Feather Core

Feather Core is a template blockchain built using Cosmos SDK and CometBFT and created with the Feather CLI. It is meant to be used together with Feather 🪶.

Features

• All default Cosmos SDK modules
• The Cosmos IBC module
• The Osmosis Token Factory module
• The Terra Alliance module

Installation

Install dependencies:

• go
• jq
• make
• gcc

Build and install the chain binary:

# Run this in the repo root, where README.md lives.
feather dev build

Developing

Check for correctness by running chain simulations:

# Run in repo root
feather dev simulate

Initialize configs to start the chain (for local testing):

# Run in repo root
feather dev sandbox init

# Start the chain (your binary name may differ)
feather-cored start

Configuration

For Development

Configure the config/localnet/config.json file if you want to test run your chain before deploying to production with Feather.

{
    # Should uniquely identify your blockchain network.
    # Naming convention: `[-a-zA-Z0-9]{3,47}`
    "chain_id": "test-chain",
    # List of genesis accounts, with their bank balances at genesis.
    "accounts": [
        {
            "name": "alice",
            "coins": [
                {
                    "denom": "token",
                    "amount": "20000"
                },
                {
                    "denom": "stake",
                    "amount": "200000000"
                }
            ]
        },
        {
            "name": "bob",
            "coins": [
                {
                    "denom": "token",
                    "amount": "10000"
                },
                {
                    "denom": "stake",
                    "amount": "100000000"
                }
            ]
        }
    ],
    # List of genesis validators, with their staked coins at genesis.
    "validators": [
        {
            "name": "alice",
            "bonded": {
                "denom": "stake",
                "amount": "100000000"
            }
        }
    ]
}

For Production

Configure the config/mainnet/config.json if you would like to do any of the following:

1. Change the default bond denom of the chain.
2. Change the name of the chain and chain binary.
3. Change the address prefixes of user accounts, validator accounts or consensus accounts.
4. Change parameters from the x/staking module when the chain is deployed by Feather.
5. Configure the LCD/RPC/Prometheus endpoints when the chain is deployed by Feather.

{
    # Actual chain id when chain is deployed by Feather.
    "chain_id": "feather-1",
    # Name of the chain and chain binary (suffixed with 'd').
    "app_name": "feather-core",
    # Metadata registered in the cosmos sdk package.
    "app_binary_name": "feather-cored",
    # Address prefixes
    "account_address_prefix": "pfeath",
    "account_pubkey_prefix": "pfeathpub",
    "validator_address_prefix": "pfeathvaloper",
    "validator_pubkey_prefix": "pfeathvaloperpub",
    "consensus_node_address_prefix": "pfeathvalcons",
    "consensus_node_pubkey_prefix": "pfeathvalconspub",
    # Staking bond denominator (i.e. coin currency used for staking)
    "bond_denom": "stake",
    # Amount of bond denom for staking available at genesis.
    # This is split among approved genesis validators by Feather.
    "bond_supply": "1000000000",
    # Cooldown time after unbonding from a validator before an account can stake again.
    "unbonding_time": "1814400s",
    # Max number of validators the chain supports.
    "max_validators": 130,
    "max_entries": 7,
    "min_commission_rate": "0",
    # Whether to start the LCD server with the chain.
    "lcd_enabled": true,
    # Exposes a swagger page documenting exposed API endpoints at IP:<lcd_port>.
    "lcd_swagger_enabled": true,
    # Configurable LCD server port.
    "lcd_port": 1317,
    # Enable this if querying the blockchain from a CORS-enabled app, like web browsers.
    "lcd_enable_unsafe_cors": false,
    # Whether to start the RPC server with the chain.
    "rpc_enabled": true,
    # Configurable RPC server port.
    "rpc_port": 26657,
    # Whether to enable Prometheus metrics.
    "prometheus_enabled": true,
    # Configurable Prometheus port.
    "prometheus_port": 26660
}

Publishing

You must publish your chain with Feather for other Feather users to discover and deploy validators for your chain.

# Before publishing your chain, it must be publicly available
export REPO="https://github.com/<YourName>/<your-repo>"
git init
git remote add origin $REPO
git branch -M main
git push -u origin main

# Import your existing terra account using your seed phrase (must have LUNA in testnet)
# Request LUNA from testnet https://faucet.terra.money if needed.
export KEY='mykey'
feather config keys add $KEY --recover --hd-path="m/44'/330'/0'/0/0"

# Publish your chain
# export LAUNCH_TIME=$(date -d '+1 day' +%s) # Linux users
export LAUNCH_TIME=$(date -v +1d +%s)        # MacOS users
feather prod chains publish --key $KEY --launch-time $LAUNCH_TIME --repo $REPO

# Note down the printed launch id...

# Query your chain
export LAUNCH_ID="<launch_id>"
feather prod chains show $LAUNCH_ID

Approving join requests

Feather validators may submit a gentx request to join your chain as a validator. Feather will only include approved validators in the final deployed chain.

export LAUNCH_ID='<launch_id>'
export KEY='<key>'

# list requests to join a chain for a launch id
feather prod requests pull $LAUNCH_ID

# approve a validator for a given chain launch
export REQUEST_ID='<request_id>'
feather prod requests approve --key $KEY --launch-id $LAUNCH_ID --request-id $REQUEST_ID

Interface

Feather Core must adhere to this interface to work correctly with Feather. Feather will not launch your chain if it fails the interface verification.

• Do not change the root Makefile. Use a non-standard makefile name with the -f or --file option if you need one for your own needs.
• Do not change the location of the main package (must be in cmd/<app_name>)
• Do not change the location of the simulation_test.go file. (must be app/simulation_test.go)
• Do not change the contents of the simulation_test.go file.
• Do not change the location of the files under the root config directory.