find

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• Variables

Variables

var Cmd = &cli.Cmd[findArgs]{
	Name:        "find",
	Usage:       "find [IMAGE PATH]",
	Description: "find data hidden inside an image",
	Examples: []cli.Example{
		{
			Description: "find hidden data from inside 'img.png'",
			Args:        []string{"img.png"},
			Output:      "Here's the hidden data",
		},
		{
			Description: "searching for hidden data in 'img.png' fails",
			Args:        []string{"img.png"},
			Error:       errors.New("magic number does not match"),
		},
	},
	ParseArgs: func(args []string) (findArgs, error) {
		if len(args) != 1 {
			return findArgs{}, errors.New("invalid argument count")
		}

		if !strings.HasSuffix(args[0], ".png") {
			return findArgs{}, errors.New("only png images are supported")
		}

		return findArgs{
			imagePath: args[0],
		}, nil
	},
	Fn: func(args findArgs) error {
		f, err := os.Open(args.imagePath)
		if err != nil {
			return fmt.Errorf("failed to read in an image file: %w", err)
		}
		defer f.Close()

		inImage, err := png.Decode(f)
		if err != nil {
			return fmt.Errorf("failed to decode png file: %w", err)
		}

		img, ok := inImage.(*image.NRGBA)
		if !ok {
			return fmt.Errorf("invalid image format: %T", img)
		}

		got, err := findData(img)
		if err != nil {
			return fmt.Errorf("failed to get hidden data: %w", err)
		}

		fmt.Print(string(got))
		return nil
	},
}

Cmd is the find command that searches the given image for data hidden using the hide command