privTx docs

Author: metachris

README.md

@@ -5,6 +5,8 @@ Fork of [ethrpc](https://github.com/onrik/ethrpc) with additional [Flashbots RPC
 * `FlashbotsCallBundle` ([`eth_callBundle`](https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint/#eth_callbundle))
 * `FlashbotsSendBundle` ([`eth_sendBundle`](https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint/#eth_sendbundle))
 * `FlashbotsGetUserStats` ([`flashbots_getUserStats`](https://docs.flashbots.net/flashbots-auction/searchers/advanced/rpc-endpoint/#flashbots_getuserstats))
+* `FlashbotsSendPrivateTransaction` (`eth_sendPrivateTransaction`)
+* `FlashbotsCancelPrivateTransaction` (`eth_cancelPrivateTransaction`)
 * `FlashbotsSimulateBlock`: simulate a full block
 
 ## Usage

flashbotsrpc.go

@@ -681,7 +681,7 @@ func (rpc *FlashbotsRPC) FlashbotsSimulateBlock(privKey *ecdsa.PrivateKey, block
 	return res, err
 }
 
-// docs todo
+// Sends a rawTx to the Flashbots relay. It will be sent to miners as bundle for 25 blocks, after which the transaction is failed.
 func (rpc *FlashbotsRPC) FlashbotsSendPrivateTransaction(privKey *ecdsa.PrivateKey, param FlashbotsSendPrivateTransactionRequest) (txHash string, err error) {
 	rawMsg, err := rpc.CallWithFlashbotsSignature("eth_sendPrivateTransaction", privKey, param)
 	if err != nil {
@@ -691,10 +691,15 @@ func (rpc *FlashbotsRPC) FlashbotsSendPrivateTransaction(privKey *ecdsa.PrivateK
 	return txHash, err
 }
 
-// docs todo
+// Try to cancel a private transaction at the Flashbots relay. If this call returns true this means the cancel was initiated, but it's not guaranteed
+// that the transaction is actually cancelled, only that it won't be sent to miners anymore. A transaction that was already sent to miners might still
+// be included in the next block.
+//
+// Possible errors: 'tx not found', 'tx was already cancelled', 'tx has already expired'
 func (rpc *FlashbotsRPC) FlashbotsCancelPrivateTransaction(privKey *ecdsa.PrivateKey, param FlashbotsCancelPrivateTransactionRequest) (cancelled bool, err error) {
 	rawMsg, err := rpc.CallWithFlashbotsSignature("eth_cancelPrivateTransaction", privKey, param)
 	if err != nil {
+		// possible todo: return specific errors for the 3 possible relay-internal error cases
 		return false, err
 	}
 	err = json.Unmarshal(rawMsg, &cancelled)