add cl-k8s

Signed-off-by: Jess Frazelle <acidburn@microsoft.com>

add attributes

Signed-off-by: Jess Frazelle <acidburn@microsoft.com>

.gitattributes

@@ -0,0 +1 @@
+examples/*/bindata.go filter=lfs diff=lfs merge=lfs -text

Makefile

@@ -9,19 +9,30 @@ GO_LDFLAGS_STATIC=-ldflags "-w -extldflags -static"
 all: clean build fmt lint test staticcheck vet ## Runs a clean, build, fmt, lint, test, staticcheck, and vet
 
 .PHONY: build
-build: alpine busybox ## Builds a static executable or package
+build: alpine busybox cl-k8s ## Builds a static executable or package
 
 .PHONY: alpine
-alpine: generate
+alpine:
 	@echo "+ $@"
+	go generate ./examples/$@/...
 	CGO_ENABLED=1 go build \
 				-tags "$(BUILDTAGS) static_build" \
 				${GO_LDFLAGS_STATIC} -o $@ ./examples/$@/...
 	@echo "Static container for $@ created at: ./$@"
 
 .PHONY: busybox
-busybox: generate
+busybox:
 	@echo "+ $@"
+	go generate ./examples/$@/...
+	CGO_ENABLED=1 go build \
+				-tags "$(BUILDTAGS) static_build" \
+				${GO_LDFLAGS_STATIC} -o $@ ./examples/$@/...
+	@echo "Static container for $@ created at: ./$@"
+
+.PHONY: cl-k8s
+cl-k8s:
+	@echo "+ $@"
+	go generate ./examples/$@/...
 	CGO_ENABLED=1 go build \
 				-tags "$(BUILDTAGS) static_build" \
 				${GO_LDFLAGS_STATIC} -o $@ ./examples/$@/...
@@ -81,14 +92,10 @@ tag: ## Create a new git tag to prepare to build a release
 	git tag -sa $(VERSION) -m "$(VERSION)"
 	@echo "Run git push origin $(VERSION) to push your new tag to GitHub and trigger a travis build."
 
-.PHONY: generate
-generate:
-	GOMAXPROCS=1 go generate ./...
-
 .PHONY: clean
 clean: ## Cleanup any build binaries or packages
 	@echo "+ $@"
-	$(RM) alpine busybox
+	$(RM) alpine busybox cl-k8s
 	@sudo $(RM) -r rootfs
 
