JavaScript Console

The ethereum CLI executable geth has a JavaScript console, which can be started with the console subcommand:

$ geth console

If you need log information, start with:

$ geth -logfile /tmp/eth.log -loglevel 5 console 2>> /tmp/eth.glog

Otherwise mute your logs, so that it does not pollute your console:

$ geth -logfile /dev/null console 2>> /dev/null

or

$ geth -loglevel 0 console

It's also possible to pass files to the JavaScript intepreter. Load and execute any number of files by giving files as arguments to the js subcommand:

$ geth js script1.js script2.js

If you want to have the console as well as load scripts, use loadScript.

Caveat

The go-ethereum CLI uses the Otto JS VM which has some limitations:

"use strict" will parse, but does nothing.
The regular expression engine (re2/regexp) is not fully compatible with the ECMA5 specification.
missing setTimeout and setInterval. These timing functions are not actually part of the ECMA-262 specification. Typically, they belong to the windows object (in the browser).

Since ethereum.js uses the bignumer.js library (MIT Expat Licence), it is also autoloded.

Console API

Ethereum's Javascript console exposes admin functionality and the full JavaScript API.

admin
- nodeInfo
- suggestPeer
- peers
- startRPC
- stopRPC
- miner
  - start
  - stop
  - hashrate
  - setExtra
- unlock
- newAccount
- debug
- import
- export
loadScript
web3
net
eth
shh
db

admin

The admin exposes the methods to administrate the node.

admin.nodeInfo

admin.nodeInfo()

Returns

information on the node.

Example

> admin.nodeInfo()
{ Name: 'Ethereum(G)/v0.9.0/darwin/go1.4.1', NodeUrl: 'enode://c32e13952965e5f7ebc85b02a2eb54b09d55f553161c6729695ea34482af933d0a4b035efb5600fc5c3ea9306724a8cbd83845bb8caaabe0b599fc444e36db7e@89.42.0.12:30303', NodeID: '0xc32e13952965e5f7ebc85b02a2eb54b09d55f553161c6729695ea34482af933d0a4b035efb5600fc5c3ea9306724a8cbd83845bb8caaabe0b599fc444e36db7e', IP: '89.42.0.12', DiscPort: 30303, TCPPort: 30303, Td: '0', ListenAddr: '[89.42.0.12:30303' }

To connect to a node, use the enode-format nodeUrl as an argument to suggestPeer or with CLI param bootnodes.

admin.suggestPeer

admin.suggestPeer(nodeURL)

Pass a nodeURL to suggest a new peer to the network. The nodeURLneed to be in a enode url format.

You can find out your own enode by using nodeInfo or looking at the logs when the node boots up e.g.:

[P2P Discovery] Listening, enode://6f8a80d14311c39f35f516fa664deaaaa13e85b2f7493f37f6144d86991ec012937307647bd3b9a82abe2974e1407241d54947bbb39763a4cac9f77166ad92a0@54.169.166.226:30303

Note: there is good reason this function is called suggestPeer and not addPeer (as well as reason why removePeer is not available. It is ultimately the p2p server's discretion to connect and disconnect peers depending on number of factors. In normal cases however, when the number of maxpeers is not saturated and your suggested peer is well behaved and compatible, connection may even persist for a long time.

Returns

true on success.

Example

admin.suggestPeer('enode://6f8a80d14311c39f35f516fa664deaaaa13e85b2f7493f37f6144d86991ec012937307647bd3b9a82abe2974e1407241d54947bbb39763a4cac9f77166ad92a0@54.169.166.226:30303')

admin.peers

admin.peers()

Returns

an array of objects with information about connected peers.

Example

> admin.peers()
[ { ID: '0x6cdd090303f394a1cac34ecc9f7cda18127eafa2a3a06de39f6d920b0e583e062a7362097c7c65ee490a758b442acd5c80c6fce4b148c6a391e946b45131365b', Name: 'Ethereum(G)/v0.9.0/linux/go1.4.1', Caps: 'eth/56, shh/2', RemoteAddress: '54.169.166.226:30303', LocalAddress: '10.1.4.216:58888' } { ID: '0x4f06e802d994aaea9b9623308729cf7e4da61090ffb3615bc7124c5abbf46694c4334e304be4314392fafcee46779e506c6e00f2d31371498db35d28adf85f35', Name: 'Mist/v0.9.0/linux/go1.4.2', Caps: 'eth/58, shh/2', RemoteAddress: '37.142.103.9:30303', LocalAddress: '10.1.4.216:62393' } ]

admin.startRPC

 admin.startRPC(ipAddress, portNumber, corsheader)

Starts the HTTP server for the JSON-RPC.

Returns

true on success, otherwise false.

Example

admin.startRPC("127.0.0.1", 8545, )
// true

admin.stopRPC

admin.stopRPC()

Stops the HTTP server for the JSON-RPC.

Returns

true on success, otherwise false.

Example

admin.stopRpc()
// true

admin.miner.start

admin.miner.start(threadNumber)

Starts mining on with the given threadNumber of parallel threads.

Note threadNumber is currently idle until thread safety in ethash is fixed.

Returns

true on success, otherwise false.

Example

admin.miner.start(4)
// true

admin.miner.stop

admin.miner.stop()

Stops all miners.

Returns

true on success, otherwise false.

Example

admin.miner.stop()
// true

admin.miner.hashrate

admin.miner.hashrate()

Returns

String Returns the current hash rate in MH.

admin.miner.setExtra

admin.miner.setExtra("extra data")

Sets the extra data for the block when finding a block. Limited to 1024 bytes.

admin.debug.getBlockRlp

admin.debug.getBlockRlp(hashHexStringOrBlockNumber)

Returns the hexadecimal representation of the RLP encoding of the block. See web3.eth.getBlock for more details on block fields and lookup by number or hash.

