feat: add machine readable flag

main.go

@@ -70,6 +70,11 @@ func main() {
 			Usage:  "Disable parallelization (on by default)",
 			EnvVar: "PLUGIN_PARALLEL",
 		},
+		cli.BoolFlag{
+			Name:   "readable",
+			Usage:  "Machine-readable output",
+			EnvVar: "PLUGIN_READABLE",
+		},
 	}
 
 	app.Version = Version
@@ -113,6 +118,7 @@ func run(c *cli.Context) error {
 			Color:      c.Bool("color"),
 			Debug:      c.Bool("debug"),
 			Parallel:   c.Bool("parallel"),
+			Readable:   c.Bool("readable"),
 		},
 	}
 

plugin.go

@@ -23,6 +23,7 @@ type (
 		Color      bool
 		Debug      bool
 		Parallel   bool
+		Readable   bool
 	}
 
 	// Plugin values
@@ -98,6 +99,10 @@ func pkBuild(config Config) *exec.Cmd {
 		args = append(args, "-debug")
 	}
 
+	if config.Readable {
+		args = append(args, "-machine-readable")
+	}
+
 	args = append(args, config.Template)
 	return exec.Command(
 		"packer",

plugin_test.go

@@ -103,6 +103,16 @@ func Test_pkBuild(t *testing.T) {
 			},
 			want: exec.Command("packer", "build", "-parallel=true", "-color=true", "-debug", "foo.json"),
 		},
+		{
+			name: "add machine readable flag",
+			args: args{
+				config: Config{
+					Template: "foo.json",
+					Readable: true,
+				},
+			},
+			want: exec.Command("packer", "build", "-machine-readable", "foo.json"),
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {