open-nomad/client/driver/java.go

422 lines
12 KiB
Go

package driver
import (
"bytes"
"encoding/json"
"fmt"
"log"
"os"
"os/exec"
"path/filepath"
"runtime"
"strings"
"syscall"
"time"
"github.com/hashicorp/go-multierror"
"github.com/hashicorp/go-plugin"
"github.com/mitchellh/mapstructure"
"github.com/hashicorp/nomad/client/allocdir"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/client/driver/executor"
dstructs "github.com/hashicorp/nomad/client/driver/structs"
"github.com/hashicorp/nomad/client/fingerprint"
cstructs "github.com/hashicorp/nomad/client/structs"
"github.com/hashicorp/nomad/helper/discover"
"github.com/hashicorp/nomad/helper/fields"
"github.com/hashicorp/nomad/nomad/structs"
)
const (
// The key populated in Node Attributes to indicate presence of the Java
// driver
javaDriverAttr = "driver.java"
)
// JavaDriver is a simple driver to execute applications packaged in Jars.
// It literally just fork/execs tasks with the java command.
type JavaDriver struct {
DriverContext
fingerprint.StaticFingerprinter
}
type JavaDriverConfig struct {
JarPath string `mapstructure:"jar_path"`
JvmOpts []string `mapstructure:"jvm_options"`
Args []string `mapstructure:"args"`
}
// javaHandle is returned from Start/Open as a handle to the PID
type javaHandle struct {
pluginClient *plugin.Client
userPid int
executor executor.Executor
isolationConfig *dstructs.IsolationConfig
taskDir string
allocDir *allocdir.AllocDir
killTimeout time.Duration
maxKillTimeout time.Duration
version string
logger *log.Logger
waitCh chan *dstructs.WaitResult
doneCh chan struct{}
}
// NewJavaDriver is used to create a new exec driver
func NewJavaDriver(ctx *DriverContext) Driver {
return &JavaDriver{DriverContext: *ctx}
}
// Validate is used to validate the driver configuration
func (d *JavaDriver) Validate(config map[string]interface{}) error {
fd := &fields.FieldData{
Raw: config,
Schema: map[string]*fields.FieldSchema{
"jar_path": &fields.FieldSchema{
Type: fields.TypeString,
Required: true,
},
"jvm_options": &fields.FieldSchema{
Type: fields.TypeArray,
},
"args": &fields.FieldSchema{
Type: fields.TypeArray,
},
},
}
if err := fd.Validate(); err != nil {
return err
}
return nil
}
func (d *JavaDriver) Fingerprint(cfg *config.Config, node *structs.Node) (bool, error) {
// Get the current status so that we can log any debug messages only if the
// state changes
_, currentlyEnabled := node.Attributes[javaDriverAttr]
// Only enable if we are root and cgroups are mounted when running on linux systems.
if runtime.GOOS == "linux" && (syscall.Geteuid() != 0 || !d.cgroupsMounted(node)) {
if currentlyEnabled {
d.logger.Printf("[DEBUG] driver.java: root priviledges and mounted cgroups required on linux, disabling")
}
delete(node.Attributes, "driver.java")
return false, nil
}
// Find java version
var out bytes.Buffer
var erOut bytes.Buffer
cmd := exec.Command("java", "-version")
cmd.Stdout = &out
cmd.Stderr = &erOut
err := cmd.Run()
if err != nil {
// assume Java wasn't found
delete(node.Attributes, javaDriverAttr)
return false, nil
}
// 'java -version' returns output on Stderr typically.
// Check stdout, but it's probably empty
var infoString string
if out.String() != "" {
infoString = out.String()
}
if erOut.String() != "" {
infoString = erOut.String()
}
if infoString == "" {
if currentlyEnabled {
d.logger.Println("[WARN] driver.java: error parsing Java version information, aborting")
}
delete(node.Attributes, javaDriverAttr)
return false, nil
}
// Assume 'java -version' returns 3 lines:
// java version "1.6.0_36"
// OpenJDK Runtime Environment (IcedTea6 1.13.8) (6b36-1.13.8-0ubuntu1~12.04)
// OpenJDK 64-Bit Server VM (build 23.25-b01, mixed mode)
// Each line is terminated by \n
info := strings.Split(infoString, "\n")
versionString := info[0]
versionString = strings.TrimPrefix(versionString, "java version ")
versionString = strings.Trim(versionString, "\"")
node.Attributes[javaDriverAttr] = "1"
node.Attributes["driver.java.version"] = versionString
node.Attributes["driver.java.runtime"] = info[1]
node.Attributes["driver.java.vm"] = info[2]
return true, nil
}
func (d *JavaDriver) Start(ctx *ExecContext, task *structs.Task) (DriverHandle, error) {
var driverConfig JavaDriverConfig
if err := mapstructure.WeakDecode(task.Config, &driverConfig); err != nil {
return nil, err
}
// Set the host environment variables.
