imagefilter

type Filter interface {
	// Apply applies the image filter to an image and returns the new image.
	Apply(*caddy.Replacer, image.Image) (image.Image, error)
}

type FilterFactory interface {
	// Name returns the name of the filter, which is also the directive used in the image filter
	// block. It should be in lower case.
	Name() string

	// New initialises and returns the image filter instance.
	New(...string) (Filter, error)

	// Unmarshal decodes JSON configuration and returns the corresponding image filter instance.
	Unmarshal([]byte) (Filter, error)
}

type ImageFilter struct {
	// The file system implementation to use. By default, Caddy uses the local disk file system.
	FileSystemRaw json.RawMessage `json:"file_system,omitempty" caddy:"namespace=caddy.fs inline_key=backend"`

	// Filters is a map of initialized image filters. Keys have the form
	// "<position>_<image filter name>", where <position> specifies the order in which the image
	// filters will be applied.
	Filters filters `json:"filters,omitempty"`

	// Root is the path to the root of the site. Default is `{http.vars.root}` if set, or current
	// working directory otherwise.
	Root string `json:"root,omitempty"`

	// FilterOrder is a slice of strings in the form "<position>_<image filter name>". Each entry
	// should have a corresponding entry in the Filters map.
	FilterOrder []string `json:"filter_order,omitempty"`

	// JpegQuality determines the quality of jpeg encoding after the filters are applied. It ranges
	// from 1 to 100 inclusive, higher is better. Default is 75.
	JpegQuality int `json:"jpeg_quality,omitempty"`

	// PngCompression determines the compression of png images. Possible values are:
	//   * 0: Default compression
	//   * -1: no compression
	//   * -2: fastest compression
	//   * -3: best compression
	PngCompression int `json:"png_compression,omitempty"`

	// MaxConcurrent determines how many request can be served concurrently. Default is 0, which
	// means unlimited
	MaxConcurrent int64 `json:"max_concurrent,omitempty"`
	// contains filtered or unexported fields
}