Steemex

Elixir websockets client for Steem JSONRPC interface. Steemex is a supervised application, so don't forget to add it to applications in mix.exs

Installation

1. Add steemex to your list of dependencies in mix.exs:

```elixir
def deps do
  [
    {:steemex, ">= 0.0.0"}
  ]
end
```

1. Add 'steemex' to applications in mix.exs: elixir def application do [applications: [:logger, :steemex]] end

Configuration

First, configure a websockets url for the steemd instance, for example, a public node wss://steemd.steemit.com/ to the config.

config :steemex,
  url: System.get_env("STEEM_URL"),

Steemex module includes structs for all operations types. Streamer module parses each operation and converts it to a corresponding struct.

JSONRPC API

The main module function is Steemex.call. It will block the calling process and return a success tuple with a "result" data from the JSONRPC call response. JSONRPC call ids are handled automatically.

Documentation

All database api functions have docs, typespecs and example API responses. Most example responses are from the Golos blockchain, their shape is identical to Steem counterparts.

GenStage

ExGolos uses GenStage, a new specification for handling and exchanging events among Elixir/Erlang processes.

On module app startup two GenStage processes are started and registered:

• Golos.Stage.Blocks.Producer which, perhaps unsurprisingly, is a new blocks producer
• Golos.Stage.Ops.ProducerConsumer consumes blocks and produces operations

An example of GenStage consumer to handle stream of new operations

defmodule Steemex.Stage.Ops.ExampleConsumer do
  use GenStage
  require Logger

  def start_link(args, options \\ []) do
    GenStage.start_link(__MODULE__, args, options)
  end

  def init(state) do
    {:consumer, state, subscribe_to: state.subscribe_to}
  end

  def handle_events(events, _from, state) do
    for op <- events do
      Logger.info """
      New operation:
      #{inspect op}
      """
    end
    {:noreply, [], state}
  end

end

Roadmap

Steemex is under active development.

• Investigate using GenStage
• Add more utility functions
• Add more types and structs
• Add transaction broadcasting