eth-cli

A collection of CLI tools to help with ethereum learning and development.

REPL

You can start a REPL to interact with the blockchain. By default it connects to http://localhost:8545, but you can use it with any chain.

$ eth repl --mainnet

> eth.getBlockNumber()
6023243

This is just a node REPL with some extra stuff, so whatever you can do in the node REPL you can do it here. The extra stuff includes:

• A web3 instance connected to the chain you selected (and a eth shortcut to web3.eth).
• Promises are resolved automatically and their result is shown.

Load contract

A command similar to eth repl is eth load-contract. It has the same features as the REPL, but it also exposes a Contract variable with an instance of the contract you specified. You do this by passing the address of the contract and a path to its ABI as arguments:

$ eth load-contract path/to/contract.abi 0xd833215cbcc3f914bd1c9ece3ee7bf8b14f841bb
> Contract.methods.add(2, 2).call()
4

The specified ABI can also be a Truffle artifact. In that case, the ABI will be extracted from it.

Other commands

Some other things that can be done with it:

• Generate one (or more) random addresses with eth random-address (or its alias, eth ra):

  $ eth random-address
  0xeBF73aF39E93941C8DfA951B6C78743eBAd7A962
  
  $ eth ra
  0x5D50c5c056e52064EbD91784A6fc6F63Cad0F8A8
  
  $ eth random-address 3
  0xF77b069A8b4d65A5010865621CF1cd74bC799a6b
  0xa3108a1fC9F546C8d8435b20ea3375Ee0F927763
  0xe8257e4891F570D613C6851F9962141575105A87
  

• Get the transaction object for a given transaction hash:

  $ eth --rinkeby tx 0x1622b3d486ff106cd434e749e35a288c3cda35de75884fa4d3b94bcc28d1f100
  {
    "blockHash": "0x885438d0f4c98518597576a9e63e682b825d382197802fa4493634d08901c7d7",
    "blockNumber": 2568527,
    ...
    "v": "0x1b",
    "r": "0xe57f0e9292ab8c25dafebe595b23b084ffdfac3c44f562d65376d2f5470e3947",
    "s": "0x5785816efd0f564b313235a0ab3009ad45e8017db802a6500bd2da977724796a"
  }
  

• Get the hash for a given method signature:

  $ eth method 'transfer(address,uint256)'
  a9059cbb
  

• Get the address where a contract will be deployed, given the address of the account that will create it and its nonce:

  $ eth contract-address 0x90f8bf6a479f320ead074411a4b0e7944ea8c9c1 5
  0xd833215cbcc3f914bd1c9ece3ee7bf8b14f841bb
  

Just run eth to see the full list of commands.

Installation

npm install -g eth-cli