 .PHONY: help

README.md

@@ -30,8 +30,12 @@ $ make alpine
 Static container created at: ./alpine
 
 # building the busybox example
-$ make alpine
+$ make busybox
 Static container created at: ./busybox
+
+# building the cl-k8s example
+$ make cl-k8s
+Static container created at: ./cl-k8s
 ```
 
 ### Running
@@ -39,6 +43,7 @@ Static container created at: ./busybox
 ```console
 $ ./alpine
 $ ./busybox
+$ ./cl-k8s
 ```
 
 ## Cool things

container/spec.go

@@ -18,6 +18,7 @@ type SpecOpts struct {
 	Readonly bool
 	Terminal bool
 	Args     []string
+	Mounts   []specs.Mount
 	Hooks    *specs.Hooks
 }
 
@@ -55,5 +56,9 @@ func Spec(opts SpecOpts) *specs.Spec {
 		spec.Process.Args = opts.Args
 	}
 
+	if opts.Mounts != nil {
+		spec.Mounts = append(spec.Mounts, opts.Mounts...)
+	}
+
 	return spec
 }

examples/cl-k8s/generate.go

@@ -0,0 +1,18 @@
+// +build ignore
+
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/genuinetools/binctr/container"
+)
+
+// Pulls an image and saves the binary data in the container package bindata.go.
+func main() {
+	if err := container.EmbedImage("r.j3ss.co/clisp"); err != nil {
+		fmt.Fprintf(os.Stderr, "embed image failed: %v\n", err)
+		os.Exit(1)
+	}
+}

examples/cl-k8s/main.go

@@ -0,0 +1,157 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/genuinetools/binctr/container"
+	"github.com/opencontainers/runc/libcontainer"
+	_ "github.com/opencontainers/runc/libcontainer/nsenter"
+	specs "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	defaultRoot      = "/tmp/binctr-cl-k8s"
+	defaultRootfsDir = "rootfs"
+)
+
+var (
+	containerID string
+	root        string
+
+	file string
+)
+
+func init() {
+	// Parse flags
+	flag.StringVar(&containerID, "id", "cl-k8s", "container ID")
+	flag.StringVar(&root, "root", defaultRoot, "root directory of container state, should be tmpfs")
+
+	flag.Usage = func() {
+		flag.PrintDefaults()
+	}
+
+	flag.Parse()
+
+	if flag.NArg() < 1 {
+		logrus.Fatal("pass a file to run with cl-k8s")
+	}
+
+	// Get the file args passed.
+	file := flag.Arg(0)
+	// Get the absolute path.
+	var err error
+	file, err = filepath.Abs(file)
+	if err != nil {
+		logrus.Fatal(err)
+	}
+	// Check if its  directory.
+	fi, err := os.Stat(file)
+	if err != nil {
+		logrus.Fatal(err)
+	}
+	if !fi.Mode().IsDir() {
+		// Copy the file to a temporary directory.
+		file, err = copyFile(file)
+		if err != nil {
+			logrus.Fatal(err)
+		}
+		fmt.Printf("new file is %s\n", file)
+	}
+}
+
+//go:generate go run generate.go
+func main() {
+	if len(os.Args) > 1 && os.Args[1] == "init" {
+		runInit()
+		return
+	}
+
+	// Create a new container spec with the following options.
+	opts := container.SpecOpts{
+		Rootless: true,
+		Terminal: true,
+		Args:     []string{"clisp", filepath.Join("/home/user/scripts", filepath.Base(file))},
+		Mounts: []specs.Mount{
+			{
+				Destination: "/home/user/scripts/",
+				Type:        "bind",
+				Source:      filepath.Dir(file),
+				Options:     []string{"bind", "ro"},
+			},
+		},
+	}
+	fmt.Printf("opts %#v\n", opts)
+	spec := container.Spec(opts)
+
+	// Initialize the container object.
+	c := &container.Container{
+		ID:       containerID,
+		Spec:     spec,
+		Root:     root,
+		Rootless: true,
+	}
+
+	// Unpack the rootfs.
+	if err := c.UnpackRootfs(defaultRootfsDir, Asset); err != nil {
+		logrus.Fatal(err)
+	}
+
+	// Run the container.
+	status, err := c.Run()
+	if err != nil {
+		logrus.Fatal(err)
+	}
+
+	// Remove the rootfs after the container has exited.
+	if err := os.RemoveAll(defaultRootfsDir); err != nil {
+		logrus.Warnf("removing rootfs failed: %v", err)
+	}
+
+	// Exit with the container's exit status.
+	os.Exit(status)
+}
+
+func runInit() {
+	runtime.GOMAXPROCS(1)
+	runtime.LockOSThread()
+	factory, _ := libcontainer.New("")
+	if err := factory.StartInitialization(); err != nil {
+		// as the error is sent back to the parent there is no need to log
+		// or write it to stderr because the parent process will handle this
+		os.Exit(1)
+	}
+	panic("libcontainer: container init failed to exec")
+}
+
+// copyFile copies the src file to a temporary directory.
+func copyFile(src string) (string, error) {
+	in, err := os.Open(src)
+	if err != nil {
+		return "", err
+	}
+	defer in.Close()
+
+	tmpd, err := ioutil.TempDir("", "")
+	if err != nil {
+		return "", err
+	}
+
+	out, err := os.Create(filepath.Join(tmpd, filepath.Base(src)))
+	if err != nil {
+		return "", err
+	}
+	defer out.Close()
+
+	_, err = io.Copy(out, in)
+	if err != nil {
+		return "", err
+	}
+	return out.Name(), out.Close()
+}