fix: ctx should cancel image pull on run

This patch fixes the context cancellation
behaviour for the `runContainer` function,
specifically the `createContainer` function.
It delays stripping the `cancel` from the context
passed into the `runContainer` function so that
the `createContainer` function can be cancelled
gracefully by a SIGTERM/SIGINT.

This is especially true when the requested image
does not exist and `docker run` needs to `pull`
the image before creating the container.

Although this patch does fix gracefully cancelling
the `runContainer` function it does not address
the root cause. Some functions in the call path
are not context aware, such as `pullImage`.
Future work would still be necessary to ensure
a consistent behaviour in the CLI.

Signed-off-by: Alano Terblanche <[email protected]>

cli/command/container/run.go

@@ -118,8 +118,6 @@ func runRun(ctx context.Context, dockerCli command.Cli, flags *pflag.FlagSet, ro
 
 //nolint:gocyclo
 func runContainer(ctx context.Context, dockerCli command.Cli, runOpts *runOptions, copts *containerOptions, containerCfg *containerConfig) error {
-	ctx = context.WithoutCancel(ctx)
-
 	config := containerCfg.Config
 	stdout, stderr := dockerCli.Out(), dockerCli.Err()
 	apiClient := dockerCli.Client()
@@ -141,9 +139,6 @@ func runContainer(ctx context.Context, dockerCli command.Cli, runOpts *runOption
 		config.StdinOnce = false
 	}
 
-	ctx, cancelFun := context.WithCancel(ctx)
-	defer cancelFun()
-
 	containerID, err := createContainer(ctx, dockerCli, containerCfg, &runOpts.createOptions)
 	if err != nil {
 		return toStatusError(err)
@@ -159,6 +154,9 @@ func runContainer(ctx context.Context, dockerCli command.Cli, runOpts *runOption
 		defer signal.StopCatch(sigc)
 	}
 
+	ctx, cancelFun := context.WithCancel(context.WithoutCancel(ctx))
+	defer cancelFun()
+
 	var (
 		waitDisplayID chan struct{}
 		errCh         chan error