cmd/botanist/main.go - infra/infra - Git at Google

 // Copyright 2017 The Fuchsia Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 package main

 import (
 	"archive/tar"
 	"bytes"
 	"context"
 	"encoding/json"
 	"flag"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"log"
 	"net"
 	"os"
 	"os/signal"
 	"path"
 	"path/filepath"
 	"strings"
 	"syscall"
 	"time"

 	"fuchsia.googlesource.com/infra/infra/netboot"
 	"fuchsia.googlesource.com/infra/infra/pdu"
 	"fuchsia.googlesource.com/infra/infra/retry"
 	"fuchsia.googlesource.com/infra/infra/tftp"
 )

 const (
 	netbootFilenamePrefix = "<<netboot>>"
 	kernelFilename        = netbootFilenamePrefix + "kernel.bin"
 	ramdiskFilename       = netbootFilenamePrefix + "ramdisk.bin"
 	cmdlineFilename       = netbootFilenamePrefix + "cmdline"

 	imageFilenamePrefix = "<<image>>"
 	efiFilename         = imageFilenamePrefix + "efi.img"
 	kerncFilename       = imageFilenamePrefix + "kernc.img"
 	fvmFilename         = imageFilenamePrefix + "sparse.fvm"

 	summaryFilename = "summary.json"
 )

 type stringsFlag []string

 func (s *stringsFlag) Set(val string) error {
 	*s = append(*s, val)
 	return nil
 }

 func (s *stringsFlag) String() string {
 	if s == nil {
 		return ""
 	}
 	return strings.Join([]string(*s), ", ")
 }

 var (
 	config           string        // config file path
 	kernelImage      string        // path to kernel image
 	ramdiskImage     string        // path to ramdisk image
 	efiImage         string        // path to efi image
 	kerncImage       string        // path to kernc image
 	fvmImages        stringsFlag   // list of paths to fvm images
 	testdir          string        // path to test directory
 	cmdline          string        // path to a file containing kernel cmdline args.
 	outfile          string        // path to output file
 	fileName         string        // name of the file in the test directory
 	filePollInterval time.Duration // poll interval for file on device
 )

 func init() {
 	flag.StringVar(&config, "config", "/etc/botanist/config.json", "config file path")
 	flag.StringVar(&kernelImage, "kernel", "", "path to kernel image")
 	flag.StringVar(&ramdiskImage, "ramdisk", "", "path to ramdisk image")
 	flag.StringVar(&efiImage, "efi", "", "path to efi image to be paved")
 	flag.StringVar(&kerncImage, "kernc", "", "path to kernc image to be paved")
 	flag.Var(&fvmImages, "fvm", "path to a sparse fvm image to be paved (may be specified up to 4 times)")
 	flag.StringVar(&cmdline, "cmdline", "", "path to a file containing command line arguments")
 	flag.StringVar(&testdir, "test", "/test", "path to test directory")
 	flag.StringVar(&outfile, "out", "output.tar", "path to output file")
 	flag.StringVar(&fileName, "file-name", summaryFilename, "name of the file in the test directory")
 	flag.DurationVar(&filePollInterval, "file-poll-interval", 1*time.Minute, "time between checking for summary.json on the target")
 }

 // Files is an ordered map for files which will be TFTP'd over to zedboot.
 type Files struct {
 	remotes []string
 	locals  [][]string
 }

 // Set adds a configuration of what files to send for to the remote name.
 func (f *Files) Set(remote string, locals ...string) {
 	f.remotes = append(f.remotes, remote)
 	f.locals = append(f.locals, locals)
 }

 // Foreach calls a callback for each file to send in a filesMap.
 func (f *Files) Foreach(c func(remote, local string) error) error {
 	for i := 0; i < len(f.remotes); i++ {
 		for j := 0; j < len(f.locals[i]); j++ {
 			if err := c(f.remotes[i], f.locals[i][j]); err != nil {
 				return err
 			}
 		}
 	}
 	return nil
 }

 // Config contains the application configuration.
 type Config struct {
 	// Nodname is the hostname of the hardware device we want to boot on.
 	Nodename string `json:"nodename"`

