KERI Registrar Backer on Cardano

A KERI witness that anchors key events on Cardano blockchain.

Feaures

• Cardano Address is derived from the same Ed25519 seed (private key) used to derive the prefix of the backer
• Anchoring KELs from multiple prefixes
• Queue events during a period of time to allow several block confirmations as a safety meassure
• Optional funding address to fund the backer address

Previous and related work

• keri-roots
• original keripy PR

Installation

pip install -e .

Check installation and available commands:

$ backer --help
usage: backer [-h] command ...

options:
  -h, --help  show this help message and exit

subcommands:

  command
    info      Display registrar backer information
    query     Query KEL on ledger for a given prefix
    start     Runs KERI backer controller

Start script example

./scripts/start_backer.sh

Check variables and environmental variables that you can pass to configure the backer.

Environment variables

WALLET_ADDRESS_CBORHEX

This environmental variable is used by backer to provide the Private Key of spending address as CBOR Hex. Must be an Enterprice address (no Staking part) as PaymentSigningKeyShelley_ed25519. Note that storing private keys in an environmental variable is highly insecure !

BACKER_CONFIG_DIR

This environmental variable is used by start_backer.sh script to specify the directory to place the configuration files.

BACKER_STORE_DIR

This environmental variable is used by start_backer.sh script to specify the directory to create the database and keystore.

BACKER_URL

This environmental variable is used by start_backer.sh script to specify the URL of the backer needed to resolve OOBI and to receive queries from the agents.

BACKER_PORT

This environmental variable is used by start_backer.sh script to specify the PORT of the backer needed to resolve OOBI and to receive queries from the agents.

BACKER_SALT

This environmental variable is used by start_backer.sh script that passes it to the kli init as a SALT parameter. It's a qualified base64 salt for creating key pairs, that means that you can regenerate a backer with same AID and Cardano address.

Docker

See DOCKER.md for instructions on how to deploy using Docker.

Development

Creating a local devnet with Yaci DevKit

Yaci DevKit: A set of development tools for building on Cardano by creating a local devnet.

Pre-requisites

• Download yaci-cli and commponents by executing this script

./yaci-cli/download-components.sh

Start default yaci devnet

./yaci-cli/start-devnet.sh

After executing start-devnet.sh, a default devnet will be created. Here are the default services

• WALLET_ADDRESS_CBORHEX: 5820339f8d1757c2c19ba62146d98400be157cdbbe149a4200bd9cc68ef457c201f8
• SPENDING_ADDRESS: addr_test1vrs5guudp8u6ryqmt4etlhkmgcr6qld7lc0y22r73amjtvqsqphu8
• Started ogmios : http://localhost:1337
• Started submit api : http://localhost:8090
• Swagger Url to interact with the cluster's node : http://localhost:10000/swagger-ui.html

Stop default yaci devnet

./yaci-cli/stop-devnet.sh

Customize and setup advanded devnet

./yaci-cli/yaci-cli

Yaci CLI - Few Key Commands

This section explains a few key commands specific to Yaci CLI.

Create a default devnet

yaci-cli:>create-node

To overwrite data or reset the existing default devnet, use the "-o" flag. Use --start flag to start the devnet after creation.

yaci-cli:>create-node -o
or,
yaci-cli:>create-node -o --start

Known Issue: Yaci DevKit uses a share folder to store the data on host machine. In some setup, this causes issue due to permission. If you face similar issue and not able to start the devnet, you can remove volumes section from docker-compose.yml file and restart the docker compose. It should work fine and create the devnet data in the docker container itself. Please check this issue for more details.

Create a default devnet node with Conway Era

By default, Yaci DevKit creates a devnet with Babbage era. If you want to create a devnet with Conway era, use the following command.

yaci-cli:>create-node -o --era conway

Create a devnet with custom slots per epoch

To create devnet with a custom slots per epoch (By default 500 slots/epoch)

For example: Create and start a devnet with 30 slots per epoch

yaci-cli> create-node -o -e 30 --start

Now, you should be in the "devnet" context. To start the devnet, use the "start" command.

devnet:default>start

Note Now, with Yaci Viewer, you can conveniently check the devnet's data right from the browser. Simply open the following URL in your browser to access the Yaci Viewer.

http://localhost:5173

To reset cluster's data

If your devnet gets stuck or you simply want to reset the data and restart with the same configuration, simply use the command "reset". It will restore your devnet to its initial state, allowing you to continue your development seamlessly.

devnet:default>reset

To stop

devnet:default>stop

To fund a new address

Easily fund your test account with ADA using the "topup" command.

devnet:default> topup <address> <ada value>

To check utxos at an address

devnet:default> utxos <address>

To get default addresses

devnet:default> default-addresses

To check devnet and url info

devnet:default> info

For more details about Yaci CLI, please check https://yaci-cli.bloxbean.com .