resource

type Content struct {
	// Data holds the resouce content, ready to be read (once).
	Data io.Reader

	// Size is the byte count of the data.
	Size int64

	// Fingerprint holds the checksum of the data.
	Fingerprint charmresource.Fingerprint
}

type Opened struct {
	Resource
	io.ReadCloser
}

type Opener interface {
	// OpenResource returns an opened resource with a reader that will
	// stream the resource content.
	OpenResource(name string) (Opened, error)
}

type Resource struct {
	resource.Resource

	// ID uniquely identifies a resource-application pair within the model.
	// Note that the model ignores pending resources (those with a
	// pending ID) except for in a few clearly pending-related places.
	// ID may be empty if the ID (assigned by the model) is not known.
	ID string

	// PendingID identifies that this resource is pending and
	// distinguishes it from other pending resources with the same model
	// ID (and from the active resource). The active resource for the
	// applications will not have PendingID set.
	PendingID string

	// ApplicationID identifies the application for the resource.
	ApplicationID string

	// Username is the ID of the user that added the revision
	// to the model (whether implicitly or explicitly).
	Username string

	// Timestamp indicates when the resource was added to the model.
	Timestamp time.Time
}

type ServiceResources struct {
	// Resources are the current version of the resource for the application that
	// resource-get will retrieve.
	Resources []Resource

	// CharmStoreResources provides the resource info from the charm
	// store for each of the application's resources. The information from
	// the charm store is current as of the last time the charm store
	// was polled. Each entry here corresponds to the same indexed entry
	// in the Resources field.
	CharmStoreResources []resource.Resource

	// UnitResources reports the currenly-in-use version of resources for each
	// unit.
	UnitResources []UnitResources
}

type Unit interface {
	// Name is the name of the Unit.
	Name() string

	// ApplicationName is the name of the application to which the unit belongs.
	ApplicationName() string

	// CharmURL returns the unit's charm URL.
	CharmURL() (*charm.URL, bool)
}

type UnitResources struct {
	// Tag is the tag of the unit.
	Tag names.UnitTag

	// Resources are the resource versions currently in use by this unit.
	Resources []Resource

	// DownloadProgress indicates the number of bytes of the unit's
	// resources, identified by name, that have been downloaded so far
	// by the uniter. This only applies to resources that are currently
	// being downloaded to the unit. All other resources for the unit
	// will not be found in the map.
	DownloadProgress map[string]int64
}