Get Cardano stake pool snapshot data at the end of the epoch using the Koios API and store it in a local SQLite database.
You need SQLite and Node.js installed on your system. For a Debian/Ubuntu-based system you can install those by running this command:
sudo apt install sqlite3 nodejs
Clone the repository and enter the snapshotter directory. Open the snapshotter.js file and set the koiosApiKey to your API key.
To install the package dependencies, run:
npm install
Create the database schema:
cat schema.sql | sqlite3 snapshotter.sqlite
Create a systemd timer and service as displayed below. The systemd timer will trigger daily, but the snapshotter.js script will only insert the snapshot data on the last day of the epoch.
/etc/systemd/system/snapshotter.timer
-------------------------------------------------
[Unit]
Description=Periodic run of snapshotter.js
[Timer]
OnCalendar=*-*-* 21:35:00 UTC
Unit=snapshotter.service
[Install]
WantedBy=timers.target
Change the ExecStart and Workingdirectory paths in the service unit below to point to your snapshotter.js file and it's containing directory.
/etc/systemd/system/snapshotter.service
-------------------------------------------------
[Unit]
Description=Snapshotter.js
[Service]
Type=oneshot
ExecStart=/usr/bin/node /path/to/snapshotter.js
WorkingDirectory=/path/to
[Install]
WantedBy=multi-user.target
Enable and start the timer:
sudo systemctl enable --now snapshotter.timer
You can also run the program manually on any day of the epoch by using the -f argument. To save a snapshot for any other epoch than the current, use i.e. -e 450.