Initial commit

cmd/main.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"context"
+	"crypto/tls"
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/golang/glog"
+)
+
+func main() {
+	parameters := DefaultParametersObject()
+
+	// get command line parameters
+	flag.IntVar(&parameters.port, "port", LookupIntEnv("CONFIG_PORT", parameters.port), "Webhook server port.")
+	flag.StringVar(&parameters.certFile, "tlsCertFile", LookupStringEnv("CONFIG_CERT_PATH", parameters.certFile), "File containing the x509 Certificate for HTTPS.")
+	flag.StringVar(&parameters.keyFile, "tlsKeyFile", LookupStringEnv("CONFIG_KEY_PATH", parameters.keyFile), "File containing the x509 private key to --tlsCertFile.")
+	flag.StringVar(&parameters.excludeNamespaces, "excludeNamespaces", LookupStringEnv("CONFIG_EXCLUDE_NAMESPACES", parameters.excludeNamespaces), "Comma-separated namespace names to ignore.")
+
+	flag.StringVar(&parameters.targetSecretAnnotation, "targetSecretAnnotation", LookupStringEnv("CONFIG_TARGET_SECRET_ANNOTATION", parameters.targetSecretAnnotation), "Annotation of the targetSecret secret we will create in the namespace")
+	flag.StringVar(&parameters.targetSecretName, "targetSecretName", LookupStringEnv("CONFIG_TARGET_SECRET_NAME", parameters.targetSecretName), "Name of the targetSecret secret we will create in the namespace")
+
+	flag.Parse()
+
+	glog.Infof("Running with config: %+v", parameters)
+
+	whsvr, err := NewWebhookServer(
+		&parameters,
+		&http.Server{
+			Addr: fmt.Sprintf(":%v", parameters.port),
+			// This is quite inefficient as it loads file contents on every TLS ClientHello, but ¯\_(ツ)_/¯
+			TLSConfig: &tls.Config{GetCertificate: func(info *tls.ClientHelloInfo) (*tls.Certificate, error) {
+				glog.Infof("Loading certificates")
+				cert, err := tls.LoadX509KeyPair(parameters.certFile, parameters.keyFile)
+				return &cert, err
+			}},
+		},
+	)
+	if err != nil {
+		glog.Exitf("Could not create the Webhook server: %v", err)
+	}
+
+	// define http server and server handler
+	mux := http.NewServeMux()
+	mux.HandleFunc("/mutate", whsvr.serve)
+	whsvr.server.Handler = mux
+
+	// start webhook server in new rountine
+	go func() {
+		if err := whsvr.server.ListenAndServeTLS(parameters.certFile, parameters.keyFile); err != nil {
+			glog.Errorf("Failed to listen and serve webhook server: %v", err)
+		}
+	}()
+
+	// listening OS shutdown singal
+	signalChan := make(chan os.Signal, 1)
+	signal.Notify(signalChan, syscall.SIGINT, syscall.SIGTERM)
+	<-signalChan
+
+	glog.Infof("Got OS shutdown signal, shutting down webhook server gracefully...")
+	if err := whsvr.server.Shutdown(context.Background()); err != nil {
+		glog.Errorf("Error while shutting down: %v", err)
+	}
+}