Lamden Block Service

A nodejs application for syncing and serving the Lamden Blockchain to a local app. This application serves as starting point to be able to build an app on Lamden that requires easy access to current state and realtime updates.

Features:

• Easy to install and configure
• Automatically syncs the blockchain state independant of your app
• Automatically stores and updates the current blockchain state and provides endpoint to query any key as well websockets to subscibe to specific current state updates.
• updates can be at the contract, contract.variable or contract.variable:rootKey levels
• updates are provided in a state update object as opposed to a list of state changes ususlly found in the block data
• updates can be had at the specific key level or at the entire transaction level
• endpoints to easily pagenate through the historic changes to state at the contract, contract.variable or contract.variable:rootKey levels for loading history tables in an app

Install instructions

Install Dependancies

1. Mongo DB (latest)
2. Nodejs and NPM

Install App

1. git clone https://github.com/Lamden/lamden_block_service.git
2. npm install

Run

1. npm run start

Run api doc server

npm run docs

Sync Chaindata (Optional)

The first time you run the block service, it will take long time to sync blocks data. In order to avoid waiting for so long, you can use mongodump to export data from another block service to you own block service.

Configure

All configuration is done by an .env file which you need to create in the root of the application folder. Add these variables to the .env to set the following options, defaults are highlighed.
These variables can also be set in any other means you would set an environment varible or pass one into a nodejs app. Restart the app for these setting to take effect.

Lamden configuration items

• NETWORK testnet: Which Lamden network to sync
• MASTERNODE_URL https://testnet-master-1.lamden.io: A URL of a lamden masternode

Mongo DB configuration items

• DBUSER null: database user
• DBPWD null: database password
• AUTHSOURCE admin: auth source if using a user and password
• DBURL 127.0.0.1: database URL
• DBPORT 27017: database port
• DBNAME ${NETWORK}-blockservice: the name of the database. Default is too add -blockservice to the value of the NETWORK variable which defaults to testnet

Runtime options

• DEBUG_ON false: outputs some logs while grabbing blocks

Server options

• BLOCKSERVICE_PORT 3535: The port used for the webserver and websockets
• BLOCKSERVICE_HOST localhost: Api bind host

Misc options

• APIDOC_PORT 8999: Api document port.
• SCRIPT_SOCKET_CONN http://localhost:3232: Estimation script socket server connection.
• LOG_LEVEL info: Log level.
  • 'info' - Displays all messages from all loggers.
  • 'timer' - Displays messages only from the time, timeEnd, debug, warn, error & fatal loggers.
  • 'debug' - Displays messages only from the debug, warn, error & fatal loggers.
  • 'warn' - Displays messages only from the warn, error & fatal loggers.
  • 'error' - Displays messages only from the error & fatal loggers.