all flag use EnvVars (#237)

pkg/app.go

@@ -70,36 +70,42 @@ OPTIONS:
 			Usage:  "For CIS-DI-0010. You can add acceptable file extensions. e.g) -ae pem -ae log",
 		},
 		cli.StringFlag{
-			Name:  "format, f",
-			Value: "",
-			Usage: "format (json)",
+			Name:   "format, f",
+			Value:  "",
+			EnvVar: "DOCKLE_OUTPUT_FORMAT",
+			Usage:  "output format (list, json, sarif)",
 		},
 		cli.StringFlag{
-			Name:  "output, o",
-			Usage: "output file name",
+			Name:   "output, o",
+			EnvVar: "DOCKLE_OUTPUT_FILE",
+			Usage:  "output file name",
 		},
 		cli.IntFlag{
-			Name:  "exit-code, c",
-			Usage: "exit code when alert were found",
-			Value: 0,
+			Name:   "exit-code, c",
+			Value:  0,
+			EnvVar: "DOCKLE_EXIT_CODE",
+			Usage:  "exit code when alert were found",
 		},
 		cli.StringFlag{
-			Name:  "exit-level, l",
-			Usage: "change ABEND level when use exit-code=1",
-			Value: "WARN",
+			Name:   "exit-level, l",
+			Value:  "WARN",
+			EnvVar: "DOCKLE_EXIT_LEVEL",
+			Usage:  "change ABEND level when use exit-code=1",
 		},
 		cli.BoolFlag{
-			Name:  "debug, d",
-			Usage: "debug mode",
+			Name:   "debug, d",
+			EnvVar: "DOCKLE_DEBUG",
+			Usage:  "debug mode",
 		},
 		cli.BoolFlag{
-			Name:  "quiet, q",
-			Usage: "suppress log output",
+			Name:   "quiet, q",
+			EnvVar: "DOCKLE_QUIET",
+			Usage:  "suppress log output",
 		},
 		cli.BoolFlag{
 			Name:   "no-color",
 			EnvVar: "NO_COLOR",
-			Usage:  "suppress log output",
+			Usage:  "disabling color output",
 		},
 		cli.BoolFlag{
 			Name:   "version-check",
@@ -117,7 +123,7 @@ OPTIONS:
 		cli.BoolFlag{
 			Name:   "use-xdg, x",
 			EnvVar: "USE_XDG",
-			Usage:  "Docker daemon host file  XDG_RUNTIME_DIR",
+			Usage:  "Docker daemon host file XDG_RUNTIME_DIR",
 		},
 		cli.StringFlag{
 			Name:   "host",