demux-js-eos-state-history

Demux Action Reader implementation to read block and action data from EOS State History.

Installation

# Using yarn
yarn add demux-eos-state-history

# Using npm
npm install demux-eos-state-history --save

Setup

To use the StateHistoryWsActionReader, you must first make sure that your environment is properly configured. To set up a proper environment, make sure the following are true:

• The node you are connecting to:
  • Has the eosio::state_history_plugin enabled
  • Is connected to the node(s) producing blocks via the p2p-peer-address configuration
  • Has the read-mode configuration set to read-only
  • Has the trace-history configuration enabled

Inline and Deferred Actions

Unlike the NodeosActionReader from demux-js-eos, inline and deferred actions are able to be captured and passed on to the Action Handler.

Example

const { BaseActionWatcher } = require("demux")
const { StateHistoryWsActionReader } = require("demux-eos-state-history")

// See supported Action Handlers here: https://github.com/EOSIO/demux-js#class-implementations
const actionHandler = ...

const actionReader = new StateHistoryWsActionReader({
  startAtBlock: 1234,                         // startAtBlock: the first block relevant to our application
  onlyIrreversible: false,                    // onlyIrreversible: whether or not to only process irreversible blocks
  nodeosRPCEndpoint: "http://localhost:8888", // Nodeos RPC URL. This is used to fetch smart contracts ABIs
  nodeosWSEndpoint: "ws://localhost:8080"     // Nodeos Websocket endpoint. It's configured using the state-history-endpoint configuration
})

const actionWatcher = new BaseActionWatcher(actionReader, actionHander, 500)

// This must be done before calling watch
actionReader.initialize().then(() =>
  actionWatcher.watch()
)

License

MIT