#How To Setup A Node With Docker?

#Introduction

Docker is the de facto industry standard for packaging applications into a container. By doing so, all dependencies, such as the language run-times, operating system, and libraries are combined with the product.

#Prerequisites

Prerequisites to be installed:

• Docker Engine
• Docker Compose

#Supported Cloud Providers

Different cloud providers offer specific products to host your Docker containers, such as:

• Google App Engine
• AWS Elastic Beanstalk
• Azure
• Digital Ocean

Orchestrators with Docker as a first class citizen:

• Kubernetes
• Nomad
• Mesos

#Production Setup

#Get The Needed Docker Files

The code sample below downloads the needed files from our official GitHub Core repository .

NETWORK=devnet
mkdir ~/$NETWORK
cd ~/$NETWORK
curl -sOJ https://raw.githubusercontent.com/ArkEcosystem/core/master/docker/production/$NETWORK/docker-compose.yml
curl -sOJ https://raw.githubusercontent.com/ArkEcosystem/core/master/docker/production/$NETWORK/$NETWORK.env

#Running a Relay Node

cd ~/$NETWORK     # (NETWORK = devnet || mainnet)
docker-compose up -d

This will run two separate containers. One for Core itself and another one for PostgreSQL.

#How To Run a Relay and a Forger Node

#Prerequisites to be installed

• OpenSSL

Two additional steps are needed to be able to run a forger:

Step 1: MODE has to be set to forger (MODE=forger) in your $NETWORK.env file.

cd ~/$NETWORK
sed -i 's/^MODE=relay/MODE=forger/g $NETWORK.env

Step 2. Configure your delegate secret and password. Just use the additional script enc.sh.

You will be asked to enter your delegate secret, followed by entering your password twice. Script will create a new folder named enc, containing set of encrypted public and private keys.

#Now let’s run the forger

This will fire up two separate containers. One for Core itself and another one for PostgreSQL.

#Custom Settings

In case you want to use a remote PostgreSQL server simply adjust variable CORE_DB_HOST in your $NETWORK.env and run only Core container:

cd ~/$NETWORK
docker-compose up -d core

#FAQ

#How Do I Start With Empty DB?

Just execute the following code:

cd ~/$NETWORK
docker-compose down -v
docker-compose up -d

#Where Are the Config Files and Logs Located?

ARK Core container mounts by default the following local paths as volumes:

~/.config/ark-core
~/.local/share/ark-core
~/.local/state/ark-core

Having that said, your config files are locally accessible under:

~/.config/ark-core/$NETWORK/

Pool database as well as db snapshots are locally accessible under:

~/.local/share/ark-core/$NETWORK/

Log files are locally accessible under:

~/.local/state/ark-core/$NETWORK/

Alternative way of following the logs would be, by using the command:

docker logs --tail 50 core-$NETWORK -f

#How Do I Start Everything from Scratch?

Just use the purge_all.sh script.

#How To Build Your Own ARK Core Docker Image

This requires cloning ARK Core Github repository .

cd ~/
git clone https://github.com/ArkEcosystem/core

Custom Docker image builds of ARK Core are possible by using the file docker-compose-build.yml. Make your own modifications of ARK Core source code and run your custom container by executing:

cd ~/core/docker/production/$NETWORK     # (NETWORK = devnet || mainnet)
docker-compose -f docker-compose-build.yml up -d

This will build your ARK Core Docker image and run two separate containers. One for Core itself and another one for PostgreSQL.

#How To Update Core Version Within Docker Image

#Option 1: Docker Live Updates Are Now Possible With CLI

As a preliminary step, installation of development tools is necessary (only needed once, when doing initial update):

docker exec -it core-$NETWORK sudo apk add make gcc g++ git python

We are all set! Run the update and follow instructions:

docker exec -it core-$NETWORK ark update

#Option 2: Update is also possible by destroying and running Core container from scratch, so it downloads the latest image

cd ~/$NETWORK
docker stop core-$NETWORK
docker rm core-$NETWORK
docker rmi $(docker images -q)
docker-compose up -d core

#Development

#Generate the Configurations

ARK Core includes several Dockerfile and docker-compose.yml templates to ease the development. They can be used to generate different configurations, depending on the network and token.

For instance, you could use this command from the root core folder:

1yarn docker ark

This command creates a new directory (docker) that contains 1 folder per network.

#Containerize the Persistent Store

#Run a PostgreSQL container while using NodeJS from your local environment.

This configuration is well suited when you are not developing ARK Core, but instead working with the API. By tearing down the PostgreSQL container, you reset the Nodes blockchain.

Clone ARK Core Github repository :

cd ~/
git clone https://github.com/ArkEcosystem/core

cd ~/core/docker/development/$NETWORK     # (NETWORK = testnet || devnet)
docker-compose up

To run the containers in the background :

In case you need to start with a clean Database:

1docker-compose down -v
2docker-compose up -d

#Serve ARK Core as a Collection of Containers

#Run a PostgreSQL container, build and run ARK-Core using a mounted volume.

When a container is built, all files are copied inside the container. It cannot interact with the host’s filesystem unless a directory is specifically mounted during container start. This configuration works well when developing ARK Core itself, as you do not need to rebuild the container to test your changes.

cd ~/core/docker/development/$NETWORK      # (NETWORK = testnet || devnet)
docker-compose up -d

Enter your ark-core container and use NodeJS in a Docker container (Linux environment) with the following command:

1docker exec -it ark-$NETWORK-core bash

Need to start everything from scratch and make sure there are no remaining cached containers, images or volumes left? Just use the purge_all.sh script.