Korva - a DLNA push service

Korva is a small, DBus-activateable daemon which does the device discovery and the push work.

Repository

Interfaces

org.jensge.Korva.Controller1

org.jensge.Korva.Controller1

The Controller1 interface has four methods:

aa{sv} org.jensge.Korva.Controller1.GetDevices ()
a{sv}  org.jensge.Korva.Controller1.GetDeviceInfo (IN s uid)
s      org.jensge.Korva.Controller1.Push (IN a{sv} source, IN s uid)
b      org.jensge.Korva.Controller1.Unshare (IN s tag)

Methods

org.jensge.Korva.Controller1.GetDevices

Returns a list of dictionaries containing information about the current known devices. The mandatory properties are:

Type	Key	Description
s	UID	Unique (per protocol) device identifier. For UPnP this is the UDN of the device
s	DisplayName	Name of the device for display in an UI. Guaranteed to be UTF-8
s	IconURI	Local URI to an icon for the device. May be provided by the device or a generic icon
s	Protocol	Currently fixed to "UPnP". Might be "AirPlay" or different in the future
u	Type	Whether the device is a server or a client. Used for Upload

org.jensge.Korva.Controller1.GetDeviceInfo

Return information about a single device. For description of the parameters and return values see GetDevices.

Type	Parameter	Description
s	uid	A unique identifier of the device as returned by `GetDevices`

org.jensge.Korva.Controller1.Push

Push a media file to a remote device.

Type	Parameter	Description
a{sv}	source	A dictionary with meta-data about the file to be pushed. The only mandatory key is "URI". See MetaData for possible keys and their meaning
s	uid	A unique identifier of the device as returned by `GetDevices`

If the device associated with the UID is a server and it has the proper capabilities (UPnP CreateObject support, proper DLNA OCM flags), Push will try to upload the file to the device.

'Push' returns a tag that can be used with 'Unshare' to explicitly stop sharing of the file. This tag is unique for the combination of device and file.

MetaData

Type	Key	Description	Mandatory
s	URI	(Local) uri of the media file to push to the remote device	✓
t	Size	Size of the media file	✗
s	Title	A title for the media file	✗
s	ContentType	Content type of the file	✗

Errors

org.jensge.Korva.Error.NoSuchDevice
org.jensge.Korva.Error.Timeout
org.jensge.Korva.Error.FileNotFound
org.jensge.Korva.Error.NotCompatible
org.jensge.Korva.Error.InvalidArgs
org.jensge.Korva.Error.NoSuchTransfer
org.jensge.Korva.Error.NotAccessible

Signals

org.jensge.Korva.Controller1.DeviceAvailable(IN a{sv} device)
org.jensge.Korva.Controller1.DeviceUnavailable(IN s UID)

Comments

After our discussion on #gnome-os (-- BastienNocera 2011-12-07 17:57:54):
- Push() should return a more meaningful error message
  - -> Proposed some errors -- JensGeorg 2012-02-24 18:14:00
- An explicit Unshare() should probably be added, as well as unsharing when a new URL is pushed (per-device, obviously), or when the controlling server goes away (Totem crashes, video isn't shared any more)
  - -> How to know that the controlling server went away? -- JensGeorg 2012-02-24 18:14:00
    - -> g_bus_watch_name() on the client's D-Bus name. -> Needs a bit more fine-grained control for one-shot tools like korva-control or the Harmattan sharing plugin
- The code itself should be extensible to allow showing AirPlay devices in the same way
  - -> removed all UPnP"isms" from the D-Bus interface. -- JensGeorg 2012-02-24 18:14:00

dLeyna Renderer

The dLeyna framework offers a component which is similar in spirit to Korva, dLeyna Renderer. The DBus API uses multiple interfaces:

com.intel.dLeynaRenderer.Manager: enumerates the discovered DMRs on the network and notififies applications when they appear/disappear
com.intel.dLeynaRenderer.RendererDevice: export useful info about the remote device itself
org.mpris.MediaPlayer2.Player: is used to control the status of the DMR
com.intel.dLeynaRenderer.PushHost: helps applications to implement the "2 box push" use case, where there's no DMS involved and it's the application itself that exports the media contents

A more complete description of the DBus API can be found at https://github.com/01org/dleyna-renderer/blob/master/doc/server/dbus/API.txt