Configuring the Application

The application is fed genesis.json the first time it starts up via the InitChain ABCI message. There are three fields that the application cares about:

• chain_id must be consistent on all nodes and distinct from all other blockchains. This is used in the tx signatures to provide replay protection from one chain and another
• validators are the initial set and should be stored if the app wishes to dynamically adjust the validator set
• app_state contains a map of data, to set up the initial blockchain state, such as initial balances and any accounts with special permissions.

App State

If the backend ABCI app is weave-based, such as mycoind or bns, the app_state contains one key for each extension that it wishes to initialize. Each element is an array of an extension-specific format, which is fed into Initialized.FromGenesis from the given extension.

Sample to set the balances of a few accounts:

"app_state": {
  "cash": [
    {
      "address": "849f0f5d8796f30fa95e8057f0ca596049112977",
      "coins": [ "88888888 BNS" ]
    },
    {
      "address": "9729455c431911c8da3f5745a251a6a399ccd6ed",
      "coins": [ "7777777.666666 IOV" ]
    }
  ]
}

This format is application-specific and extremely important to set the initial conditions of a blockchain, as the data is one of the largest distinguishing factors of a chain and a fork.

mycoind init will set up one account with a lot of tokens of one name. For anything more complex, you will want to set this up by hand. Note that you should make sure someone has saved the private keys for all addresses or the tokens will never be usable. Also, for cash, ticker must be 3 or 4 upper-case letters.