The sendcustommsg RPC method allows the user to inject a custom message
into the communication with the peer with the given node_id. This is
intended as a low-level interface to implement custom protocol extensions on
top, not for direct use by end-users.
The message must be a hex encoded well-formed message, including the 2-byte
type prefix, but excluding the length prefix which will be added by the RPC
method. The messages must not use even-numbered types, since these may require
synchronous handling on the receiving side, and can cause the connection to be
dropped. The message types may also not use one of the internally handled
types, since that may cause issues with the internal state tracking of
Core Lightning.
The node specified by node_id must be a peer, i.e., it must have a direct
connection with the node receiving the RPC call, and the connection must be
established. For a method to send arbitrary messages over multiple hops,
including hops that do not understand the custom message, see the
createonion and sendonion RPC methods. Messages can only be injected if
the connection is handled by openingd or channeld. Messages cannot be
injected when the peer is handled by onchaind or closingd since these do
not have a connection, or are synchronous daemons that do not handle
spontaneous messages.
On the reveiving end a plugin may implement the custommsg plugin hook and
get notified about incoming messages.
The
sendcustommsgRPC method allows the user to inject a custom message into the communication with the peer with the givennode_id. This is intended as a low-level interface to implement custom protocol extensions on top, not for direct use by end-users.The message must be a hex encoded well-formed message, including the 2-byte type prefix, but excluding the length prefix which will be added by the RPC method. The messages must not use even-numbered types, since these may require synchronous handling on the receiving side, and can cause the connection to be dropped. The message types may also not use one of the internally handled types, since that may cause issues with the internal state tracking of Core Lightning.
The node specified by
node_idmust be a peer, i.e., it must have a direct connection with the node receiving the RPC call, and the connection must be established. For a method to send arbitrary messages over multiple hops, including hops that do not understand the custom message, see thecreateonionandsendonionRPC methods. Messages can only be injected if the connection is handled byopeningdorchanneld. Messages cannot be injected when the peer is handled byonchaindorclosingdsince these do not have a connection, or are synchronous daemons that do not handle spontaneous messages.On the reveiving end a plugin may implement the
custommsgplugin hook and get notified about incoming messages.