Returns

The hex representation of the RLP encoding of the block.

Example

> admin.debug.getBlockRlp(131805)
'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'


#### admin.debug.printBlock

    admin.debug.printBlock(hashHexStringOrBlockNumber)

Prints information about the block such as size, total difficulty, as well as header fields properly formatted.

See [web3.eth.getBlock](https://github.com/ethereum/wiki/wiki/JavaScript-API#web3ethgetblock) for more details on block fields and lookup by number or hash.

##### Returns

`true` on success, otherwise `false`.

#### Example

admin.debug.printBlock(131805) BLOCK(be465b020fdbedc4063756f0912b5a89bbb4735bd1d1df84363e05ade0195cb1): Size: 531.00 B TD: 643485290485 { NoNonce: ee48752c3a0bfe3d85339451a5f3f411c21c8170353e450985e1faab0a9ac4cc Header: [

    ParentHash:         ea4dcb53fe575e23742aa30266722a15429b7ba3d33ba8c87012881d7a77e81e
    UncleHash:          1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347
    Coinbase:           a4d8e9cae4d04b093aac82e6cd355b6b963fb7ff
    Root:               1f892bfd6f8fb2ec69f30c8799e371c24ebc5a9d55558640de1fb7ca8787d26d
    TxSha               56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421
    ReceiptSha:         56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421
    Bloom:              00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
    Difficulty:         12292710
    Number:             131805
    GasLimit:           3141592
    GasUsed:            0
    Time:               1429487725
    Extra:              ΞTHΞЯSPHΞЯΞ
    MixDigest:          4cf6d2c4022dfab72af44e9a58d7ac9f7238ffce31d4da72ed6ec9eda60e1850
    Nonce:              3f9e9ce6a261381c

] Transactions: [] Uncles: [] }


***


#### admin.dumpBlock

    admin.dumpBlock(numberOrHash)

##### Returns

the raw dump of a block referred to by block number or block hash or undefined if the block is not found. If the argument is missing or is -1, the current head block is returned.
see [web3.eth.getBlock](https://github.com/ethereum/wiki/wiki/JavaScript-API#web3ethgetblock) for more details on block fields and lookup by number or hash.

##### Example

```js
> admin.dumpBlock()
>

admin.unlock

admin.unlock(address, password, timeout)

Unlock the account for the time timeout in seconds. If password is undefined, the user is prompted for it.

Returns

true on success, otherwise false.

Example

> admin.unlock("8dbad2d2b85bbb727ee35b31e64f5092ff54a93e")
Please enter a passphrase now.
Passphrase:
true
>

admin.newAccount

admin.newAccount(password)

Creates a new account and encrypts it with password. If no password is given the user is prompted for it.

Returns

true on success, otherwise false.

Example

> admin.newAccount()
The new account will be encrypted with a passphrase.
Please enter a passphrase now.
Passphrase:
Repeat Passphrase:
'cf68505ae04bb425eb431eceb629c351bd9a4eee'
>

2

admin.import

admin.import()

Imports the blockchain from a marshalled binary format. Note that the blockchain is reset (to genesis) before the imported blocks are inserted to the chain.

Returns

true on success, otherwise false.

Example

admin.import('path/to/file')
// true

admin.export

admin.export()

Exports the blockchain to the given file in binary format.

Returns

true on success, otherwise false.

Example

admin.export()
// binary ?

loadScript

 loadScript('/path/to/myfile.js');

Loads a JavaScript file and executes it. Relative paths are interpreted as relative to jspath which is specified as a command line flag, see Command Line Options.

web3

The web3 exposes all methods of the JavaScript API.

net

The net is a shortcut for web3.net.

eth

The eth is a shortcut for web3.eth.

shh

The shh is a shortcut for web3.shh.

db

The db is a shortcut for web3.db.

Examples

Balance

coinbase = eth.coinbase;
eth.getBalance(coinbase).toNumber();
eth.filter('pending').watch(function() {
  print(eth.getBalance(coinbase).toNumber());
});

Contract and transaction

note solidity compilation doesn't work

var source = "" +
  "contract test {\n" +
  " /// @notice Will multiply `a` by 7. \n" +
  " function multiply(uint a) returns(uint d) {\n" +
  " return a * 7;\n" +
  " }\n" +
  "}\n";

var desc = [{
  "name": "multiply(uint256)",
  "type": "function",
  "inputs": [
  {
    "name": "a",
    "type": "uint256"
  }
  ],
    "outputs": [
    {
      "name": "d",
      "type": "uint256"
    }
  ]
}];
var address = eth.sendTransaction({code: eth.solidity(source)});
var contract = eth.contract(address, desc);
var param = 3
contract.sendTransaction().multiply(param);

0xA86d8C2C61D0f3b1C5e30a2830ddeCF133006b81

Main Ethereum Wiki

Frontier Release

JavaScript Console

Caveat

Console API

admin

admin.nodeInfo

Returns

Example

admin.suggestPeer

Returns

Example

admin.peers

Returns

Example

admin.startRPC

Returns

Example

admin.stopRPC

Returns

Example

admin.miner.start

Returns

Example

admin.miner.stop

Returns

Example

admin.miner.hashrate

Returns

admin.miner.setExtra

admin.debug.getBlockRlp

Returns

Example

admin.unlock

Returns

Example

admin.newAccount

Returns

Example

admin.import

Returns

Example

admin.export

Returns

Example

loadScript

web3

net

eth

shh

db

Examples

Balance

Contract and transaction

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