geode.rb

# Include this module to implement your own stores.
# You must implement the #initialize, #open and #destroy! methods.
module Geode::Store
  # Connect to a store.
  # @param name [Symbol, String] The name of the store
  # @param connection [Hash, String] Connection parameters passed to the DB client
  def initialize(name, connection = nil)
    @name = name.to_s
  end

  # "Open" the store for reading and/or writing.
  # @yield a block which receives `table` as its sole parameter
  # @yieldparam table [Hash] The store's table. Changes to this Hash will
  # be persisted in the store
  # When in doubt, use this method.
  # @example
  #   "store.open { |table| table[:key] = 5 }"
  # @example
  #   "store.open { |table| table[:key] } #=> 5"
  # @return [Object] The return value of the block
  def open
  end

  # "Destroy" the store, deleting all data.
  # The store can be opened again, recreating it in a blank state.
  def destroy!
  end

  # "Peek" inside the store, returning a copy of its table.
  # Changes to this copy will NOT be persisted in the store.
  # Use this if you simply want to view the store's table.
  # @example
  #   "store.peek.key?(:test) #=> false"
  # @return [Hash] A copy of the store's table
  def peek
    open(&:itself)
  end

  # Retrieve the object at `key` from the store.
  # This is implemented using `#peek` and therefore
  # changes to the object returned by this method will NOT
  # be persisted in the store.
  # Use this if you simply need to fetch a value from the store.
  # @example
  #   "store[:key] #=> 5"
  # @param key [Object] The key to look up
  # @return [Object] The object at `key`
  def [](key)
    peek[key]
  end
end