 	// PDU is the configuration for the PDU attached to the hardware device.
 	PDU *pdu.Config `json:"pdu,omitempty"`
 }

 // Summary is the runtest summary output file format.
 type Summary struct {
 	Tests []struct {
 		Name       string `json:"name"`
 		OutputFile string `json:"output_file"`
 		Result     string `json:"result"`
 		DataSinks  map[string][]struct {
 			Name string `json:"name"`
 			File string `json:"file"`
 		} `json:"data_sinks,omitempty"`
 	} `json:"tests"`
 	Outputs map[string]string `json:"outputs,omitempty"`
 }

 func writeFileToTar(client *tftp.Client, tftpAddr *net.UDPAddr, tw *tar.Writer, testDir string, outputFile string) error {
 	writer, err := client.Receive(tftpAddr, path.Join(testDir, outputFile))
 	if err != nil {
 		return fmt.Errorf("failed to receive file %s: %v\n", outputFile, err)
 	}
 	hdr := &tar.Header{
 		Name: outputFile,
 		Size: writer.(tftp.Session).Size(),
 		Mode: 0666,
 	}
 	if err := tw.WriteHeader(hdr); err != nil {
 		return fmt.Errorf("failed to write file header: %v\n", err)
 	}
 	if _, err := writer.WriteTo(tw); err != nil {
 		return fmt.Errorf("failed to write file content: %v\n", err)
 	}

 	return nil
 }

 func runTests(ctx context.Context, config *Config, files *Files, args []string) error {
 	// Find the node address UDP address.
 	n := netboot.NewClient(time.Second)

 	var addr *net.UDPAddr
 	var err error
 	// We need to retry here because botanist might try to discover before
 	// zedboot is fully ready, so the packet that's sent out doesn't result
 	// in any reply. We don't need to wait between calls because Discover
 	// already has a 1 minute timeout for reading a UDP packet from zedboot.
 	err = retry.Retry(ctx, retry.WithMaxRetries(retry.NewConstantBackoff(time.Second), 60), func() error {
 		addr, err = n.Discover(config.Nodename, false)
 		return err
 	})
 	if err != nil {
 		return fmt.Errorf("cannot find node \"%s\": %v\n", config.Nodename, err)
 	}

 	// Transfer kernel, ramdisk, and command line args onto the node.
 	client := tftp.NewClient()
 	tftpAddr := &net.UDPAddr{
 		IP:   addr.IP,
 		Port: tftp.ClientPort,
 		Zone: addr.Zone,
 	}

 	if err := transferFiles(ctx, client, tftpAddr, files, args); err != nil {
 		return fmt.Errorf("cannot transfer files: %v\n", err)
 	}

 	// Set up log listener and dump kernel output to stdout.
 	l, err := netboot.NewLogListener(config.Nodename)
 	if err != nil {
 		return fmt.Errorf("cannot listen: %v\n", err)
 	}
 	go func() {
 		defer l.Close()
 		log.Printf("starting log listener\n")
 		for {
 			data, err := l.Listen()
 			if err != nil {
 				continue
 			}
 			fmt.Print(data)
 			select {
 			case <-ctx.Done():
 				return
 			default:
 			}
 		}
 	}()

 	log.Printf("sending boot command\n")

 	// Boot Fuchsia.
 	if err := n.Boot(addr); err != nil {
 		return fmt.Errorf("cannot boot: %v\n", err)
 	}

 	log.Printf("waiting for \"%s\"\n", fileName)

 	// Poll for summary.json; this relies on runtest being executed using
 	// autorun and it eventually producing the summary.json file.
 	var buffer bytes.Buffer
 	var writer io.WriterTo
 	err = retry.Retry(ctx, retry.NewConstantBackoff(filePollInterval), func() error {
 		writer, err = client.Receive(tftpAddr, path.Join(testdir, fileName))
 		return err
 	})
 	if err != nil {
 		return fmt.Errorf("timed out waiting for tests to complete: %v", err)
 	}

 	log.Printf("reading \"%s\"\n", fileName)

 	if _, err := writer.WriteTo(&buffer); err != nil {
 		return fmt.Errorf("failed to receive summary file: %v\n", err)
 	}

