VERSION 2.0 will not work with a version 1 Lamden network. Use the previuous version to v2 for an old Lamden network.

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

Install App

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

Run

npm run start

Run api doc server

npm run docs

Run Service with docker

Install docker

curl -fsSL https://get.docker.com | bash -s docker

Then install docker-compose, you can get the latest release at here

sudo curl -L "https://github.com/docker/compose/releases/download/v2.2.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

Clone this project

git clone https://github.com/Lamden/lamden_block_service.git
cd lamden_block_service

Build project

docker-compose build # build docker image

Run the server(not build)

docker-compose up -d

Stop the server

docker-compose stop

start/restart the server

docker-compose up --detach --build

Check Logs

Follow log output

docker-compose logs -f

Number of lines to show from the end of the logs for each container

docker-compose logs -f --tail N

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
GENESIS_BLOCK_URL (optional): a genesis block url if different than the default Lamden Testnet or Lamden Mainnet genesis blocks

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

Api Rate Limit

you can limit the number of api calls for each ip. This feature is turned off by default.

RATE_LIMIT_ENABLE 0: Enable:1 Disable:0
RATE_LIMIT_PERIOD 600000: Time frame for which requests are checked, defaults units is ms
RATE_LIMIT_NUM 10: number of api calls

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.

Lamden / lamden_block_service