Add temp dir cleanup on startup

Adding a reliable way of cleaning up the contents of temp dir to make
sure it doesn't pile up terraform binaries and grow in size with every
restart.

main.go

@@ -151,7 +151,12 @@ var (
 			Usage: "The comma separated list of ENVs which will be passed from controller to its managed modules during terraform run. " +
 				"The values should be set on the controller.",
 		},
-
+		&cli.BoolFlag{
+			Name:  "cleanup-temp-dir",
+			Value: false,
+			Usage: "If set, the OS temporary directory will be removed and re-created. This can help removing redundant terraform" +
+				"binaries and avoiding temp directory growing in size with every restart",
+		},
 		&cli.StringFlag{
 			Name:    "module-label-selector",
 			EnvVars: []string{"MODULE_LABEL_SELECTOR"},
@@ -411,6 +416,20 @@ preferences: {}
 
 }
 
+func cleanupTmpDir() {
+	tmpDir := os.TempDir()
+
+	err := os.RemoveAll(tmpDir)
+	if err != nil {
+		logger.Error("Error removing temporary directory:", err)
+	}
+
+	err = os.Mkdir(tmpDir, 0700)
+	if err != nil {
+		logger.Error("Error creating temporary directory:", err)
+	}
+}
+
 func main() {
 	app := &cli.App{
 		Name: "terraform-applier",
@@ -482,6 +501,11 @@ func run(c *cli.Context) {
 		}
 	}
 
+	// Cleanup temp directory if the corresponding flag is set
+	if c.Bool("cleanup-temp-dir") {
+		cleanupTmpDir()
+	}
+
 	// Find the requested version of terraform and log the version
 	// information
 	execPath, cleanup, err := findTerraformExecPath(ctx, terraformPath, terraformVersion)