 	// Parse and save the summary.json file.
 	var result Summary
 	if err := json.Unmarshal(buffer.Bytes(), &result); err != nil {
 		return fmt.Errorf("cannot unmarshall test results: %v\n", err)
 	}

 	file, err := os.OpenFile(outfile, os.O_WRONLY|os.O_CREATE, 0666)
 	if err != nil {
 		return fmt.Errorf("failed to create file %s: %v\n", outfile, err)
 	}
 	tw := tar.NewWriter(file)
 	defer tw.Close()

 	hdr := &tar.Header{
 		Name: summaryFilename,
 		Size: int64(buffer.Len()),
 		Mode: 0666,
 	}
 	if err := tw.WriteHeader(hdr); err != nil {
 		return fmt.Errorf("failed to write summary header: %v\n", err)
 	}
 	if _, err := tw.Write(buffer.Bytes()); err != nil {
 		return fmt.Errorf("failed to write summary content: %v\n", err)
 		log.Fatal(err)
 	}

 	log.Printf("copying test output\n")

 	// Copy test output from the node.
 	for _, path := range result.Outputs {
 		if err = writeFileToTar(client, tftpAddr, tw, testdir, path); err != nil {
 			return err
 		}
 	}
 	for _, test := range result.Tests {
 		if err = writeFileToTar(client, tftpAddr, tw, testdir, test.OutputFile); err != nil {
 			return err
 		}
 		// Copy data sinks if any are present.
 		for _, sinks := range test.DataSinks {
 			for _, sink := range sinks {
 				if err = writeFileToTar(client, tftpAddr, tw, testdir, sink.File); err != nil {
 					return err
 				}
 			}
 		}
 	}

 	return nil
 }

 // transferFiles sends kernel, optionally ramdisk, and any command line args to
 // node.
 func transferFiles(ctx context.Context, client *tftp.Client, addr *net.UDPAddr, files *Files, cmdline []string) error {
 	err := files.Foreach(func(remote, local string) error {
 		file, err := os.Open(local)
 		if err != nil {
 			return fmt.Errorf("cannot open %s: %v\n", local, err)
 		}
 		defer file.Close()

 		fi, err := file.Stat()
 		if err != nil {
 			return fmt.Errorf("cannot stat %s: %v\n", local, err)
 		}
 		// We need to retry because in the event of paving, TFTP might tell us
 		// it's not ready yet.
 		return retry.Retry(ctx, retry.WithMaxRetries(retry.NewConstantBackoff(time.Second), 60), func() error {
 			fmt.Printf("attempting to send %s=%s\n", remote, filepath.Base(local))
 			reader, err := client.Send(addr, remote, fi.Size())
 			if err != nil {
 				return fmt.Errorf("failed to send %s: %v\n", remote, err)
 			}
 			if _, err := reader.ReadFrom(file); err != nil {
 				return fmt.Errorf("failed to send %s data: %v\n", local, err)
 			}
 			return nil
 		})
 	})
 	if err != nil {
 		return err
 	}
 	if len(cmdline) > 0 {
 		var b bytes.Buffer
 		for _, arg := range cmdline {
 			fmt.Fprintf(&b, "%s\n", arg)
 		}

 		log.Printf("sending cmdline \"%s\"", b.String())

 		reader, err := client.Send(addr, cmdlineFilename, int64(b.Len()))
 		if err != nil {
 			return fmt.Errorf("failed to send cmdline: %v\n", err)
 		}
 		if _, err := reader.ReadFrom(bytes.NewReader(b.Bytes())); err != nil {
 			return fmt.Errorf("failed to read cmdline data: %v\n", err)
 		}
 	}
 	return nil
 }

 func loadConfig(ctx context.Context, path string) (*Config, error) {
 	file, err := os.Open(path)
 	if err != nil {
 		return nil, err
 	}

 	var config Config
 	if err := json.NewDecoder(file).Decode(&config); err != nil {
 		return nil, err
 	}

 	return &config, err
 }

 func run(ctx context.Context, config *Config, files *Files, cmdline []string) error {
 	if config.PDU != nil {
 		defer func() {
 			log.Printf("rebooting the node \"%s\"\n", config.Nodename)

 			if err := pdu.RebootDevice(config.PDU); err != nil {
 				log.Fatalf("failed to reboot the device: %v", err)
 			}
 		}()
 	}

 	ctx, cancel := context.WithCancel(ctx)

