Coins

Coins is an example app using CQRS and Event Sourcing.

It uses:

• Commanded: Framework to create CQRS/ES appliactions
• Commanded Ecto Projections: Projections on an Ecto DB
• Commanded EventStore Adapter: EventStore adapter for commanded using postgres

Using

Setup the databases with mix setup_db and then run iex -S mix

iex> Coins.mine_coin("me", 1)
{:error, :invalid_nonce}

iex> Coins.mine_coin("me", 190)
:ok

iex> Coins.mine_coin("me", 190)
{:error, :used_nonce}

iex> Coins.mine_coin("me", 443)
:ok

iex> Coins.richest |> Map.take([:account_id, :balance])
%{account_id: "me", balance: 1}

iex> [488, 1442, 1597] |> Enum.map(&(Coin.mine_coin("you" &1)))
[:ok, :ok, :ok]

iex> Coins.richest |> Map.take([:account_id, :balance])
%{account_id: "you", balance: 3}

iex> Coins.send_coins("you", "me", 99999)
{:error, :not_enough_coins}

iex> Coins.send_coins("you", "me", 3)
:ok

iex> Coins.richest |> Map.take([:account_id, :balance])
%{account_id: "me", balance: 5}