Initial checkin for oci generate

Signed-off-by: Mrunal Patel <mrunalp@gmail.com>

generate.go

@@ -0,0 +1,252 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"runtime"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/codegangsta/cli"
+	"github.com/opencontainers/specs"
+)
+
+var generateCommand = cli.Command{
+	Name:  "generate",
+	Usage: "generate a OCI spec file",
+	Action: func(context *cli.Context) {
+		spec := specs.LinuxSpec{
+			Spec: specs.Spec{
+				Version: specs.Version,
+				Platform: specs.Platform{
+					OS:   runtime.GOOS,
+					Arch: runtime.GOARCH,
+				},
+				Root: specs.Root{
+					Path:     "rootfs",
+					Readonly: true,
+				},
+				Process: specs.Process{
+					Terminal: true,
+					User:     specs.User{},
+					Args: []string{
+						"sh",
+					},
+					Env: []string{
+						"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
+						"TERM=xterm",
+					},
+				},
+				Hostname: "shell",
+				Mounts: []specs.MountPoint{
+					{
+						Name: "proc",
+						Path: "/proc",
+					},
+					{
+						Name: "dev",
+						Path: "/dev",
+					},
+					{
+						Name: "devpts",
+						Path: "/dev/pts",
+					},
+					{
+						Name: "shm",
+						Path: "/dev/shm",
+					},
+					{
+						Name: "mqueue",
+						Path: "/dev/mqueue",
+					},
+					{
+						Name: "sysfs",
+						Path: "/sys",
+					},
+					{
+						Name: "cgroup",
+						Path: "/sys/fs/cgroup",
+					},
+				},
+			},
+			Linux: specs.Linux{
+				Capabilities: []string{
+					"AUDIT_WRITE",
+					"KILL",
+					"NET_BIND_SERVICE",
+				},
+			},
+		}
+		rspec := specs.LinuxRuntimeSpec{
+			RuntimeSpec: specs.RuntimeSpec{
+				Mounts: map[string]specs.Mount{
+					"proc": {
+						Type:    "proc",
+						Source:  "proc",
+						Options: nil,
+					},
+					"dev": {
+						Type:    "tmpfs",
+						Source:  "tmpfs",
+						Options: []string{"nosuid", "strictatime", "mode=755", "size=65536k"},
+					},
+					"devpts": {
+						Type:    "devpts",
+						Source:  "devpts",
+						Options: []string{"nosuid", "noexec", "newinstance", "ptmxmode=0666", "mode=0620", "gid=5"},
+					},
+					"shm": {
+						Type:    "tmpfs",
+						Source:  "shm",
+						Options: []string{"nosuid", "noexec", "nodev", "mode=1777", "size=65536k"},
+					},
+					"mqueue": {
+						Type:    "mqueue",
+						Source:  "mqueue",
+						Options: []string{"nosuid", "noexec", "nodev"},
+					},
+					"sysfs": {
+						Type:    "sysfs",
+						Source:  "sysfs",
+						Options: []string{"nosuid", "noexec", "nodev"},
+					},
+					"cgroup": {
+						Type:    "cgroup",
+						Source:  "cgroup",
+						Options: []string{"nosuid", "noexec", "nodev", "relatime", "ro"},
+					},
+				},
+			},
+			Linux: specs.LinuxRuntime{
+				Namespaces: []specs.Namespace{
+					{
+						Type: "pid",
+					},
+					{
+						Type: "network",
+					},
+					{
+						Type: "ipc",
+					},
+					{
+						Type: "uts",
+					},
+					{
+						Type: "mount",
+					},
+				},
+				Rlimits: []specs.Rlimit{
+					{
+						Type: "RLIMIT_NOFILE",
+						Hard: uint64(1024),
+						Soft: uint64(1024),
+					},
+				},
+				Devices: []specs.Device{
+					{
+						Type:        'c',
+						Path:        "/dev/null",
+						Major:       1,
+						Minor:       3,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+					{
+						Type:        'c',
+						Path:        "/dev/random",
+						Major:       1,
+						Minor:       8,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+					{
+						Type:        'c',
+						Path:        "/dev/full",
+						Major:       1,
+						Minor:       7,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+					{
+						Type:        'c',
+						Path:        "/dev/tty",
+						Major:       5,
+						Minor:       0,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+					{
+						Type:        'c',
+						Path:        "/dev/zero",
+						Major:       1,
+						Minor:       5,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+					{
+						Type:        'c',
+						Path:        "/dev/urandom",
+						Major:       1,
+						Minor:       9,
+						Permissions: "rwm",
+						FileMode:    0666,
+						UID:         0,
+						GID:         0,
+					},
+				},
+				Resources: &specs.Resources{
+					Memory: specs.Memory{
+						Swappiness: -1,
+					},
+				},
+				Seccomp: specs.Seccomp{
+					DefaultAction: "SCMP_ACT_ALLOW",
+					Syscalls:      []*specs.Syscall{},
+				},
+			},
+		}
+		checkNoFile := func(name string) error {
+			_, err := os.Stat(name)
+			if err == nil {
+				return fmt.Errorf("File %s exists. Remove it first", name)
+			}
+			if !os.IsNotExist(err) {
+				return err
+			}
+			return nil
+		}
+		cName := "config.json"
+		rName := "runtime.json"
+		if err := checkNoFile(cName); err != nil {
+			logrus.Fatal(err)
+		}
+		if err := checkNoFile(rName); err != nil {
+			logrus.Fatal(err)
+		}
+		data, err := json.MarshalIndent(&spec, "", "\t")
+		if err != nil {
+			logrus.Fatal(err)
+		}
+		if err := ioutil.WriteFile(cName, data, 0666); err != nil {
+			logrus.Fatal(err)
+		}
+		rdata, err := json.MarshalIndent(&rspec, "", "\t")
+		if err != nil {
+			logrus.Fatal(err)
+		}
+		if err := ioutil.WriteFile(rName, rdata, 0666); err != nil {
+			logrus.Fatal(err)
+		}
+	},
+}

main.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"os"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/codegangsta/cli"
+)
+
+func main() {
+	app := cli.NewApp()
+	app.Name = "oci"
+	app.Version = "0.0.1"
+
+	app.Commands = []cli.Command{
+		generateCommand,
+	}
+
+	if err := app.Run(os.Args); err != nil {
+		logrus.Fatal(err)
+	}
+}