 	// Handle SIGTERM and make sure we send a reboot to the device.
 	signals := make(chan os.Signal, 1)
 	signal.Notify(signals, syscall.SIGTERM)

 	errs := make(chan error)
 	go func() {
 		errs <- runTests(ctx, config, files, cmdline)
 	}()

 	select {
 	case err := <-errs:
 		return err
 	case <-signals:
 		cancel()
 	}

 	return nil
 }

 func mustExist(filename string) {
 	_, err := os.Stat(filename)
 	if err != nil {
 		log.Fatalf("failed to stat %s: %v", filename, err)
 	}
 }

 func main() {
 	flag.Parse()

 	ctx := context.Background()

 	config, err := loadConfig(ctx, config)
 	if err != nil {
 		log.Fatal(err)
 	}

 	// Files is effectively an ordered map, so the order in which
 	// its contents are added is the order in which they'll be transferred
 	// later.
 	var files Files
 	if ramdiskImage != "" {
 		mustExist(ramdiskImage)
 		files.Set(ramdiskFilename, ramdiskImage)
 	}
 	if len(fvmImages) != 0 {
 		for _, image := range fvmImages {
 			mustExist(image)
 		}
 		files.Set(fvmFilename, fvmImages...)
 	}
 	if efiImage != "" {
 		mustExist(efiImage)
 		files.Set(efiFilename, efiImage)
 	}
 	if kerncImage != "" {
 		mustExist(kerncImage)
 		files.Set(kerncFilename, kerncImage)
 	}
 	if kernelImage == "" {
 		log.Fatal("-kernel is required")
 	}
 	mustExist(kernelImage)
 	files.Set(kernelFilename, kernelImage)

 	// Aggregate all cmdline flags.
 	cmdlineArgs := flag.Args()
 	if cmdline != "" {
 		b, err := ioutil.ReadFile(cmdline)
 		if err != nil {
 			log.Fatal("failed to read cmdline file: %v", err)
 		}
 		cmdlineArgs = append(cmdlineArgs, strings.Split(string(b), "\n")...)
 	}

 	if err := run(ctx, config, &files, cmdlineArgs); err != nil {
 		log.Fatal(err)
 	}
 }
	// Copyright 2017 The Fuchsia Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.
	package main

	import (
	"archive/tar"
	"bytes"
	"context"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"net"
	"os"
	"os/signal"
	"path"
	"path/filepath"
	"strings"
	"syscall"
	"time"

	"fuchsia.googlesource.com/infra/infra/netboot"
	"fuchsia.googlesource.com/infra/infra/pdu"
	"fuchsia.googlesource.com/infra/infra/retry"
	"fuchsia.googlesource.com/infra/infra/tftp"
	)

	const (
	netbootFilenamePrefix = "<<netboot>>"
	kernelFilename = netbootFilenamePrefix + "kernel.bin"
	ramdiskFilename = netbootFilenamePrefix + "ramdisk.bin"
	cmdlineFilename = netbootFilenamePrefix + "cmdline"

	imageFilenamePrefix = "<<image>>"
	efiFilename = imageFilenamePrefix + "efi.img"
	kerncFilename = imageFilenamePrefix + "kernc.img"
	fvmFilename = imageFilenamePrefix + "sparse.fvm"

	summaryFilename = "summary.json"
	)

	type stringsFlag []string

	func (s *stringsFlag) Set(val string) error {
	s = append(s, val)
	return nil
	}

	func (s *stringsFlag) String() string {
	if s == nil {
	return ""
	}
	return strings.Join([]string(*s), ", ")
	}

