multi: add rpcpolling config options

chainreg/chainregistry.go

@@ -399,21 +399,31 @@ func NewPartialChainControl(cfg *Config) (*PartialChainControl, func(), error) {
 			}
 		}
 
-		// Establish the connection to bitcoind and create the clients
+		bitcoindCfg := &chain.BitcoindConfig{
-		// required for our relevant subsystems.
-		bitcoindConn, err := chain.NewBitcoindConn(&chain.BitcoindConfig{
 			ChainParams:        cfg.ActiveNetParams.Params,
 			Host:               bitcoindHost,
 			User:               bitcoindMode.RPCUser,
 			Pass:               bitcoindMode.RPCPass,
-			ZMQConfig: &chain.ZMQConfig{
+			Dialer:             cfg.Dialer,
+			PrunedModeMaxPeers: bitcoindMode.PrunedNodeMaxPeers,
+		}
+
+		if bitcoindMode.RPCPolling {
+			bitcoindCfg.PollingConfig = &chain.PollingConfig{
+				BlockPollingInterval: bitcoindMode.BlockPollingInterval,
+				TxPollingInterval:    bitcoindMode.TxPollingInterval,
+			}
+		} else {
+			bitcoindCfg.ZMQConfig = &chain.ZMQConfig{
 				ZMQBlockHost:    bitcoindMode.ZMQPubRawBlock,
 				ZMQTxHost:       bitcoindMode.ZMQPubRawTx,
 				ZMQReadDeadline: bitcoindMode.ZMQReadDeadline,
-			},
+			}
-			Dialer:             cfg.Dialer,
+		}
-			PrunedModeMaxPeers: bitcoindMode.PrunedNodeMaxPeers,
+
-		})
+		// Establish the connection to bitcoind and create the clients
+		// required for our relevant subsystems.
+		bitcoindConn, err := chain.NewBitcoindConn(bitcoindCfg)
 		if err != nil {
 			return nil, nil, err
 		}

lncfg/bitcoind.go

@@ -16,4 +16,7 @@ type Bitcoind struct {
 	ZMQReadDeadline      time.Duration `long:"zmqreaddeadline" description:"The read deadline for reading ZMQ messages from both the block and tx subscriptions"`
 	EstimateMode         string        `long:"estimatemode" description:"The fee estimate mode. Must be either ECONOMICAL or CONSERVATIVE."`
 	PrunedNodeMaxPeers   int           `long:"pruned-node-max-peers" description:"The maximum number of peers lnd will choose from the backend node to retrieve pruned blocks from. This only applies to pruned nodes."`
+	RPCPolling           bool          `long:"rpcpolling" description:"Poll the bitcoind RPC interface for block and transaction notifications instead of using the ZMQ interface"`
+	BlockPollingInterval time.Duration `long:"blockpollinginterval" description:"The interval that will be used to poll bitcoind for new blocks. Only used if rpcpolling is true."`
+	TxPollingInterval    time.Duration `long:"txpollinginterval" description:"The interval that will be used to poll bitcoind for new tx. Only used if rpcpolling is true."`
 }

sample-lnd.conf

@@ -606,6 +606,14 @@ bitcoin.node=btcd
 ; bitcoind.zmqpubrawtx=tcp://127.0.0.1:28333
 ; bitcoind.zmqreaddeadline=10s
 
+; Use bitcoind's rpc interface to get block and transaction notifications
+; instead of using the zmq interface. Only the rpcpolling option needs to
+; be set in order to enable this, the rest of the options can be used to
+; change the default values used for this configuration.
+; bitcoind.rpcpolling
+; bitcoind.blockpollinginterval=1m
+; bitcoind.txpollinginterval=30s
+
 ; Fee estimate mode for bitcoind. It must be either "ECONOMICAL" or "CONSERVATIVE".
 ; If unset, the default value is "CONSERVATIVE".
 ; bitcoind.estimatemode=CONSERVATIVE
@@ -814,6 +822,14 @@ litecoin.node=ltcd
 ; litecoind.zmqpubrawtx=tcp://127.0.0.1:28333
 ; litecoind.zmqreaddeadline=10s
 
+; Use litecoind's rpc interface to get block and transaction notifications
+; instead of using the zmq interface. Only the rpcpolling option needs to
+; be set in order to enable this, the rest of the options can be used to
+; change the default values used for this configuration.
+; litecoind.rpcpolling
+; litecoind.blockpollinginterval=1m
+; litecoind.txpollinginterval=30s
+
 ; Fee estimate mode for litecoind. It must be either "ECONOMICAL" or "CONSERVATIVE".
 ; If unset, the default value is "CONSERVATIVE".
 ; litecoind.estimatemode=CONSERVATIVE