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Fabian Vogelsteller edited this page Apr 13, 2015 · 90 revisions

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

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

$ geth -logfile /dev/null console

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

Caveat

The go-ethereum CLI uses the Otto JS VM (forked from https://github.com/robertkrimen/otto) 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

The admin exposes the methods to administrate the node.

admin.nodeInfo
admin.nodeInfo()

Returns information on the node.

admin.nodeInfo()
// {...}
> 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.

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

Returns an array of objects with information about connected peers.

admin.peers()
// [{...},{...}]
> 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)

Starts the HTTP server for the JSON-RPC.

Returns true on success, otherwise false.

admin.startRPC("127.0.0.1", 8545)
// true
admin.stopRPC
admin.stopRPC() [not implemented]

Stops the HTTP server for the JSON-RPC.

Returns true on success, otherwise false.

admin.stopRpc()
// true
admin.miner.start
admin.miner.start(threadNumber)

Starts mining on with the given threadNumber of parallel threads.

Returns true on success, otherwise false.

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

admin.miner.start(4)
// true
admin.miner.stop
admin.miner.stop()

Stops all miners.

Returns true on success, otherwise false.

admin.miner.stop()
// true
admin.miner.hashrate
admin.miner.hashrate()

Returns the current hash rate

admin.miner.setExtra
admin.miner.setExtra("extra data")

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

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.

admin.unlock('0x833b8ed5a2957e5b050ba6539efa66cb67165eec', '1234', 1000 * 60 * 10) // unlock for 10 mins
// true
> 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.

admin.newAccount('1234')
// true
> admin.newAccount()
The new account will be encrypted with a passphrase.
Please enter a passphrase now.
Passphrase:
Repeat Passphrase:
'cf68505ae04bb425eb431eceb629c351bd9a4eee'
>
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.

admin.dumpBlock(29)
// {...}
> admin.dumpBlock()
{ Root: 'e26e11f5252fca8b61d5979c0dea584c22d0e1b3bf687c915276c90c04bdb4bb', Accounts: { 2091fc869cbf49e84e72365bfbaee012f7f0c3ad368ef8c56c167ba75538c1ad: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 5b70e80538acdabd6137353b0f9d8d149f4dba91e8be2e7946e409bfdbe685b9: { Balance: '1', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 9bc17373cefddb760ffc916a98ea7152ceb68a400a74fb36e770b695e16e48b0: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, a28629e41841cc5e702899227a10d8fd7debed9ce87f47a95dcc3bedd9a8a4ef: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, cc7fbca600b4bbd1d889076147f61721f0f04cef8b3f1a6ee8097f454543ce55: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, d52688a8f926c816ca1e079067caba944f158e764817b83fc43594370ca9cf62: { Balance: '1', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, e044041bfd3b93fab85f2a1f96c7993754ae741bfe6fee5992f8b23dd181992c: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 1468288056310c82aa4c01a7e12a10f8111a0560e72b700555479031b86c357d: { Balance: '1', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 70009f4500e4fc823b89deed6bb8bfb9b4d3edcffb92a431d65d6e3b920943d7: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 8782e9da2bab05079eceaaa3551f40e16fb8f0c47476b00498a13b25e1de8dd6: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, a876da518a393dbd067dc72abfa08d475ed6447fca96d92ec3f9e7eba503ca61: { Balance: '1', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, fb147bae72727a9e8b7e9fc8c22e690345179367915f7d6c57c43e4c863ae48b: { Balance: '1606938044258990275541962092341162602522202993782792835301376', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } }, 3eb1ce4f84b7004d8c653aa4f5f7be9b54a240c293fbdd2553d1da13ceacf687: { Balance: '42000000000000000000', Nonce: 0, Root: '56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421', CodeHash: 'c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470', Storage: {  } } } }
>
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.

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.

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);
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