	var (
	config string // config file path
	kernelImage string // path to kernel image
	ramdiskImage string // path to ramdisk image
	efiImage string // path to efi image
	kerncImage string // path to kernc image
	fvmImages stringsFlag // list of paths to fvm images
	testdir string // path to test directory
	cmdline string // path to a file containing kernel cmdline args.
	outfile string // path to output file
	fileName string // name of the file in the test directory
	filePollInterval time.Duration // poll interval for file on device
	)

	func init() {
	flag.StringVar(&config, "config", "/etc/botanist/config.json", "config file path")
	flag.StringVar(&kernelImage, "kernel", "", "path to kernel image")
	flag.StringVar(&ramdiskImage, "ramdisk", "", "path to ramdisk image")
	flag.StringVar(&efiImage, "efi", "", "path to efi image to be paved")
	flag.StringVar(&kerncImage, "kernc", "", "path to kernc image to be paved")
	flag.Var(&fvmImages, "fvm", "path to a sparse fvm image to be paved (may be specified up to 4 times)")
	flag.StringVar(&cmdline, "cmdline", "", "path to a file containing command line arguments")
	flag.StringVar(&testdir, "test", "/test", "path to test directory")
	flag.StringVar(&outfile, "out", "output.tar", "path to output file")
	flag.StringVar(&fileName, "file-name", summaryFilename, "name of the file in the test directory")
	flag.DurationVar(&filePollInterval, "file-poll-interval", 1*time.Minute, "time between checking for summary.json on the target")
	}

	// Files is an ordered map for files which will be TFTP'd over to zedboot.
	type Files struct {
	remotes []string
	locals [][]string
	}

	// Set adds a configuration of what files to send for to the remote name.
	func (f *Files) Set(remote string, locals ...string) {
	f.remotes = append(f.remotes, remote)
	f.locals = append(f.locals, locals)
	}

	// Foreach calls a callback for each file to send in a filesMap.
	func (f *Files) Foreach(c func(remote, local string) error) error {
	for i := 0; i < len(f.remotes); i++ {
	for j := 0; j < len(f.locals[i]); j++ {
	if err := c(f.remotes[i], f.locals[i][j]); err != nil {
	return err
	}
	}
	}
	return nil
	}

	// Config contains the application configuration.
	type Config struct {
	// Nodname is the hostname of the hardware device we want to boot on.
	Nodename string `json:"nodename"`

	// PDU is the configuration for the PDU attached to the hardware device.
	PDU *pdu.Config `json:"pdu,omitempty"`
	}

	// Summary is the runtest summary output file format.
	type Summary struct {
	Tests []struct {
	Name string `json:"name"`
	OutputFile string `json:"output_file"`
	Result string `json:"result"`
	DataSinks map[string][]struct {
	Name string `json:"name"`
	File string `json:"file"`
	} `json:"data_sinks,omitempty"`
	} `json:"tests"`
	Outputs map[string]string `json:"outputs,omitempty"`
	}

	func writeFileToTar(client tftp.Client, tftpAddr net.UDPAddr, tw *tar.Writer, testDir string, outputFile string) error {
	writer, err := client.Receive(tftpAddr, path.Join(testDir, outputFile))
	if err != nil {
	return fmt.Errorf("failed to receive file %s: %v\n", outputFile, err)
	}
	hdr := &tar.Header{
	Name: outputFile,
	Size: writer.(tftp.Session).Size(),
	Mode: 0666,
	}
	if err := tw.WriteHeader(hdr); err != nil {
	return fmt.Errorf("failed to write file header: %v\n", err)
	}
	if _, err := writer.WriteTo(tw); err != nil {
	return fmt.Errorf("failed to write file content: %v\n", err)
	}

	return nil
	}

	func runTests(ctx context.Context, config Config, files Files, args []string) error {
	// Find the node address UDP address.
	n := netboot.NewClient(time.Second)

	var addr *net.UDPAddr
	var err error
	// We need to retry here because botanist might try to discover before
	// zedboot is fully ready, so the packet that's sent out doesn't result
	// in any reply. We don't need to wait between calls because Discover
	// already has a 1 minute timeout for reading a UDP packet from zedboot.
	err = retry.Retry(ctx, retry.WithMaxRetries(retry.NewConstantBackoff(time.Second), 60), func() error {
	addr, err = n.Discover(config.Nodename, false)
	return err
	})
	if err != nil {
	return fmt.Errorf("cannot find node \"%s\": %v\n", config.Nodename, err)
	}

