This guide goes into details on how to compile and deploy Blockscout instance to work with Polygon-Edge. Blockscout has its own documentation, but this guide focuses on simple but detailed step-by-step instructions on how to setup Blockscout instance.
- Operating System: Ubuntu Server 20.04 LTS download link with sudo permissions
- Server Hardware: 2CPU / 4GB RAM / 50GB HDD (LVM)
- Database Server: Dedicated server with 2 CPU / 4GB RAM / 30GB SSD / PostresSQL 13.4
The requirement for following this guide is to have a database server ready, database and db user configured. This guide will not go into details on how to deploy and configure PosgreSQL server. There are plenty of guides on now to do this, for example DigitalOcean Guide
This guide is meant only to help you to get Blockscout up and running on a single instance which is not ideal production setup.
For production, you'll probably want to introduce reverse proxy, load balancer, scalability options, etc. into the architecture.
Part 1 - install dependancies
Before we start we need to make sure we have all the binaries installed that the blockscout is dependent on.
Update & upgrade system
sudo apt update && sudo apt -y upgrade
Install erlang and its dependancies from default packages
sudo apt -y install erlang
Add erlang repos
# go to your home dir
# download deb
# download key
# install repo
sudo dpkg -i erlang-solutions_2.0_all.deb
# install key
sudo apt-key add erlang_solutions.asc
# remove deb
# remove key
Add NodeJS repo
sudo curl -sL https://deb.nodesource.com/setup_14.x | sudo -E bash -
sudo curl https://sh.rustup.rs -sSf | sh -s -- -y
Install specific versions of Erlang and Elixir
sudo apt -y install esl-erlang=1:24.* elixir=1.12.*
sudo apt -y install nodejs
sudo apt -y install cargo
Install other dependancies
sudo apt -y install automake libtool inotify-tools gcc libgmp-dev make g++ git
Optionaly install postgresql client to check your db connection
sudo apt -y postgresql-client
Part 2 - set environment variables
We need to set the environment variables, before we begin with Blockscout compilation. In this guide we'll set only the basic minimum to get it working. Full list of variables that can be set you can find here
Set env vars
# example: ETHEREUM_JSONRPC_HTTP_URL=https://rpc.poa.psdk.io:8545
export ETHEREUM_JSONRPC_HTTP_URL=<your polygon-edge json-rpc endpoint>
# example: ETHEREUM_JSONRPC_TRACE_URL=https://rpc.poa.psdk.io:8545
export ETHEREUM_JSONRPC_TRACE_URL=<your polygon-edge json-rpc endpoint>
# example: ETHEREUM_JSONRPC_WS_URL=wss://rpc.poa.psdk.io:8545/ws
export ETHEREUM_JSONRPC_WS_URL=<your polygon-edge websocket endpoint>
# used for automaticaly restarting the service if it crashes
export HEART_COMMAND="systemctl start explorer.service"
# postgresql connection example: DATABASE_URL=postgresql://blockscout:[email protected]:5432/blockscout
# secret key base as per docs https://docs.blockscout.com/for-developers/manual-deployment ( Step 4 )
# we set these env vars to test the db connection
Now test your DB connection with provided parameters. Since you've provided PG env vars, you should be able to connect to the database only by running:
If the database is configured correctly, you should see a psql prompt:
psql (12.9 (Ubuntu 12.9-0ubuntu0.20.04.1))
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, bits: 256, compression: off)
Type "help" for help.
Otherwise you might see an error like this:
psql: error: FATAL: password authentication failed for user "blockscout"
FATAL: password authentication failed for user "blockscout"
If this is the case these docs might help you.
Make sure you've sorted out all db connection issues before proceeding to the next part. You'll need to provide superuser privileges to blockscout user.
[email protected]:~$ createuser --interactive
Enter name of role to add: blockscout
Shall the new role be a superuser? (y/n) y
Part 3 - clone and compile Blockscout
Now we finaly get to start the Blockscout installation.
Clone Blockscout repo
git clone https://github.com/poanetwork/blockscout.git
Cd into clone directory and start compiling
mix local.hex --force
mix do deps.get, local.rebar --force, deps.compile, compile
This part will fail if you didn't setup your DB connection properly, you didn't provide or you've defined wrong parameters at DATABASE_URL environment variable. The database user needs to have superuser privileges.
mix do ecto.create, ecto.migrate
Install npm dependancies and compile frontend assets
You need to change directory to the folder which contains frontend assets.
sudo npm install
sudo node_modules/webpack/bin/webpack.js --mode production
Compilation of these assets can take a few minutes, and it will display no output.
It can look like the process is stuck, but just be patient.
When compile process is finished, it should output something like:
webpack 5.69.1 compiled with 3 warnings in 104942 ms
Build static assets
For this step you need to return to the root of your Blockscout clone folder.
sudo mix phx.digest
Generate self-signed certificates
mix phx.gen.cert blockscout blockscout.local
Part 4 - create and run Blockscout service
In this part we need to setup a system service as we want Blockscout to run in the backround and persist after system reboot.
Create service file
sudo touch /etc/systemd/system/explorer.service
Edit service file
Use your favorite linux text editor to edit this file and configure the service.
sudo vi /etc/systemd/system/explorer.service
The contents of the explorer.service file should look like this:
Enable starting service on system boot
sudo systemctl daemon-reload
sudo systemctl enable explorer.service
Move your Blockscout clone folder to system wide location
Blockscout service needs to have access to the folder you've cloned from Blockscout repo and compiled all the assets.
sudo mv ~/blockscout /usr/local
Create env vars file which will be used by Blockscout service
Use the same environment variables as you've set in Part 2.
sudo touch /usr/local/blockscout/env_vars.env
# use your favorite text editor
sudo vi /usr/local/blockscout/env_vars.env
# env_vars.env file should hold these values ( adjusted for your environment )
HEART_COMMAND="systemctl start explorer.service"
Save the file and exit.
Finaly start Blockscout service
sudo systemctl start explorer.service
Part 5 - test out the functionality of your Blockscout instance
Now all thats left to do is to check if Blockscout service is running. Check service status with:
sudo systemctl status explorer.service
To check service output:
sudo journalctl -u explorer.service
You can check if there are some new listening ports:
# if netstat is not installed
sudo apt install net-tools
sudo netstat -tulpn
You should get a list of listening ports and on the list there should be something like this:
tcp 0 0 0.0.0.0:5432 0.0.0.0:* LISTEN 28142/postgres
tcp 0 0 0.0.0.0:4000 0.0.0.0:* LISTEN 42148/beam.smp
tcp 0 0 0.0.0.0:4001 0.0.0.0:* LISTEN 42148/beam.smp
Blockscout web service runs by default on ports
If everythig is ok, you should be able to access the Blockscout web portal with
We've just deployed a single Blockscout instance, which works fine, but for production you should consider placing this instance behind a reverse proxy like Nginx. You sould also think about database and instance scalability, depending on your use case.
You should definitely checkout the official Blockscout documentation as there a lot of customisation options.