Plian
Chinese
搜索
⌃K

JSON RPC API

Pchain JSON RPC API

​JSON is a lightweight data-interchange format. It can represent numbers, strings, ordered sequences of values, and collections of name/value pairs. JSON RPC is a stateless, light-weight remote procedure call (RPC) protocol. Primarily this specification defines several data structures and the rules around their processing. It is transport agnostic in that the concepts can be used within the same process, over sockets, over HTTP, or in many various message passing environments. It uses JSON (RFC 4627) as data format.

JavaScript API

To talk to a pchain node from inside a JavaScript application, use the pweb3 library, which gives a convenient interface for the RPC methods. See the JavaScript API for more.

Java API

To talk to a pchain node from inside a Java application use the pweb3j library.

JSON RPC URL

Default JSON RPC URL
Chain Name
Chain Id
Default Datadir Directory
Main Chain
pchain
Subchain 1
child_0
Your Chain
your_chain_id

How To Open RPC

You can start pchain with flag –rpc
pchain --rpc
After this, if you want to check the main chain’s current block number, the command will look like this:
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' localhost:6969/pchain
Or if you want to check the subchain’s current block number, the command will look like this:
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}' localhost:6969/child_0
You can also send requests by Postman, you will need to start pchain with the flag “–rpc –rpcaddr=0.0.0.0”. Be aware, opening your RPC to remote hosts is very dangerous if you keep your account information on your node.

Reference

Pchain Utility RPC

Chain RPC

Epoch RPC

Delegation RPC

​

Library

web3_clientVersion

Returns the latest software version
Parameters
none
Returns
String - The current client version.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"web3_clientVersion","params":[],"id":67}'
​
// Result
{
"id":67,
"jsonrpc":"2.0",
"result": "Mist/v0.9.3/darwin/go1.4.1"
}

web3_sha3

Returns Keccak-256 (not the standardized SHA3-256) of the given data.
Parameters
  1. 1.
    DATA - the data to convert into a SHA3 hash.
params: [
"0x68656c6c6f20776f726c64"
]
Returns
DATA - The SHA3 result of the given string.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"web3_sha3","params":["0x68656c6c6f20776f726c64"],"id":64}'
​
// Result
{
"id":64,
"jsonrpc": "2.0",
"result": "0x47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad"
}

net_version

Returns the current network id.
Parameters
none
Returns
String - The current network id.
  • "1": Pchain Mainnet
  • "2": Testnet
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"net_version","params":[],"id":67}'
​
// Result
{
"id":67,
"jsonrpc": "2.0",
"result": "3"
}

net_listening

Returns true if client is actively listening for network connections.
Parameters
none
Returns
Boolean - true when listening, otherwise false.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"net_listening","params":[],"id":67}'
​
// Result
{
"id":67,
"jsonrpc":"2.0",
"result":true
}

net_peerCount

Returns number of peers currently connected to the client.
Parameters
none
Returns
QUANTITY - integer of the number of connected peers.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"net_peerCount","params":[],"id":74}'
​
// Result
{
"id":74,
"jsonrpc": "2.0",
"result": "0x2" // 2
}

eth_protocolVersion

Returns the current pchain protocol version.
Parameters
none
Returns
String - The current pchain protocol version.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_protocolVersion","params":[],"id":67}'
​
// Result
{
"id":67,
"jsonrpc": "2.0",
"result": "54"
}

eth_syncing

Returns an object with data about the sync status or false.
Parameters
none
Returns
Object|Boolean, An object with sync status data or FALSE, when not syncing:
  • startingBlock: QUANTITY - The block at which the import started (will only be reset, after the sync reached his head)
  • currentBlock: QUANTITY - The current block, same as eth_blockNumber
  • highestBlock: QUANTITY - The estimated highest block
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_syncing","params":[],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": {
startingBlock: '0x384',
currentBlock: '0x386',
highestBlock: '0x454'
}
}
// Or when not syncing
{
"id":1,
"jsonrpc": "2.0",
"result": false
}

