Skip to content

Networking

Networking functions for making connections and sending data between clients, traversing NATs when possible. See the Steam Networking overview for more information.

This API Is Deprecated

It may be removed in a future Steamworks SDK release but should continue to work. Valve suggest using Networking Sockets or Networking Messages instead.

Only available in the main GodotSteam branches and GodotSteam Server branches

Functions

acceptP2PSessionWithUser

acceptP2PSessionWithUser( uint64_t steam_id_remote )

This allows the game to specify accept an incoming packet. This needs to be called before a real connection is established to a remote host, the game will get a chance to say whether or not the remote user is allowed to talk to them.

When a remote user that you haven't sent a packet to recently, tries to first send you a packet, your game will receive a callback p2p_session_request. This callback contains the Steam ID of the user who wants to send you a packet. In response to this callback, you'll want to see if it's someone you want to talk to (for example, if they're in a lobby with you), and if so, accept the connection; otherwise if you don't want to talk to the user, just ignore the request. If the user continues to send you packets, another p2p_session_request will be posted periodically. If you've called sendP2PPacket on the other user, this implicitly accepts the session request.

Returns: bool

  • true upon success; false only if steam_id_remote is invalid.

Note: This call should only be made in response to a p2p_session_request callback.


Read more in the official Steamworks SDK documentation

allowP2PPacketRelay

allowP2PPacketRelay( bool allow )

Allow or disallow P2P connections to fall back to being relayed through the Steam servers if a direct connection or NAT-traversal cannot be established.

This only applies to connections created after setting this value, or to existing connections that need to automatically reconnect after this value is set.

P2P packet relay is allowed by default.

Returns: bool

  • This function always returns true.

Read more in the official Steamworks SDK documentation

closeP2PChannelWithUser

closeP2PChannelWithUser( uint64_t steam_id_remote, int channel )

Closes a P2P channel when you're done talking to a user on the specific channel.

Once all channels to a user have been closed, the open session to the user will be closed and new data from this user will trigger a new p2p_session_request callback.

Returns: bool

  • true if the channel was successfully closed; otherwise, false if there was no active session or channel with the user.

Read more in the official Steamworks SDK documentation

closeP2PSessionWithUser

closeP2PSessionWithUser( uint64_t steam_id_remote )

This should be called when you're done communicating with a user, as this will free up all of the resources allocated for the connection under-the-hood.

If the remote user tries to send data to you again, a new p2p_session_request callback will be posted.

Returns: bool

  • true if the session was successfully closed; otherwise, false if no connection was open with steam_id_remote.

Read more in the official Steamworks SDK documentation

getP2PSessionState

getP2PSessionState( uint64_t steam_id_remote )

Fills out a dictionary with details about the connection like whether or not there is an active connection; number of bytes queued on the connection; the last error code, if any; whether or not a relay server is being used; and the IP and Port of the remote user, if known.

This should only needed for debugging purposes.

Returns: dictionary

Contains the following keys:

  • connection_active (bool)
  • connecting (bool)
  • session_error (uint8)
  • using_relay (bool)
  • bytes_queued_for_send (int32)
  • packets_queued_for_send (int32)
  • remote_ip (uint32)
  • remote_port (uint16)

Read more in the official Steamworks SDK documentation

getAvailableP2PPacketSize

getAvailableP2PPacketSize( int channel )

Calls IsP2PPacketAvailable under the hood, returns the size of the available packet or zero if there is no such packet.

Returns: uint32_t

readP2PPacket

readP2PPacket( uint32_t packet, int channel )

Reads in a packet that has been sent from another user via SendP2PPacket.

This call is not blocking, and will return false if no data is available.

Before calling this you should have called getAvailableP2PPacketSize / isP2PPacketAvailable.

Returns: dictionary

  • data (PoolByteArray)
  • steam_id_remote (uint64_t)

Read more in the official Steamworks SDK documentation

sendP2PPacket

sendP2PPacket( uint64_t steam_id_remote, array data, int send_type, int channel )

Sends a P2P packet to the specified user.

This is a session-less API which automatically establishes NAT-traversing or Steam relay server connections.

See EP2PSend for descriptions of the different ways of sending packets. The integers passed in GodotSteam are:

  • 0 - send ureliable
  • 1 - send unreliable, no delay
  • 2 - send reliable
  • 3 - send reliable with buffering

The type of data you send is arbitrary, you can use an off the shelf system like Protocol Buffers or Cap'n Proto to encode your packets in an efficient way, or you can create your own messaging system.

Sends a P2P packet to the specified user.

Triggers a p2p_session_request callback.

Returns: bool

True if the packet was successfully sent. Note that this does not mean successfully received, if we can't get through to the user after a timeout of 20 seconds, then an error will be posted via the p2p_session_connect_fail callback.

Note: The first packet send may be delayed as the NAT-traversal code runs.


Read more in the official Steamworks SDK documentation

Signals

These callbacks require you to run Steam.run_callbacks() in your _process() function to receive them.

p2p_session_connect_fail

p2p_session_connect_fail

Called when a user sends a packet and it fails.

Returns:

  • steam_id_remote (uint64_t)
  • session_error (uint8_t)

Read more in the official Steamworks SDK documentation

p2p_session_request

p2p_session_request

Called when a user sends a packet.

Returns:

  • steam_id_remote (uint64_t)

Read more in the official Steamworks SDK documentation

Enums

P2PSend

Enumerator Value
P2P_SEND_UNRELIABLE 0
P2P_SEND_UNRELIABLE_NO_DELAY 1
P2P_SEND_RELIABLE 2
P2P_SEND_RELIABLE_WITH_BUFFERING 3

P2PSessionError

Enumerator Value
P2P_SESSION_ERROR_NONE 0
P2P_SESSION_ERROR_NOT_RUNNING_APP 1
P2P_SESSION_ERROR_NO_RIGHTS_TO_APP 2
P2P_SESSION_ERROR_DESTINATION_NOT_LOGGED_ON 3
P2P_SESSION_ERROR_TIMEOUT 4
P2P_SESSION_ERROR_MAX 5

SNetSocketConnectionType

Enumerator Value
NET_SOCKET_CONNECTION_TYPE_NOT_CONNECTED 0
NET_SOCKET_CONNECTION_TYPE_UDP 1
NET_SOCKET_CONNECTION_TYPE_UDP_RELAY 2

SNetSocketState

Enumerator Value
NET_SOCKET_STATE_INVALID 0
NET_SOCKET_STATE_CONNECTED 1
NET_SOCKET_STATE_INITIATED 10
NET_SOCKET_STATE_LOCAL_CANDIDATE_FOUND 11
NET_SOCKET_STATE_RECEIVED_REMOTE_CANDIDATES 12
NET_SOCKET_STATE_CHALLENGE_HANDSHAKE 15
NET_SOCKET_STATE_DISCONNECTING 21
NET_SOCKET_STATE_LOCAL_DISCONNECT 22
NET_SOCKET_STATE_TIMEOUT_DURING_CONNECT 23
NET_SOCKET_STATE_REMOTE_END_DISCONNECTED 24
NET_SOCKET_STATE_BROKEN 25