Add moby run packet to boot on baremetal Packet.net hosts

This uses the Packet.net API and iPXE to boot a Moby host.
There are several enhancements coming soon, such as SSH key
customisation, but this PR is sufficient to boot a host and
then use the web interface to get console access.

The user must currently upload the built artefacts to a public
URL and specify it via --base-url, e.g.:
moby run packet --api-key <key> --project-id <id> \
  --base-url http://recoil.org/~avsm/ipxe --hostname test-moby packet

See #1424 #1245 for related issues.

Signed-off-by: Anil Madhavapeddy <anil@docker.com>

src/cmd/moby/run.go

@@ -18,6 +18,7 @@ func runUsage() {
 	fmt.Printf("  hyperkit [macOS]\n")
 	fmt.Printf("  qemu [linux]\n")
 	fmt.Printf("  vmware\n")
+	fmt.Printf("  packet\n")
 	fmt.Printf("\n")
 	fmt.Printf("'options' are the backend specific options.\n")
 	fmt.Printf("See 'moby run [backend] --help' for details.\n\n")
@@ -43,6 +44,8 @@ func run(args []string) {
 		runGcp(args[1:])
 	case "qemu":
 		runQemu(args[1:])
+	case "packet":
+		runPacket(args[1:])
 	default:
 		switch runtime.GOOS {
 		case "darwin":

src/cmd/moby/run_packet.go

@@ -0,0 +1,113 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	log "github.com/Sirupsen/logrus"
+	"github.com/packethost/packngo"
+	"net/http"
+	"os"
+)
+
+const (
+	packetDefaultZone     = "ams1"
+	packetDefaultMachine  = "baremetal_0"
+	packetDefaultHostname = "moby"
+	packetBaseURL         = "PACKET_BASE_URL"
+	packetZoneVar         = "PACKET_ZONE"
+	packetMachineVar      = "PACKET_MACHINE"
+	packetAPIKeyVar       = "PACKET_API_KEY"
+	packetProjectIDVar    = "PACKET_PROJECT_ID"
+	packetHostnameVar     = "PACKET_HOSTNAME"
+	packetNameVar         = "PACKET_NAME"
+)
+
+// ValidateHTTPURL does a sanity check that a URL returns a 200 or 300 response
+func ValidateHTTPURL(url string) {
+	log.Printf("Validating URL: %s", url)
+	resp, err := http.Head(url)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if resp.StatusCode >= 400 {
+		log.Fatal("Got a non 200- or 300- HTTP response code: %s", resp)
+	}
+	log.Printf("OK: %d response code", resp.StatusCode)
+}
+
+// Process the run arguments and execute run
+func runPacket(args []string) {
+	packetCmd := flag.NewFlagSet("packet", flag.ExitOnError)
+	packetCmd.Usage = func() {
+		fmt.Printf("USAGE: %s run packet [options] [name]\n\n", os.Args[0])
+		fmt.Printf("Options:\n\n")
+		packetCmd.PrintDefaults()
+	}
+	baseURLFlag := packetCmd.String("base-url", "", "Base URL that the kernel and initrd are served from.")
+	zoneFlag := packetCmd.String("zone", packetDefaultZone, "Packet Zone")
+	machineFlag := packetCmd.String("machine", packetDefaultMachine, "Packet Machine Type")
+	apiKeyFlag := packetCmd.String("api-key", "", "Packet API key")
+	projectFlag := packetCmd.String("project-id", "", "Packet Project ID")
+	hostNameFlag := packetCmd.String("hostname", packetDefaultHostname, "Hostname of new instance")
+	nameFlag := packetCmd.String("img-name", "", "Overrides the prefix used to identify the files. Defaults to [name]")
+	if err := packetCmd.Parse(args); err != nil {
+		log.Fatal("Unable to parse args")
+	}
+
+	remArgs := packetCmd.Args()
+	prefix := "packet"
+	if len(remArgs) > 0 {
+		prefix = remArgs[0]
+	}
+
+	url := getStringValue(packetBaseURL, *baseURLFlag, "")
+	if url == "" {
+		log.Fatal("Need to specify a value for --base-url where the images are hosted. This URL should contain <url>/%s-bzImage and <url>/%s-initrd.img")
+	}
+	facility := getStringValue(packetZoneVar, *zoneFlag, "")
+	plan := getStringValue(packetMachineVar, *machineFlag, defaultMachine)
+	apiKey := getStringValue(packetAPIKeyVar, *apiKeyFlag, "")
+	if apiKey == "" {
+		log.Fatal("Must specify a Packet.net API key with --api-key")
+	}
+	projectID := getStringValue(packetProjectIDVar, *projectFlag, "")
+	if projectID == "" {
+		log.Fatal("Must specify a Packet.net Project ID with --project-id")
+	}
+	hostname := getStringValue(packetHostnameVar, *hostNameFlag, "")
+	name := getStringValue(packetNameVar, *nameFlag, prefix)
+	osType := "custom_ipxe"
+	billing := "hourly"
+	userData := fmt.Sprintf("#!ipxe\n\ndhcp\nset base-url %s\nset kernel-params ip=dhcp nomodeset ro serial console=ttyS1,115200\nkernel ${base-url}/%s-bzImage ${kernel-params}\ninitrd ${base-url}/%s-initrd.img\nboot", url, name, name)
+	log.Debugf("Using userData of:\n%s\n", userData)
+	initrdURL := fmt.Sprintf("%s/%s-initrd.img", url, name)
+	kernelURL := fmt.Sprintf("%s/%s-bzImage", url, name)
+	ValidateHTTPURL(kernelURL)
+	ValidateHTTPURL(initrdURL)
+	client := packngo.NewClient("", apiKey, nil)
+	tags := []string{}
+	req := packngo.DeviceCreateRequest{
+		HostName:     hostname,
+		Plan:         plan,
+		Facility:     facility,
+		OS:           osType,
+		BillingCycle: billing,
+		ProjectID:    projectID,
+		UserData:     userData,
+		Tags:         tags,
+	}
+	d, _, err := client.Devices.Create(&req)
+	if err != nil {
+		log.Fatal(err)
+	}
+	b, err := json.MarshalIndent(d, "", "    ")
+	if err != nil {
+		log.Fatal(err)
+	}
+	// log response json if in verbose mode
+	log.Debugf("%s\n", string(b))
+	// TODO: poll events api for bringup (requires extpacknogo)
+	// TODO: connect to serial console (requires API extension to get SSH URI)
+	// TODO: add ssh keys via API registered keys
+}