eth_coinbase

Returns the client coinbase address.
Parameters
none
Returns
DATA, 20 bytes - the current coinbase address.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_coinbase","params":[],"id":64}'
​
// Result
{
"id":64,
"jsonrpc": "2.0",
"result": "0xc94770007dda54cF92009BFF0dE90c06F603a09f"
}

eth_mining

Returns true if client is actively mining new blocks.
Parameters
none
Returns
Boolean - returns true of the client is mining, otherwise false.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_mining","params":[],"id":71}'
​
// Result
{
"id":71,
"jsonrpc": "2.0",
"result": true
}

eth_hashrate

Returns the number of hashes per second that the node is mining with.
Parameters
none
Returns
QUANTITY - number of hashes per second.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_hashrate","params":[],"id":71}'
​
// Result
{
"id":71,
"jsonrpc": "2.0",
"result": "0x38a"
}

eth_gasPrice

Returns the current price per gas in wei.
Parameters
none
Returns
QUANTITY - integer of the current gas price in wei.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_gasPrice","params":[],"id":73}'
​
// Result
{
"id":73,
"jsonrpc": "2.0",
"result": "0x09184e72a000" // 10000000000000
}

eth_accounts

Returns a list of addresses owned by client.
Parameters
none
Returns
Array of DATA, 20 Bytes - addresses owned by the client.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_accounts","params":[],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": ["0xc94770007dda54cF92009BFF0dE90c06F603a09f"]
}

eth_blockNumber

Returns the number of most recent block.
Parameters
none
Returns
QUANTITY - integer of the current block number the client is on.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'
​
// Result
{
"id":83,
"jsonrpc": "2.0",
"result": "0xc94" // 1207
}

eth_getBalance

Returns the balance of the account of given address.
Parameters
  1. 1.
    DATA, 20 Bytes - address to check for balance.
  2. 2.
    QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter​
params: [
'0xc94770007dda54cF92009BFF0dE90c06F603a09f',
'latest'
]
Returns
QUANTITY - integer of the current balance in wei.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0xc94770007dda54cF92009BFF0dE90c06F603a09f", "latest"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x0234c8a3397aab58" // 158972490234375000
}

eth_getStorageAt

Returns the value from a storage position at a given address.
Parameters
  1. 1.
    DATA, 20 Bytes - address of the storage.
  2. 2.
    QUANTITY - integer of the position in the storage.
  3. 3.
    QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter​
Returns
DATA - the value at this storage position.
Example
Calculating the correct position depends on the storage to retrieve. Consider the following contract deployed at 0x295a70b2de5e3953354a6a8344e616ed314d7251 by address 0x391694e7e0b0cce554cb130d723a9d27458f9298.
contract Storage {
uint pos0;
mapping(address => uint) pos1;
function Storage() {
pos0 = 1234;
pos1[msg.sender] = 5678;
}
}
Retrieving the value of pos0 is straight forward:
curl -X POST --data '{"jsonrpc":"2.0", "method": "eth_getStorageAt", "params": ["0x295a70b2de5e3953354a6a8344e616ed314d7251", "0x0", "latest"], "id": 1}' localhost:8545
​
{"jsonrpc":"2.0","id":1,"result":"0x00000000000000000000000000000000000000000000000000000000000004d2"}
Retrieving an element of the map is harder. The position of an element in the map is calculated with:
keccack(LeftPad32(key, 0), LeftPad32(map position, 0))
This means to retrieve the storage on pos1["0x391694e7e0b0cce554cb130d723a9d27458f9298"] we need to calculate the position with:
keccak(decodeHex("000000000000000000000000391694e7e0b0cce554cb130d723a9d27458f9298" + "0000000000000000000000000000000000000000000000000000000000000001"))
The geth console which comes with the web3 library can be used to make the calculation:
> var key = "000000000000000000000000391694e7e0b0cce554cb130d723a9d27458f9298" + "0000000000000000000000000000000000000000000000000000000000000001"
undefined
> web3.sha3(key, {"encoding": "hex"})
"0x6661e9d6d8b923d5bbaab1b96e1dd51ff6ea2a93520fdc9eb75d059238b8c5e9"
Now to fetch the storage:
curl -X POST --data '{"jsonrpc":"2.0", "method": "eth_getStorageAt", "params": ["0x295a70b2de5e3953354a6a8344e616ed314d7251", "0x6661e9d6d8b923d5bbaab1b96e1dd51ff6ea2a93520fdc9eb75d059238b8c5e9", "latest"], "id": 1}' localhost:8545
​
{"jsonrpc":"2.0","id":1,"result":"0x000000000000000000000000000000000000000000000000000000000000162e"}

