Add workload daemon

Dockerfile.workload-daemon

@@ -0,0 +1,19 @@
+# Copyright 2020 The Kubernetes Authors. All rights reserved.
+#
+# 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.
+
+# This image requires ca-certificate, which is pre-installed in distroless.
+FROM gcr.io/distroless/static:latest
+
+ADD bin/ARG_ARCH/ARG_BIN /ARG_BIN
+ENTRYPOINT ["/ARG_BIN"]

Makefile

@@ -29,7 +29,8 @@ CONTAINER_BINARIES ?= \
 	echo \
 	fuzzer \
 	glbc \
-	workload-controller
+	workload-controller \
+	workload-daemon
 
 # Latest commit hash for current branch.
 GIT_COMMIT := $(shell git rev-parse HEAD)

cmd/workload-daemon/main.go

@@ -0,0 +1,76 @@
+/*
+Copyright 2020 The Kubernetes 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 main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"time"
+
+	daemon "k8s.io/ingress-gce/pkg/experimental/workload/daemon"
+	gce "k8s.io/ingress-gce/pkg/experimental/workload/daemon/provider/gce"
+	"k8s.io/klog"
+
+	// GCP Authentication
+	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
+)
+
+func main() {
+	cmdSet := flag.NewFlagSet("cmd", flag.ExitOnError)
+	provider := cmdSet.String("provider", "gce", "The provider of this external workload.")
+	updateInterval := cmdSet.Duration("interval", 30*time.Second, "The resync interval.")
+
+	if len(os.Args) < 2 {
+		outputHelp()
+		return
+	}
+	cmdSet.Parse(os.Args[2:])
+	if *provider != "gce" {
+		klog.Fatalf("Current implementation only supports gce provider.")
+	}
+
+	switch os.Args[1] {
+	case "get-credentials":
+		vm, err := gce.NewVM()
+		if err != nil {
+			klog.Fatalf("unable to initialize GCE VM: %+v", err)
+		}
+		credentials, err := vm.Credentials()
+		if err != nil {
+			klog.Fatalf("unable to get credentials: %+v", err)
+		}
+		daemon.OutputCredentials(credentials)
+		return
+	case "start":
+		klog.V(0).Infof("Workload daemon started")
+		vm, err := gce.NewVM()
+		if err != nil {
+			klog.Fatalf("unable to initialize GCE VM: %+v", err)
+		}
+		daemon.RunDaemon(vm, vm, *updateInterval)
+		return
+	default:
+		outputHelp()
+		return
+	}
+}
+
+func outputHelp() {
+	fmt.Printf("Usage: %v [command]\n", os.Args[0])
+	fmt.Printf("command:\n    start\n    get-credentials\n")
+}