From e026d6e80a158244c8a5cfcb65f047633d7bc9ce Mon Sep 17 00:00:00 2001
From: Michael Schurter <schmichael@hashicorp.com>
Date: Mon, 15 Oct 2018 20:06:35 -0700
Subject: [PATCH] tr: remove unused DriverHandle interface

was causing typed nil interface panics and served no purpose
---
 .../taskrunner/interfaces/handle.go           | 36 -------------------
 client/allocrunner/taskrunner/task_runner.go  |  3 +-
 .../taskrunner/task_runner_getters.go         |  3 +-
 3 files changed, 2 insertions(+), 40 deletions(-)

diff --git a/client/allocrunner/taskrunner/interfaces/handle.go b/client/allocrunner/taskrunner/interfaces/handle.go
index a0737c74f..3fafaba15 100644
--- a/client/allocrunner/taskrunner/interfaces/handle.go
+++ b/client/allocrunner/taskrunner/interfaces/handle.go
@@ -1,45 +1,9 @@
 package interfaces
 
 import (
-	"context"
 	"time"
-
-	cstructs "github.com/hashicorp/nomad/client/structs"
-	"github.com/hashicorp/nomad/nomad/structs"
-	"github.com/hashicorp/nomad/plugins/drivers"
 )
 
-// DriverHandle wraps operations to a driver such that they are operated on a specific
-// task
-type DriverHandle interface {
-	// ID returns the task ID
-	ID() string
-
-	// WaitCh is used to return a channel used to wait for task completion
-	WaitCh(context.Context) (<-chan *drivers.ExitResult, error)
-
-	// Update is used to update the task if possible and update task related
-	// configurations.
-	Update(task *structs.Task) error
-
-	// Kill is used to stop the task
-	Kill() error
-
-	// Stats returns aggregated stats of the driver
-	Stats() (*cstructs.TaskResourceUsage, error)
-
-	// Signal is used to send a signal to the task
-	Signal(s string) error
-
-	// ScriptExecutor is an interface used to execute commands such as
-	// health check scripts in the a DriverHandle's context.
-	ScriptExecutor
-
-	// Network returns the driver's network or nil if the driver did not
-	// create a network.
-	Network() *cstructs.DriverNetwork
-}
-
 // ScriptExecutor is an interface that supports Exec()ing commands in the
 // driver's context. Split out of DriverHandle to ease testing.
 type ScriptExecutor interface {
diff --git a/client/allocrunner/taskrunner/task_runner.go b/client/allocrunner/taskrunner/task_runner.go
index c3a49c94a..49c560b50 100644
--- a/client/allocrunner/taskrunner/task_runner.go
+++ b/client/allocrunner/taskrunner/task_runner.go
@@ -15,7 +15,6 @@ import (
 	"github.com/hashicorp/hcl2/hcldec"
 	"github.com/hashicorp/nomad/client/allocdir"
 	"github.com/hashicorp/nomad/client/allocrunner/interfaces"
-	tinterfaces "github.com/hashicorp/nomad/client/allocrunner/taskrunner/interfaces"
 	"github.com/hashicorp/nomad/client/allocrunner/taskrunner/restarts"
 	"github.com/hashicorp/nomad/client/allocrunner/taskrunner/state"
 	"github.com/hashicorp/nomad/client/config"
@@ -548,7 +547,7 @@ func (tr *TaskRunner) initDriver() error {
 // handleDestroy will retry with an exponential backoff and will give up at a
 // given limit. It returns whether the task was destroyed and the error
 // associated with the last kill attempt.
-func (tr *TaskRunner) handleDestroy(handle tinterfaces.DriverHandle) (destroyed bool, err error) {
+func (tr *TaskRunner) handleDestroy(handle *DriverHandle) (destroyed bool, err error) {
 	// Cap the number of times we attempt to kill the task.
 	for i := 0; i < killFailureLimit; i++ {
 		if err = handle.Kill(); err != nil {
diff --git a/client/allocrunner/taskrunner/task_runner_getters.go b/client/allocrunner/taskrunner/task_runner_getters.go
index 8a5661be0..61eaf9711 100644
--- a/client/allocrunner/taskrunner/task_runner_getters.go
+++ b/client/allocrunner/taskrunner/task_runner_getters.go
@@ -1,7 +1,6 @@
 package taskrunner
 
 import (
-	"github.com/hashicorp/nomad/client/allocrunner/taskrunner/interfaces"
 	"github.com/hashicorp/nomad/nomad/structs"
 )
 
@@ -51,7 +50,7 @@ func (tr *TaskRunner) setVaultToken(token string) {
 
 // getDriverHandle returns a driver handle and its result proxy. Use the
 // result proxy instead of the handle's WaitCh.
-func (tr *TaskRunner) getDriverHandle() interfaces.DriverHandle {
+func (tr *TaskRunner) getDriverHandle() *DriverHandle {
 	tr.handleLock.Lock()
 	defer tr.handleLock.Unlock()
 	return tr.handle