eth_getTransactionCount

Returns the number of transactions sent from an address.
Parameters
  1. 1.
    DATA, 20 Bytes - address.
  2. 2.
    QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter​
params: [
'0xc94770007dda54cF92009BFF0dE90c06F603a09f',
'latest' // state at the latest block
]
Returns
QUANTITY - integer of the number of transactions send from this address.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getTransactionCount","params":["0xc94770007dda54cF92009BFF0dE90c06F603a09f","latest"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x1" // 1
}

eth_getBlockTransactionCountByHash

Returns the number of transactions in a block from a block matching the given block hash.
Parameters
  1. 1.
    DATA, 32 Bytes - hash of a block.
params: [
'0xb903239f8543d04b5dc1ba6579132b143087c68db1b2168786408fcbce568238'
]
Returns
QUANTITY - integer of the number of transactions in this block.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockTransactionCountByHash","params":["0xc94770007dda54cF92009BFF0dE90c06F603a09f"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xc" // 11
}

eth_getBlockTransactionCountByNumber

Returns the number of transactions in a block matching the given block number.
Parameters
  1. 1.
    QUANTITY|TAG - integer of a block number, or the string "earliest", "latest" or "pending", as in the default block parameter.
params: [
'0xe8', // 232
]
Returns
QUANTITY - integer of the number of transactions in this block.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockTransactionCountByNumber","params":["0xe8"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xa" // 10
}

eth_getUncleCountByBlockHash

Returns the number of uncles in a block from a block matching the given block hash.
Parameters
  1. 1.
    DATA, 32 Bytes - hash of a block.
params: [
'0xc94770007dda54cF92009BFF0dE90c06F603a09f'
]
Returns
QUANTITY - integer of the number of uncles in this block.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getUncleCountByBlockHash","params":["0xc94770007dda54cF92009BFF0dE90c06F603a09f"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xc" // 1
}

eth_getUncleCountByBlockNumber

Returns the number of uncles in a block from a block matching the given block number.
Parameters
  1. 1.
    QUANTITY|TAG - integer of a block number, or the string "latest", "earliest" or "pending", see the default block parameter.
params: [
'0xe8', // 232
]
Returns
QUANTITY - integer of the number of uncles in this block.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getUncleCountByBlockNumber","params":["0xe8"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x1" // 1
}

eth_getCode

Returns code at a given address.
Parameters
  1. 1.
    DATA, 20 Bytes - address.
  2. 2.
    QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter.
params: [
'0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b',
'0x2' // 2
]
Returns
DATA - the code from the given address.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getCode","params":["0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b", "0x2"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x600160008035811a818181146012578301005b601b6001356025565b8060005260206000f25b600060078202905091905056"
}

eth_sign

The sign method calculates an pchain specific signature with: sign(keccak256("\x19Ethereum Signed Message:\n" + len(message) + message))).
By adding a prefix to the message makes the calculated signature recognisable as an pchain specific signature. This prevents misuse where a malicious DApp can sign arbitrary data (e.g. transaction) and use the signature to impersonate the victim.
Note the address to sign with must be unlocked.
Parameters
account, message
  1. 1.
    DATA, 20 Bytes - address.
  2. 2.
    DATA, N Bytes - message to sign.
Returns
DATA: Signature
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sign","params":["0x9b2055d370f73ec7d8a03e965129118dc8f5bf83", "0xdeadbeaf"],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xa3f20717a250c2b0b729b7e5becbff67fdaef7e0699da4de7ca5895b02a170a12d887fd3b17bfdce3481f10bea41f45ba9f709d39ce8325427b57afcfc994cee1b"
}
An example how to use solidity ecrecover to verify the signature calculated with eth_sign can be found here. The contract is deployed on the testnet Ropsten and Rinkeby.