filter := strings.Split(d.config.ReadDefault("env.blacklist", config.DefaultEnvBlacklist), ",")
d.taskEnv.AppendHostEnvvars(filter)
taskDir, ok := ctx.AllocDir.TaskDirs[d.DriverContext.taskName]
if !ok {
return nil, fmt.Errorf("Could not find task directory for task: %v", d.DriverContext.taskName)
}
if driverConfig.JarPath == "" {
return nil, fmt.Errorf("jar_path must be specified")
}
args := []string{}
// Look for jvm options
if len(driverConfig.JvmOpts) != 0 {
d.logger.Printf("[DEBUG] driver.java: found JVM options: %s", driverConfig.JvmOpts)
args = append(args, driverConfig.JvmOpts...)
}
// Build the argument list.
args = append(args, "-jar", driverConfig.JarPath)
if len(driverConfig.Args) != 0 {
args = append(args, driverConfig.Args...)
}
bin, err := discover.NomadExecutable()
if err != nil {
return nil, fmt.Errorf("unable to find the nomad binary: %v", err)
}
pluginLogFile := filepath.Join(taskDir, fmt.Sprintf("%s-executor.out", task.Name))
pluginConfig := &plugin.ClientConfig{
Cmd: exec.Command(bin, "executor", pluginLogFile),
}
execIntf, pluginClient, err := createExecutor(pluginConfig, d.config.LogOutput, d.config)
if err != nil {
return nil, err
}
executorCtx := &executor.ExecutorContext{
TaskEnv: d.taskEnv,
Driver: "java",
AllocDir: ctx.AllocDir,
AllocID: ctx.AllocID,
ChrootEnv: d.config.ChrootEnv,
Task: task,
}
absPath, err := GetAbsolutePath("java")
if err != nil {
return nil, err
}
ps, err := execIntf.LaunchCmd(&executor.ExecCommand{
Cmd: absPath,
Args: args,
FSIsolation: true,
ResourceLimits: true,
User: getExecutorUser(task),
}, executorCtx)
if err != nil {
pluginClient.Kill()
return nil, err
}
d.logger.Printf("[DEBUG] driver.java: started process with pid: %v", ps.Pid)
// Return a driver handle
maxKill := d.DriverContext.config.MaxKillTimeout
h := &javaHandle{
pluginClient: pluginClient,
executor: execIntf,
userPid: ps.Pid,
isolationConfig: ps.IsolationConfig,
taskDir: taskDir,
allocDir: ctx.AllocDir,
killTimeout: GetKillTimeout(task.KillTimeout, maxKill),
maxKillTimeout: maxKill,
version: d.config.Version,
logger: d.logger,
doneCh: make(chan struct{}),
waitCh: make(chan *dstructs.WaitResult, 1),
}
if err := h.executor.SyncServices(consulContext(d.config, "")); err != nil {
d.logger.Printf("[ERR] driver.java: error registering services with consul for task: %q: %v", task.Name, err)
}
go h.run()
return h, nil
}
// cgroupsMounted returns true if the cgroups are mounted on a system otherwise
// returns false
func (d *JavaDriver) cgroupsMounted(node *structs.Node) bool {
_, ok := node.Attributes["unique.cgroup.mountpoint"]
return ok
}
type javaId struct {
Version string
KillTimeout time.Duration
MaxKillTimeout time.Duration
PluginConfig *PluginReattachConfig
IsolationConfig *dstructs.IsolationConfig
TaskDir string
AllocDir *allocdir.AllocDir
UserPid int
}
func (d *JavaDriver) Open(ctx *ExecContext, handleID string) (DriverHandle, error) {
id := &javaId{}
if err := json.Unmarshal([]byte(handleID), id); err != nil {
return nil, fmt.Errorf("Failed to parse handle '%s': %v", handleID, err)
}
pluginConfig := &plugin.ClientConfig{
Reattach: id.PluginConfig.PluginConfig(),
}
exec, pluginClient, err := createExecutor(pluginConfig, d.config.LogOutput, d.config)
if err != nil {
merrs := new(multierror.Error)
merrs.Errors = append(merrs.Errors, err)
d.logger.Println("[ERR] driver.java: error connecting to plugin so destroying plugin pid and user pid")
