open-nomad/client/driver/executor/exec_basic.go

149 lines
3.4 KiB
Go

package executor
import (
"bytes"
"encoding/json"
"fmt"
"os"
"os/exec"
"path/filepath"
"strings"
"github.com/hashicorp/nomad/client/allocdir"
"github.com/hashicorp/nomad/client/driver/args"
"github.com/hashicorp/nomad/client/driver/environment"
"github.com/hashicorp/nomad/client/driver/spawn"
"github.com/hashicorp/nomad/nomad/structs"
)
// BasicExecutor should work everywhere, and as a result does not include
// any resource restrictions or runas capabilities.
type BasicExecutor struct {
cmd exec.Cmd
spawn *spawn.Spawner
taskName string
taskDir string
allocDir string
}
// TODO: Have raw_exec use this as well.
func NewBasicExecutor() Executor {
return &BasicExecutor{}
}
func (e *BasicExecutor) Limit(resources *structs.Resources) error {
if resources == nil {
return errNoResources
}
return nil
}
func (e *BasicExecutor) ConfigureTaskDir(taskName string, alloc *allocdir.AllocDir) error {
taskDir, ok := alloc.TaskDirs[taskName]
if !ok {
fmt.Errorf("Couldn't find task directory for task %v", taskName)
}
e.cmd.Dir = taskDir
e.taskDir = taskDir
e.taskName = taskName
e.allocDir = alloc.AllocDir
return nil
}
func (e *BasicExecutor) Start() error {
// Parse the commands arguments and replace instances of Nomad environment
// variables.
envVars, err := environment.ParseFromList(e.cmd.Env)
if err != nil {
return err
}
parsedPath, err := args.ParseAndReplace(e.cmd.Path, envVars.Map())
if err != nil {
return err
} else if len(parsedPath) != 1 {
return fmt.Errorf("couldn't properly parse command path: %v", e.cmd.Path)
}
e.cmd.Path = parsedPath[0]
combined := strings.Join(e.cmd.Args, " ")
parsed, err := args.ParseAndReplace(combined, envVars.Map())
if err != nil {
return err
}
e.cmd.Args = parsed
spawnState := filepath.Join(e.allocDir, fmt.Sprintf("%s_%s", e.taskName, "exit_status"))
e.spawn = spawn.NewSpawner(spawnState)
e.spawn.SetCommand(&e.cmd)
e.spawn.SetLogs(&spawn.Logs{
Stdout: filepath.Join(e.taskDir, allocdir.TaskLocal, fmt.Sprintf("%v.stdout", e.taskName)),
Stderr: filepath.Join(e.taskDir, allocdir.TaskLocal, fmt.Sprintf("%v.stderr", e.taskName)),
Stdin: os.DevNull,
})
return e.spawn.Spawn(nil)
}
func (e *BasicExecutor) Open(id string) error {
var spawn spawn.Spawner
dec := json.NewDecoder(strings.NewReader(id))
if err := dec.Decode(&spawn); err != nil {
return fmt.Errorf("Failed to parse id: %v", err)
}
// Setup the executor.
e.spawn = &spawn
return nil
}
func (e *BasicExecutor) Wait() error {
code, err := e.spawn.Wait()
if err != nil {
return err
}
if code != 0 {
return fmt.Errorf("Task exited with code: %d", code)
}
return nil
}
func (e *BasicExecutor) ID() (string, error) {
if e.spawn == nil {
return "", fmt.Errorf("Process was never started")
}
var buffer bytes.Buffer
enc := json.NewEncoder(&buffer)
if err := enc.Encode(e.spawn); err != nil {
return "", fmt.Errorf("Failed to serialize id: %v", err)
}
return buffer.String(), nil
}
func (e *BasicExecutor) Shutdown() error {
proc, err := os.FindProcess(e.spawn.UserPid)
if err != nil {
return fmt.Errorf("Failed to find user processes %v: %v", e.spawn.UserPid, err)
}
return proc.Signal(os.Interrupt)
}
func (e *BasicExecutor) ForceStop() error {
proc, err := os.FindProcess(e.spawn.UserPid)
if err != nil {
return fmt.Errorf("Failed to find user processes %v: %v", e.spawn.UserPid, err)
}
return proc.Kill()
}
func (e *BasicExecutor) Command() *exec.Cmd {
return &e.cmd
}