eth_sendTransaction

Creates new message call transaction or a contract creation, if the data field contains code.
Parameters
  1. 1.
    Object - The transaction object
  • from: DATA, 20 Bytes - The address the transaction is send from.
  • to: DATA, 20 Bytes - (optional when creating new contract) The address the transaction is directed to.
  • gas: QUANTITY - (optional, default: 90000) Integer of the gas provided for the transaction execution. It will return unused gas.
  • gasPrice: QUANTITY - (optional, default: To-Be-Determined) Integer of the gasPrice used for each paid gas
  • value: QUANTITY - (optional) Integer of the value sent with this transaction
  • data: DATA - The compiled code of a contract OR the hash of the invoked method signature and encoded parameters. For details see Pchain Contract ABI​
  • nonce: QUANTITY - (optional) Integer of a nonce. This allows to overwrite your own pending transactions that use the same nonce.
params: [{
"from": "0xb60e8dd61c5d32be8058bb8eb970870f07233155",
"to": "0xd46e8dd67c5d32be8058bb8eb970870f07244567",
"gas": "0x76c0", // 30400
"gasPrice": "0x9184e72a000", // 10000000000000
"value": "0x9184e72a", // 2441406250
"data": "0xd46e8dd67c5d32be8d46e8dd67c5d32be8058bb8eb970870f072445675058bb8eb970870f072445675"
}]
Returns
DATA, 32 Bytes - the transaction hash, or the zero hash if the transaction is not yet available.
Use eth_getTransactionReceipt to get the contract address, after the transaction was mined, when you created a contract.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sendTransaction","params":[{see above}],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331"
}

eth_sendRawTransaction

Creates new message call transaction or a contract creation for signed transactions.
Parameters
  1. 1.
    DATA, The signed transaction data.
params: ["0xd46e8dd67c5d32be8d46e8dd67c5d32be8058bb8eb970870f072445675058bb8eb970870f072445675"]
Returns
DATA, 32 Bytes - the transaction hash, or the zero hash if the transaction is not yet available.
Use eth_getTransactionReceipt to get the contract address, after the transaction was mined, when you created a contract.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":[{see above}],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331"
}

eth_call

Executes a new message call immediately without creating a transaction on the block chain.
Parameters
  1. 1.
    Object - The transaction call object
  • from: DATA, 20 Bytes - (optional) The address the transaction is sent from.
  • to: DATA, 20 Bytes - The address the transaction is directed to.
  • gas: QUANTITY - (optional) Integer of the gas provided for the transaction execution. eth_call consumes zero gas, but this parameter may be needed by some executions.
  • gasPrice: QUANTITY - (optional) Integer of the gasPrice used for each paid gas
  • value: QUANTITY - (optional) Integer of the value sent with this transaction
  • data: DATA - (optional) Hash of the method signature and encoded parameters. For details see Pchain Contract ABI​
  1. 1.
    QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter​
Returns
DATA - the return value of executed contract.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_call","params":[{see above}],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x"
}

eth_estimateGas

Generates and returns an estimate of how much gas is necessary to allow the transaction to complete. The transaction will not be added to the blockchain. Note that the estimate may be significantly more than the amount of gas actually used by the transaction, for a variety of reasons including EVM mechanics and node performance.
Parameters
See eth_call parameters, expect that all properties are optional. If no gas limit is specified geth uses the block gas limit from the pending block as an upper bound. As a result the returned estimate might not be enough to executed the call/transaction when the amount of gas is higher than the pending block gas limit.
Returns
QUANTITY - the amount of gas used.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_estimateGas","params":[{see above}],"id":1}'
​
// Result
{
"id":1,
"jsonrpc": "2.0",
"result": "0x5208" // 21000
}

