Perform the following steps to install, configure, and run
an instance of hedera-json-rpc-relay on your localhost.
(1)
Clone hedera-json-rpc-relay from with git:
git clone git@github.com:hashgraph/hedera-json-rpc-relay.git(2)
cd into the hedera-json-rpc-relay, and in there create a .env file,
with the following contents:
HEDERA_NETWORK=testnet
OPERATOR_ID_MAIN=YOUR_OPERATOR_ID
OPERATOR_KEY_MAIN=YOUR_OPERATOR_KEY
CHAIN_ID=0x128
MIRROR_NODE_URL=https://testnet.mirrornode.hedera.com/(3)
Replace YOUR_OPERATOR_ID with a Hedera-native address (S.R.N format),
and YOUR_OPERATOR_KEY with the ED22519 private key corresponding to this address
(DER encoded private key).
You can obtain these from the Hedera Portal.
(4) Install dependencies.
npm install(5) Run the server.
npm run start(6)
You can now use http://localhost:7546 as your JSON-RPC endpoint URL.
Note that interacting with this is interacting with the Hedera Testnet,
as under the hood, the server that you are running on localhost
is communicating with, and translating the messages from/to JSON-RPC:
- Hedera Mirror Nodes over REST APIs
- Hedera Consensus Nodes over gRPC
In the rpc-requests.sh file in this directory,
there will be several curl commands to perform JSON-RPC requests to
the RPC relay server that you have running on localhost.
(1)
RPC for net_version.
Should respond with a result of 0x128,
which is 296 in decimcal, and equal to the chain ID of Hedera Testnet.
This verifies that our server has connected to the intended network.
(2)
RPC for eth_blockNumber
This gets the latest block number on the network.
The result property in the reponse is in hexadecimal,
and we pipe it through tr and bc to convert to its equivalent decimal value.
(3)
RPC for eth_getBalance
This gets the balance of the account,
whose address is specified in ADDRESS_EVM -
update this value to that of your own wallet.
The result property in the reponse is in hexadecimal,
and again, we pipe it through tr and bc to convert to its equivalent decimal value.
Note that unlike within Solidity, in the RPC layer, the smallest unit is Weibars (10^-18 HBAR), and not Tinybars (10^-8 HBAR).