if e := destroyPlugin(id.PluginConfig.Pid, id.UserPid); e != nil {
merrs.Errors = append(merrs.Errors, fmt.Errorf("error destroying plugin and userpid: %v", e))
}
if id.IsolationConfig != nil {
ePid := pluginConfig.Reattach.Pid
if e := executor.ClientCleanup(id.IsolationConfig, ePid); e != nil {
merrs.Errors = append(merrs.Errors, fmt.Errorf("destroying resource container failed: %v", e))
}
}
if e := ctx.AllocDir.UnmountAll(); e != nil {
merrs.Errors = append(merrs.Errors, e)
}
return nil, fmt.Errorf("error connecting to plugin: %v", merrs.ErrorOrNil())
}
ver, _ := exec.Version()
d.logger.Printf("[DEBUG] driver.java: version of executor: %v", ver.Version)
// Return a driver handle
h := &javaHandle{
pluginClient: pluginClient,
executor: exec,
userPid: id.UserPid,
isolationConfig: id.IsolationConfig,
taskDir: id.TaskDir,
allocDir: id.AllocDir,
logger: d.logger,
version: id.Version,
killTimeout: id.KillTimeout,
maxKillTimeout: id.MaxKillTimeout,
doneCh: make(chan struct{}),
waitCh: make(chan *dstructs.WaitResult, 1),
}
if err := h.executor.SyncServices(consulContext(d.config, "")); err != nil {
d.logger.Printf("[ERR] driver.java: error registering services with consul: %v", err)
}
go h.run()
return h, nil
}
func (h *javaHandle) ID() string {
id := javaId{
Version: h.version,
KillTimeout: h.killTimeout,
MaxKillTimeout: h.maxKillTimeout,
PluginConfig: NewPluginReattachConfig(h.pluginClient.ReattachConfig()),
UserPid: h.userPid,
TaskDir: h.taskDir,
AllocDir: h.allocDir,
IsolationConfig: h.isolationConfig,
}
data, err := json.Marshal(id)
if err != nil {
h.logger.Printf("[ERR] driver.java: failed to marshal ID to JSON: %s", err)
}
return string(data)
}
func (h *javaHandle) WaitCh() chan *dstructs.WaitResult {
return h.waitCh
}
func (h *javaHandle) Update(task *structs.Task) error {
// Store the updated kill timeout.
h.killTimeout = GetKillTimeout(task.KillTimeout, h.maxKillTimeout)
h.executor.UpdateTask(task)
// Update is not possible
return nil
}
func (h *javaHandle) Signal(s os.Signal) error {
return nil
}
func (h *javaHandle) Kill() error {
if err := h.executor.ShutDown(); err != nil {
if h.pluginClient.Exited() {
return nil
}
return fmt.Errorf("executor Shutdown failed: %v", err)
}
select {
case <-h.doneCh:
return nil
case <-time.After(h.killTimeout):
if h.pluginClient.Exited() {
return nil
}
if err := h.executor.Exit(); err != nil {
return fmt.Errorf("executor Exit failed: %v", err)
}
return nil
}
}
func (h *javaHandle) Stats() (*cstructs.TaskResourceUsage, error) {
return h.executor.Stats()
}
func (h *javaHandle) run() {
ps, err := h.executor.Wait()
close(h.doneCh)
if ps.ExitCode == 0 && err != nil {
if h.isolationConfig != nil {
ePid := h.pluginClient.ReattachConfig().Pid
if e := executor.ClientCleanup(h.isolationConfig, ePid); e != nil {
h.logger.Printf("[ERR] driver.java: destroying resource container failed: %v", e)
}
} else {
if e := killProcess(h.userPid); e != nil {
h.logger.Printf("[ERR] driver.java: error killing user process: %v", e)
}
}
if e := h.allocDir.UnmountAll(); e != nil {
h.logger.Printf("[ERR] driver.java: unmounting dev,proc and alloc dirs failed: %v", e)
}
}
h.waitCh <- &dstructs.WaitResult{ExitCode: ps.ExitCode, Signal: ps.Signal, Err: err}
close(h.waitCh)
// Remove services
if err := h.executor.DeregisterServices(); err != nil {
h.logger.Printf("[ERR] driver.java: failed to kill the deregister services: %v", err)
}
h.executor.Exit()
h.pluginClient.Kill()
}