eth_getBlockByHash

Returns information about a block by hash.
Parameters
  1. 1.
    DATA, 32 Bytes - Hash of a block.
  2. 2.
    Boolean - If true it returns the full transaction objects, if false only the hashes of the transactions.
params: [
'0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331',
true
]
Returns
Object - A block object, or null when no block was found:
  • number: QUANTITY - the block number. null when its pending block.
  • hash: DATA, 32 Bytes - hash of the block. null when its pending block.
  • parentHash: DATA, 32 Bytes - hash of the parent block.
  • nonce: DATA, 8 Bytes - hash of the generated proof-of-work. null when its pending block.
  • sha3Uncles: DATA, 32 Bytes - SHA3 of the uncles data in the block.
  • logsBloom: DATA, 256 Bytes - the bloom filter for the logs of the block. null when its pending block.
  • transactionsRoot: DATA, 32 Bytes - the root of the transaction trie of the block.
  • stateRoot: DATA, 32 Bytes - the root of the final state trie of the block.
  • receiptsRoot: DATA, 32 Bytes - the root of the receipts trie of the block.
  • miner: DATA, 20 Bytes - the address of the beneficiary to whom the mining rewards were given.
  • difficulty: QUANTITY - integer of the difficulty for this block.
  • totalDifficulty: QUANTITY - integer of the total difficulty of the chain until this block.
  • extraData: DATA - the "extra data" field of this block.
  • size: QUANTITY - integer the size of this block in bytes.
  • gasLimit: QUANTITY - the maximum gas allowed in this block.
  • gasUsed: QUANTITY - the total used gas by all transactions in this block.
  • timestamp: QUANTITY - the unix timestamp for when the block was collated.
  • transactions: Array - Array of transaction objects, or 32 Bytes transaction hashes depending on the last given parameter.
  • uncles: Array - Array of uncle hashes.
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockByHash","params":["0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331", true],"id":1}'
​
// Result
{
"id":1,
"jsonrpc":"2.0",
"result": {
"number": "0x1b4", // 436
"hash": "0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331",
"parentHash": "0x9646252be9520f6e71339a8df9c55e4d7619deeb018d2a3f2d21fc165dde5eb5",
"nonce": "0xe04d296d2460cfb8472af2c5fd05b5a214109c25688d3704aed5484f9a7792f2",
"sha3Uncles": "0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347",
"logsBloom": "0xe670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331",
"transactionsRoot": "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421",
"stateRoot": "0xd5855eb08b3387c0af375e9cdb6acfc05eb8f519e419b874b6ff2ffda7ed1dff",
"miner": "0x4e65fda2159562a496f9f3522f89122a3088497a",
"difficulty": "0x027f07", // 163591
"totalDifficulty": "0x027f07", // 163591
"extraData": "0x0000000000000000000000000000000000000000000000000000000000000000",
"size": "0x027f07", // 163591
"gasLimit": "0x9f759", // 653145
"gasUsed": "0x9f759", // 653145
"timestamp": "0x54e34e8e" // 1424182926
"transactions": [{...},{ ... }]
"uncles": ["0x1606e5...", "0xd5145a9..."]
}
}

eth_getBlockByNumber

Returns information about a block by block number.
Parameters
  1. 1.
    QUANTITY|TAG - integer of a block number, or the string "earliest", "latest" or "pending", as in the default block parameter.
  2. 2.
    Boolean - If true it returns the full transaction objects, if false only the hashes of the transactions.
params: [
'0x1b4', // 436
true
]
Returns
Example
// Request
curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["0x1b4", true],"id":1}'
Result see eth_getBlockByHash​

eth_getTransactionByHash