cache

type EntryKind int

type Error struct {
	// Corresponds to a http.Status* code
	Code int
	// A human-readable string describing the error
	Text string
}

type Logger interface {
	Printf(format string, v ...interface{})
}

type Proxy interface {
	// Put should make a reasonable effort to proxy this data to the backend.
	// This is allowed to fail silently (eg when under heavy load).
	Put(kind EntryKind, hash string, size int64, rdr io.Reader)

	// Get should return the cache item identified by `hash`, or an error
	// if something went wrong. If the item was not found, the io.ReadCloser
	// will be nil.
	Get(kind EntryKind, hash string) (io.ReadCloser, int64, error)

	// Contains returns whether or not the cache item exists on the
	// remote end, and the size if it exists (and -1 if the size is
	// unknown).
	Contains(kind EntryKind, hash string) (bool, int64)
}