Merge pull request #4788 from hashicorp/r-clientv2-exec

drivers/exec: add exec implementation

client/driver/executor/executor.go

@@ -276,12 +276,12 @@ func (e *UniversalExecutor) Launch(command *ExecCommand) (*ProcessState, error)
 	e.childCmd.Stderr = stderr
 
 	// Look up the binary path and make it executable
-	absPath, err := e.lookupBin(command.Cmd)
+	absPath, err := lookupBin(command.TaskDir, command.Cmd)
 	if err != nil {
 		return nil, err
 	}
 
-	if err := e.makeExecutable(absPath); err != nil {
+	if err := makeExecutable(absPath); err != nil {
 		return nil, err
 	}
 
@@ -476,18 +476,42 @@ func (e *UniversalExecutor) Shutdown(signal string, grace time.Duration) error {
 	return nil
 }
 
+// Signal sends the passed signal to the task
+func (e *UniversalExecutor) Signal(s os.Signal) error {
+	if e.childCmd.Process == nil {
+		return fmt.Errorf("Task not yet run")
+	}
+
+	e.logger.Debug("sending signal to PID", "signal", s, "pid", e.childCmd.Process.Pid)
+	err := e.childCmd.Process.Signal(s)
+	if err != nil {
+		e.logger.Error("sending signal failed", "signal", s, "error", err)
+		return err
+	}
+
+	return nil
+}
+
+func (e *UniversalExecutor) Stats() (*cstructs.TaskResourceUsage, error) {
+	pidStats, err := e.pidCollector.pidStats()
+	if err != nil {
+		return nil, err
+	}
+	return aggregatedResourceUsage(e.systemCpuStats, pidStats), nil
+}
+
 // lookupBin looks for path to the binary to run by looking for the binary in
 // the following locations, in-order: task/local/, task/, based on host $PATH.
 // The return path is absolute.
-func (e *UniversalExecutor) lookupBin(bin string) (string, error) {
+func lookupBin(taskDir string, bin string) (string, error) {
 	// Check in the local directory
-	local := filepath.Join(e.commandCfg.TaskDir, allocdir.TaskLocal, bin)
+	local := filepath.Join(taskDir, allocdir.TaskLocal, bin)
 	if _, err := os.Stat(local); err == nil {
 		return local, nil
 	}
 
 	// Check at the root of the task's directory
-	root := filepath.Join(e.commandCfg.TaskDir, bin)
+	root := filepath.Join(taskDir, bin)
 	if _, err := os.Stat(root); err == nil {
 		return root, nil
 	}
@@ -501,7 +525,7 @@ func (e *UniversalExecutor) lookupBin(bin string) (string, error) {
 }
 
 // makeExecutable makes the given file executable for root,group,others.
-func (e *UniversalExecutor) makeExecutable(binPath string) error {
+func makeExecutable(binPath string) error {
 	if runtime.GOOS == "windows" {
 		return nil
 	}
@@ -524,27 +548,3 @@ func (e *UniversalExecutor) makeExecutable(binPath string) error {
 	}
 	return nil
 }
-
-// Signal sends the passed signal to the task
-func (e *UniversalExecutor) Signal(s os.Signal) error {
-	if e.childCmd.Process == nil {
-		return fmt.Errorf("Task not yet run")
-	}
-
-	e.logger.Debug("sending signal to PID", "signal", s, "pid", e.childCmd.Process.Pid)
-	err := e.childCmd.Process.Signal(s)
-	if err != nil {
-		e.logger.Error("sending signal failed", "signal", s, "error", err)
-		return err
-	}
-
-	return nil
-}
-
-func (e *UniversalExecutor) Stats() (*cstructs.TaskResourceUsage, error) {
-	pidStats, err := e.pidCollector.pidStats()
-	if err != nil {
-		return nil, err
-	}
-	return aggregatedResourceUsage(e.systemCpuStats, pidStats), nil
-}

client/driver/executor/executor_linux.go

@@ -101,6 +101,10 @@ func (l *LibcontainerExecutor) Launch(command *ExecCommand) (*ProcessState, erro
 		return nil, fmt.Errorf("unable to find the nomad binary: %v", err)
 	}
 
+	if command.Resources == nil {
+		command.Resources = &Resources{}
+	}
+
 	l.command = command
 
 	// Move to the root cgroup until process is started
@@ -129,7 +133,26 @@ func (l *LibcontainerExecutor) Launch(command *ExecCommand) (*ProcessState, erro
 	}
 	l.container = container
 
-	combined := append([]string{command.Cmd}, command.Args...)
+	// Look up the binary path and make it executable
+	absPath, err := lookupBin(command.TaskDir, command.Cmd)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := makeExecutable(absPath); err != nil {
+		return nil, err
+	}
+
+	path := absPath
+
+	// Determine the path to run as it may have to be relative to the chroot.
+	rel, err := filepath.Rel(command.TaskDir, path)
+	if err != nil {
+		return nil, fmt.Errorf("failed to determine relative path base=%q target=%q: %v", command.TaskDir, path, err)
+	}
+	path = rel
+
+	combined := append([]string{path}, command.Args...)
 	stdout, err := command.Stdout()
 	if err != nil {
 		return nil, err