pull request #398 from liztio/gen-plugin

Re-add `sonobuoy gen plugin`.

cmd/sonobuoy/app/gen_plugin.go

@@ -0,0 +1,120 @@
+/*
+Copyright 2018 Heptio Inc.
+
+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 app
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"math/big"
+	"os"
+
+	"github.com/heptio/sonobuoy/pkg/config"
+	"github.com/heptio/sonobuoy/pkg/errlog"
+	"github.com/heptio/sonobuoy/pkg/plugin"
+	"github.com/heptio/sonobuoy/pkg/plugin/loader"
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+)
+
+const (
+	placeholderHostname = "<hostname>"
+)
+
+// GenPluginConfig are the input options for running
+type GenPluginConfig struct {
+	Paths      []string
+	PluginName string
+}
+
+var genPluginOpts GenPluginConfig
+
+func init() {
+	cmd := &cobra.Command{
+		Use:    "plugin",
+		Short:  "Generates the manifest Sonobuoy uses to run a worker for the given plugin",
+		Run:    genPluginManifest,
+		Hidden: true,
+		Args:   cobra.ExactArgs(1),
+	}
+
+	GenCommand.PersistentFlags().StringArrayVarP(
+		&genPluginOpts.Paths, "paths", "p", []string{".", "./examples/plugins.d/"},
+		"the paths to search for the plugins in. Defaults to . and ./plugins.d/",
+	)
+	// TODO: Other options?
+	GenCommand.AddCommand(cmd)
+}
+
+func genPluginManifest(cmd *cobra.Command, args []string) {
+	genPluginOpts.PluginName = args[0]
+	code := 0
+	manifest, err := generatePluginManifest(genPluginOpts)
+	if err == nil {
+		fmt.Printf("%s\n", manifest)
+	} else {
+		errlog.LogError(errors.Wrap(err, "error attempting to generate sonobuoy manifest"))
+		code = 1
+	}
+	os.Exit(code)
+}
+
+func generatePluginManifest(cfg GenPluginConfig) ([]byte, error) {
+	plugins, err := loader.LoadAllPlugins(
+		config.DefaultNamespace,
+		config.DefaultImage,
+		"Always",
+		cfg.Paths,
+		[]plugin.Selection{{Name: cfg.PluginName}},
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(plugins) != 1 {
+		return nil, fmt.Errorf("expected 1 plugin, got %v", len(plugins))
+	}
+
+	cert, err := genCert()
+	if err != nil {
+		return nil, err
+	}
+
+	return plugins[0].FillTemplate(placeholderHostname, cert)
+}
+
+func genCert() (*tls.Certificate, error) {
+	privKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		return nil, errors.Wrap(err, "couldn't generate private key")
+	}
+	tmpl := &x509.Certificate{
+		SerialNumber: big.NewInt(0),
+	}
+	certDER, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, &privKey.PublicKey, privKey)
+	if err != nil {
+		return nil, errors.Wrap(err, "couldn't create certificate")
+	}
+
+	return &tls.Certificate{
+		Certificate: [][]byte{certDER},
+		PrivateKey:  privKey,
+	}, nil
+}