This guide goes into details on how to compile and deploy Blockscout instance to work with Polygon-Edge. Blockscout has its own , but this guide focuses on simple but detailed step-by-step instructions on how to setup Blockscout instance.
Environment
Operating System: Ubuntu Server 20.04 LTS 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
DB Server
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
:::info DISCLAMER 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. :::
Blockscout Deployment Procedure
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
cd ~
# download deb
wget https://packages.erlang-solutions.com/erlang-solutions_2.0_all.deb
# download key
wget https://packages.erlang-solutions.com/ubuntu/erlang_solutions.asc
# install repo
sudo dpkg -i erlang-solutions_2.0_all.deb
# install key
sudo apt-key add erlang_solutions.asc
# remove deb
rm erlang-solutions_2.0_all.deb
# remove key
rm erlang_solutions.asc
Optionaly install postgresql client to check your db connection
sudo apt -y postgresql-client
Part 2 - set environment variables
Set env vars
# example: ETHEREUM_JSONRPC_HTTP_URL=https://rpc-testnet.alveychain.com
export ETHEREUM_JSONRPC_HTTP_URL=<your polygon-edge json-rpc endpoint>
# example: ETHEREUM_JSONRPC_TRACE_URL=https://rpc-testnet.alveychain.com
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:Passw0Rd@db.instance.local:5432/blockscout
export DATABASE_URL=postgresql://<db_user>:<db_pass>@<db_host>:<db_port>/<db_name>
# secret key base as per docs https://docs.blockscout.com/for-developers/manual-deployment ( Step 4 )
export SECRET_KEY_BASE=VTIB3uHDNbvrY0+60ZWgUoUBKDn9ppLR8MI4CpRz4/qLyEFs54ktJfaNT6Z221No
# we set these env vars to test the db connection
export PGPASSWORD=Passw0Rd
export PGUSER=blockscout
export PGHOST=db.instance.local
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:
psql
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.
blockscout=>
Otherwise you might see an error like this:
psql: error: FATAL: password authentication failed for user "blockscout"
FATAL: password authentication failed for user "blockscout"
:::info DB Connection 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. :::
postgres@ubuntu:~$ 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
cd ~
git clone https://github.com/poanetwork/blockscout.git
Compile
Cd into clone directory and start compiling
cd blockcout
mix local.hex --force
mix do deps.get, local.rebar --force, deps.compile, compile
Migrate databases
:::info 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.
cd apps/block_scout_web/assets
sudo npm install
sudo node_modules/webpack/bin/webpack.js --mode production
:::info Be patient 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.
cd ~/blockscout
sudo mix phx.digest
Generate self-signed certificates
cd apps/block_scout_web
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:
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
:::info 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 )
ETHEREUM_JSONRPC_HTTP_URL=https://rpc-testnet.alveychain.com
ETHEREUM_JSONRPC_TRACE_URL=https://rpc-testnet.alveychain.com
DATABASE_URL=postgresql://blockscout:Passw0Rd@db.instance.local:5432/blockscout
SECRET_KEY_BASE=VTIB3uHDNbvrY0+60ZWgUoUBKDn9ppLR8MI4CpRz4/qLyEFs54ktJfaNT6Z221No
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:
Blockscout web service runs by default on ports 4000(http) and 4001(https). If everythig is ok, you should be able to access the Blockscout web portal with http://<host_ip>:4000 or https://<host_ip>:4001
Final thoughts
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.
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
If this is the case might help you.
You should definitely checkout the official as there a lot of customisation options.