	// Transfer kernel, ramdisk, and command line args onto the node.
	client := tftp.NewClient()
	tftpAddr := &net.UDPAddr{
	IP: addr.IP,
	Port: tftp.ClientPort,
	Zone: addr.Zone,
	}

	if err := transferFiles(ctx, client, tftpAddr, files, args); err != nil {
	return fmt.Errorf("cannot transfer files: %v\n", err)
	}

	// Set up log listener and dump kernel output to stdout.
	l, err := netboot.NewLogListener(config.Nodename)
	if err != nil {
	return fmt.Errorf("cannot listen: %v\n", err)
	}
	go func() {
	defer l.Close()
	log.Printf("starting log listener\n")
	for {
	data, err := l.Listen()
	if err != nil {
	continue
	}
	fmt.Print(data)
	select {
	case <-ctx.Done():
	return
	default:
	}
	}
	}()

	log.Printf("sending boot command\n")

	// Boot Fuchsia.
	if err := n.Boot(addr); err != nil {
	return fmt.Errorf("cannot boot: %v\n", err)
	}

	log.Printf("waiting for \"%s\"\n", fileName)

	// Poll for summary.json; this relies on runtest being executed using
	// autorun and it eventually producing the summary.json file.
	var buffer bytes.Buffer
	var writer io.WriterTo
	err = retry.Retry(ctx, retry.NewConstantBackoff(filePollInterval), func() error {
	writer, err = client.Receive(tftpAddr, path.Join(testdir, fileName))
	return err
	})
	if err != nil {
	return fmt.Errorf("timed out waiting for tests to complete: %v", err)
	}

	log.Printf("reading \"%s\"\n", fileName)

	if _, err := writer.WriteTo(&buffer); err != nil {
	return fmt.Errorf("failed to receive summary file: %v\n", err)
	}

	// Parse and save the summary.json file.
	var result Summary
	if err := json.Unmarshal(buffer.Bytes(), &result); err != nil {
	return fmt.Errorf("cannot unmarshall test results: %v\n", err)
	}

	file, err := os.OpenFile(outfile, os.O_WRONLY\|os.O_CREATE, 0666)
	if err != nil {
	return fmt.Errorf("failed to create file %s: %v\n", outfile, err)
	}
	tw := tar.NewWriter(file)
	defer tw.Close()

	hdr := &tar.Header{
	Name: summaryFilename,
	Size: int64(buffer.Len()),
	Mode: 0666,
	}
	if err := tw.WriteHeader(hdr); err != nil {
	return fmt.Errorf("failed to write summary header: %v\n", err)
	}
	if _, err := tw.Write(buffer.Bytes()); err != nil {
	return fmt.Errorf("failed to write summary content: %v\n", err)
	log.Fatal(err)
	}

	log.Printf("copying test output\n")

	// Copy test output from the node.
	for _, path := range result.Outputs {
	if err = writeFileToTar(client, tftpAddr, tw, testdir, path); err != nil {
	return err
	}
	}
	for _, test := range result.Tests {
	if err = writeFileToTar(client, tftpAddr, tw, testdir, test.OutputFile); err != nil {
	return err
	}
	// Copy data sinks if any are present.
	for _, sinks := range test.DataSinks {
	for _, sink := range sinks {
	if err = writeFileToTar(client, tftpAddr, tw, testdir, sink.File); err != nil {
	return err
	}
	}
	}
	}

	return nil
	}

	// transferFiles sends kernel, optionally ramdisk, and any command line args to
	// node.
	func transferFiles(ctx context.Context, client tftp.Client, addr net.UDPAddr, files *Files, cmdline []string) error {
	err := files.Foreach(func(remote, local string) error {
	file, err := os.Open(local)
	if err != nil {
	return fmt.Errorf("cannot open %s: %v\n", local, err)
	}
	defer file.Close()

