ghuc-private

Quickly setup a local, private Happyuc blockchain.

Features:

• Programmatic as well as command-line interface
• Automatically enables IPC and RPC/CORS access
• Override all options passed to the ghuc executable.
• Override genesis block attributes including mining difficulty.
• Execute console commands against the running ghuc instance.
• Logging capture
• Auto-mine (optional)
• Works with Mist wallet

## Requirements:

• Node.js v4 or above (you can install it using nvm)
• Ghuc

Installation

I recommend installing ghuc-private as a global module so that the CLI becomes available in your PATH:

$ npm install -g ghuc-private

Usage

via command-line

Quickstart

$ ghuc-private

You should see something like:

ghuc is now running (pid: 2428).

Hucerbase:  8864324ac84c3b6c507591dfabeffdc1ad02e09b
Data folder:  /var/folders/br6x6mlx113235/T/tmp-242211yX

To attach:  ghuc attach ipc:///var/folders/br6x6mlx113235/T/tmp-242211yX/ghuc.ipc

Note: ghuc-private runs Ghuc on port 60303 by default with networkid 33333

Default account password is 1234 :)

Run the attach command given to attach a console to this running ghuc instance. By default webu RPC is also enabled.

Once it's running launch the Happyuc/Mist wallet with the --rpc http://localhost:8545 CLI option - it should be able to connect to your ghuc instance.

Options

Usage: ghuc-private [options]

Options:
  --balance       Auto-mine until this initial Hucer balance is achieved (default: 0)
  --autoMine     Auto-mine indefinitely (overrides --balance option)
  --ghucPath      Path to ghuc executable to use instead of default
  --genesisBlock  Genesis block overrides as a JSON string
  -v              Verbose logging
  -h, --help      Show help                                                [boolean]
  --version       Output version.

All other options get passed onto the ghuc executable.

You can also pass options directly to ghuc. For example, you can customize network identity, port, etc:

$ ghuc-private --port 10023 --networkid 54234 --identity testnetwork

By default ghuc-private stores its keystore and blockchain data inside a temporarily generated folder, which gets automatically deleted once it exits. You can override this behaviour by providing a custom location using the datadir option:

$ ghuc-private --datadir /path/to/data/folder

When ghuc-private exits it won't auto-delete this data folder since you manually specified it. This allows you to re-use once created keys and accounts easily.

via API

var ghuc = require('ghuc-private');

var inst = ghuc();

inst.start()
  .then(function() {
    // do some work
  });
  .then(function() {
    // stop it
    return inst.stop();
  });
  .catch(function(err) {
    console.error(err);
  })

Same as for the CLI, you can customize it by passing options during construction:

var ghuc = require('ghuc-private');

var inst = ghuc({
  balance: 10,
  ghucPath: '/path/to/ghuc',
  verbose: true,
  ghucOptions: {
    /*
      These options get passed to the ghuc command-line

      e.g.

      mine: true
      rpc: false,
      identity: 'testnetwork123'
    */
  },
  genesisBlock: {
    /*
      Attribute overrides for the genesis block

      e.g.

      difficulty: '0x400'
    */
  }
});

inst.start().then(...);

You can execute webu commands against the running ghuc instance:

var inst = ghuc();

inst.start()
  .then(() => {
    return inst.consoleExec('webu.version.api');
  })
  .then((version) => {
    console.log(version);
  })
  ...

Mining

To start and stop mining:

var inst = ghuc();

inst.start()
  .then(() => {
    return inst.consoleExec('miner.start()');
  })
  ...
  .then(() => {
    return inst.consoleExec('miner.stop()');
  })
  ...

If you've never mined before then Ghuc will first generate a DAG, which could take a while. Use the -v option to Ghuc's logging.

If your machine is mining too quickly and producing multiple blocks with the same number then you may want to increase the mining difficulty in the genesis block:

var inst = ghuc({
  genesisBlock: {
    difficulty: '0x10000000000'
  }
});

inst.start();
...

You can also do this via the CLI:

$ ghuc-private --genesisBlock '{"difficulty":"0x10000000"}'

NOTE: the --balance option will make ghuc-private automatically mine until the given Hucer balance is achieved.

Logging capture

When using the programmatic API you can capture all output logging by passing a custom logging object:

var inst = ghuc({
  verbose: true,
  logger: {
    debug: function() {...},
    info: function() {...},
    error: function() {...}
  }
});

inst.start();

Development

To run the tests:

$ npm install
$ npm test

Contributions

Contributions are welcome. Please see CONTRIBUTING.md.

License

MIT