2.3 Blockchain explorer: BTC RPC Explorer

Requirements

• Others

Introduction

Preparations

Install Node + NPM

• With user admin, check if you have already installed Node

Example of expected output:

• Check if you have already installed NPM

Example of expected output:

-> If the "node -v" output is >=18, you can move to the next section.

• Update and upgrade your OS

• Install the next dependency package. Press "y" and enter or directly enter when the prompt asks you

Reverse proxy & Firewall

Enable the Nginx reverse proxy to route external encrypted HTTPS traffic internally to the BTC RPC Explorer. The error_page 497 directive instructs browsers that send HTTP requests to resend them over HTTPS.

• With user admin, create the reverse proxy configuration

• Paste the complete following configuration. Save and exit

• Create the symbolic link that points to the directory sites-enabled

• Test Nginx configuration

Expected output:

• Reload the Nginx configuration to apply changes

• Configure the firewall to allow incoming HTTPS requests

Installation

Create the btcrpcexplorer user & group

For improved security, we will create a new user btcrpcexplorer that will run the block explorer. Using a dedicated user limits potential damage in case there's a security vulnerability in the code. An attacker could not do much within this user's permission settings. We will install BTC RPC Explorer in the home directory since it doesn't need too much space.

• Create the btcrpcexplorer user and group

• Add btcrpcexplorer user to the "bitcoin" group, allowing to the btcrpcexplorer user read the bitcoind .cookie file

• Change to the new btcrpcexplorer user

• Set a temporary version environment variable to the installation

• Import the GPG key of the developer

• Download the source code directly from GitHub and go to the btc-rpc-explorer folder

• Verify the release

Example of expected output:

• Install all dependencies using NPM

Installation can take some time, be patient. There might be a lot of confusing output, but if you see something similar to the following, the installation was successful

Example of expected output:

• Check the correct installation by requesting the version

Example of expected output:

Configuration

• Copy the configuration template

• Edit the .env file.

Activate any setting by removing the # at the beginning of the line or editing directly

• Instruct the BTC RPC Explorer to connect to the local Bitcoin Core

• To get address balances, either an Electrum server or an external service is necessary. Your local Electrum server can provide address transaction lists, balances, and more

• Uncomment this line

• Save and exit

• Exit the btcrpcexplorer user session to return to the admin user session

Create systemd service

Now we'll make sure our blockchain explorer starts as a service on the PC so that it's always running.

• As user admin, create the service file

• Paste the following configuration. Save and exit

• Enable autoboot (optional)

• Prepare "btcrpcexplorer" monitoring by the systemd journal and check the logging output. You can exit monitoring at any time with Ctrl-C

Run

• Start the service

Example of expected output on the first terminal with journalctl -fu btcrpcexplorer ⬇️

Now point your browser to the secure access point provided by the NGINX web proxy, for example, "https://minibolt.local:4000" (or your node IP address) like "https://192.168.x.xxx:4000". You should see the home page of BTC RPC Explorer

Your browser will display a warning because we use a self-signed SSL certificate. We can do nothing about that because we would need a proper domain name (e.g. https://yournode.com) to get an official certificate that browsers recognize. Click on "Advanced" and proceed to the Block Explorer web interface

If you see a lot of errors on the MiniBolt command line, then Bitcoin Core might still be indexing the blockchain. You need to wait until reindexing is done before using the BTC RPC Explorer

• Ensure the service is working and listening at the default 3002 port and the HTTPS 4000 port

Expected output:

Congrats! Now you have a Blockchain Explorer: BTC RPC Explorer running to check the Bitcoin network information directly from your node

Extras (optional)

Privacy

You can decide whether you want to optimize for more information or more privacy.

• With user admin user, edit the .env configuration file

• More privacy mode, no external queries

• More information mode, including Bitcoin exchange rates

• Save and exit

Security

You can add password protection to the web interface. Simply add your password [D] for the following option, for which the browser will then prompt you. You can enter any user name; only the password is checked

• With user admin user, edit the .env configuration file

• Replace the next line. Save and exit

Theme

Decide whether you prefer a light or dark theme by default

• With user admin user, edit the .env configuration file

• Uncomment and replace this line with your selection. Left uncommented to dark (default is dark). Save and exit

Slow device mode (resource-intensive features are disabled)

Extend the timeout period and enable slow device mode due to the limited resources

• With user admin user, edit the .env configuration file

• Uncomment and change the value of this line

• Comment this line if it is uncommented (default value is true). Save and exit

Sharing your explorer

• With user admin user, edit the .env configuration file

• Uncomment this line

-> Remember to give them the password [D] if you added password protection in the reference step

With DEMO mode enabled, the user will see the next message:

"Sorry, that RPC command is blacklisted. If this is your server, you may allow this command by removing it from the 'rpcBlacklist' setting in config.js."

Remote access over Tor

Do you want to access your personal blockchain explorer remotely? You can easily do so by adding a Tor hidden service on the MiniBolt and accessing the BTC RPC Explorer with the Tor browser from any device.

• With the user admin , edit the torrc file

• Add the following lines in the "location hidden services" section, below "## This section is just for location-hidden services ##" in the torrc file. Save and exit

• Reload the Tor configuration

• Get your Onion address

Example of expected output:

Upgrade

• With admin user, stop the service

• Change to the btcrpcexplorer user

• Set a temporary version environment variable to the installation

• Go to the btc-rpc-explorer folder

• Fetch the latest GitHub repository information

• Display the release tags (use the latest in this example)

• Install dependencies

• Come back to the admin user

• Start the service again

Uninstall

Uninstall service

• With the user admin , stop btcrpcexplorer

• Disable autoboot (if enabled)

• Delete the service

Delete user & group

• Delete the btcrpcexplorer user. Do not worry about the userdel: btcrpcexplorer mail spool (/var/mail/btcrpcexplorer) not found

Uninstall Tor hidden service

• Ensure that you are logged in with the user admin and delete or comment on the following lines in the "location hidden services" section, below "## This section is just for location-hidden services ##" in the torrc file. Save and exit

• Reload the tor to apply changes

Uninstall reverse proxy & FW configuration

• Ensure you are logged in with the user admin, delete the reverse proxy config file

• Delete the simbolic link

• Test Nginx configuration

Expected output:

• Reload the Nginx configuration to apply changes

• Display the UFW firewall rules, and note the numbers of the rules for BTC RPC Explorer (e.g. "Y" below)

Expected output:

• Delete the rule with the correct number and confirm with "yes"

Port reference