neo-go/docs/rpc.md

RPC

Client

Client is provided as a Go package, so please refer to the relevant godocs page.

Server

The server is written to support as much of the JSON-RPC 2.0 Spec as possible. The server is run as part of the node currently.

Example call

An example would be viewing the version of the node:

$ curl -X POST -d '{"jsonrpc": "2.0", "method": "getversion", "params": [], "id": 1}' http://localhost:20332

which would yield the response:

{
  "jsonrpc" : "2.0",
    "id" : 1,
    "result" : {
      "port" : 20333,
      "useragent" : "/NEO-GO:0.36.0-dev/",
      "nonce" : 9318417
    }
}

Supported methods

Method
calculatenetworkfee
getapplicationlog
getbestblockhash
getblock
getblockcount
getblockhash
getblockheader
getblockheadercount
getcommittee
getconnectioncount
getcontractstate
getnativecontracts
getnep17balances
getnep17transfers
getnextblockvalidators
getpeers
getproof
getrawmempool
getrawtransaction
getstateheight
getstateroot
getstorage
gettransactionheight
getunclaimedgas
getversion
invokecontractverify
invokefunction
invokescript
sendrawtransaction
submitblock
submitoracleresponse
validateaddress
verifyproof

Implementation notices

invokefunction

neo-go's implementation of invokefunction does not return tx field in the answer because that requires signing the transaction with some key in the server which doesn't fit the model of our node-client interactions. Lacking this signature the transaction is almost useless, so there is no point in returning it.

It's possible to use invokefunction not only with contract scripthash, but also with contract name (for native contracts) or contract ID (for all contracts). This feature is not supported by the C# node.

getunclaimedgas

It's possible to call this method for any address with neo-go, unlike with C# node where it only works for addresses from opened wallet.

getcontractstate

It's possible to get non-native contract state by its ID, unlike with C# node where it only works for native contracts.

getstorage

This method doesn't work for the Ledger contract, you can get data via regular getblock and getrawtransaction calls.

getnep17balances

neo-go's implementation of getnep17balances does not perform tracking of NEP17 balances for each account as it is done in the C# node. Instead, neo-go node maintains the list of NEP17-compliant contracts, i.e. those contracts that have NEP-17 declared in the supported standards section of the manifest. Each time getnep17balances is queried, neo-go node asks every NEP17 contract for the account balance by invoking balanceOf method with the corresponding args. Invocation GAS limit is set to be 3 GAS. All non-zero NEP17 balances are included in the RPC call result.

Thus, if NEP17 token contract doesn't have NEP-17 standard declared in the list of supported standards but emits proper NEP17 Transfer notifications, the token balance won't be shown in the list of NEP17 balances returned by the neo-go node (unlike the C# node behavior). However, transfer logs of such token are still available via getnep17transfers RPC call.

The behaviour of the LastUpdatedBlock tracking matches the C# node's one.

Unsupported methods

Methods listed down below are not going to be supported for various reasons and we're not accepting issues related to them.

Method	Reason
closewallet	Doesn't fit neo-go wallet model
dumpprivkey	Shouldn't exist for security reasons, see closewallet comment also
getnewaddress	See closewallet comment, use CLI to do that
getwalletbalance	See closewallet comment, use getnep17balances for that
getwalletunclaimedgas	See closewallet comment, use getunclaimedgas for that
importprivkey	Not applicable to neo-go, see closewallet comment
listaddress	Not applicable to neo-go, see closewallet comment
listplugins	neo-go doesn't have any plugins, so it makes no sense
openwallet	Doesn't fit neo-go wallet model
sendfrom	Not applicable to neo-go, see openwallet comment
sendmany	Not applicable to neo-go, see openwallet comment
sendtoaddress	Not applicable to neo-go, see claimgas comment

Extensions

Some additional extensions are implemented as a part of this RPC server.

getblocksysfee call

This method returns cumulative system fee for all transactions included in a block. It can be removed in future versions, but at the moment you can use it to see how much GAS is burned with particular block (because system fees are burned).

submitnotaryrequest call

This method can be used on P2P Notary enabled networks to submit new notary payloads to be relayed from RPC to P2P.

Limits and paging for getnep17transfers

getnep17transfers RPC call never returns more than 1000 results for one request (within specified time frame). You can pass your own limit via an additional parameter and then use paging to request the next batch of transfers.

Example requesting 10 events for address NbTiM6h8r99kpRtb428XcsUk1TzKed2gTc within 0-1600094189 timestamps:

{ "jsonrpc": "2.0", "id": 5, "method": "getnep17transfers", "params":
["NbTiM6h8r99kpRtb428XcsUk1TzKed2gTc", 0, 1600094189, 10] }

Get the next 10 transfers for the same account within the same time frame:

{ "jsonrpc": "2.0", "id": 5, "method": "getnep17transfers", "params":
["NbTiM6h8r99kpRtb428XcsUk1TzKed2gTc", 0, 1600094189, 10, 1] }

Websocket server

This server accepts websocket connections on ws://$BASE_URL/ws address. You can use it to perform regular RPC calls over websockets (it's supposed to be a little faster than going regular HTTP route) and you can also use it for additional functionality provided only via websockets (like notifications).

Notification subsystem

Notification subsystem consists of two additional RPC methods (subscribe and unsubscribe working only over websocket connection) that allow to subscribe to various blockchain events (with simple event filtering) and receive them on the client as JSON-RPC notifications. More details on that are written in the notifications specification.

Reference

• JSON-RPC 2.0 Specification
• NEO JSON-RPC 2.0 docs