	fi, err := file.Stat()
	if err != nil {
	return fmt.Errorf("cannot stat %s: %v\n", local, err)
	}
	// We need to retry because in the event of paving, TFTP might tell us
	// it's not ready yet.
	return retry.Retry(ctx, retry.WithMaxRetries(retry.NewConstantBackoff(time.Second), 60), func() error {
	fmt.Printf("attempting to send %s=%s\n", remote, filepath.Base(local))
	reader, err := client.Send(addr, remote, fi.Size())
	if err != nil {
	return fmt.Errorf("failed to send %s: %v\n", remote, err)
	}
	if _, err := reader.ReadFrom(file); err != nil {
	return fmt.Errorf("failed to send %s data: %v\n", local, err)
	}
	return nil
	})
	})
	if err != nil {
	return err
	}
	if len(cmdline) > 0 {
	var b bytes.Buffer
	for _, arg := range cmdline {
	fmt.Fprintf(&b, "%s\n", arg)
	}

	log.Printf("sending cmdline \"%s\"", b.String())

	reader, err := client.Send(addr, cmdlineFilename, int64(b.Len()))
	if err != nil {
	return fmt.Errorf("failed to send cmdline: %v\n", err)
	}
	if _, err := reader.ReadFrom(bytes.NewReader(b.Bytes())); err != nil {
	return fmt.Errorf("failed to read cmdline data: %v\n", err)
	}
	}
	return nil
	}

	func loadConfig(ctx context.Context, path string) (*Config, error) {
	file, err := os.Open(path)
	if err != nil {
	return nil, err
	}

	var config Config
	if err := json.NewDecoder(file).Decode(&config); err != nil {
	return nil, err
	}

	return &config, err
	}

	func run(ctx context.Context, config Config, files Files, cmdline []string) error {
	if config.PDU != nil {
	defer func() {
	log.Printf("rebooting the node \"%s\"\n", config.Nodename)

	if err := pdu.RebootDevice(config.PDU); err != nil {
	log.Fatalf("failed to reboot the device: %v", err)
	}
	}()
	}

	ctx, cancel := context.WithCancel(ctx)

	// Handle SIGTERM and make sure we send a reboot to the device.
	signals := make(chan os.Signal, 1)
	signal.Notify(signals, syscall.SIGTERM)

	errs := make(chan error)
	go func() {
	errs <- runTests(ctx, config, files, cmdline)
	}()

	select {
	case err := <-errs:
	return err
	case <-signals:
	cancel()
	}

	return nil
	}

	func mustExist(filename string) {
	_, err := os.Stat(filename)
	if err != nil {
	log.Fatalf("failed to stat %s: %v", filename, err)
	}
	}

	func main() {
	flag.Parse()

	ctx := context.Background()

	config, err := loadConfig(ctx, config)
	if err != nil {
	log.Fatal(err)
	}

	// Files is effectively an ordered map, so the order in which
	// its contents are added is the order in which they'll be transferred
	// later.
	var files Files
	if ramdiskImage != "" {
	mustExist(ramdiskImage)
	files.Set(ramdiskFilename, ramdiskImage)
	}
	if len(fvmImages) != 0 {
	for _, image := range fvmImages {
	mustExist(image)
	}
	files.Set(fvmFilename, fvmImages...)
	}
	if efiImage != "" {
	mustExist(efiImage)
	files.Set(efiFilename, efiImage)
	}
	if kerncImage != "" {
	mustExist(kerncImage)
	files.Set(kerncFilename, kerncImage)
	}
	if kernelImage == "" {
	log.Fatal("-kernel is required")
	}
	mustExist(kernelImage)
	files.Set(kernelFilename, kernelImage)

	// Aggregate all cmdline flags.
	cmdlineArgs := flag.Args()
	if cmdline != "" {
	b, err := ioutil.ReadFile(cmdline)
	if err != nil {
	log.Fatal("failed to read cmdline file: %v", err)
	}
	cmdlineArgs = append(cmdlineArgs, strings.Split(string(b), "\n")...)
	}

	if err := run(ctx, config, &files, cmdlineArgs); err != nil {
	log.Fatal(err)
	}
	}