Oracle Price Feeder

Setting up the oracle price feeder is necessary for validators.

Exocore relies on an external price oracle to determine the total vote power for each validator, who may be staking multiple assets. Validators are required to run a price feeder to participate in the network, which periodically fetches prices from data sources and submits them to the oracle module. Failing to run the price feeder tool results in penalties like jailing and slashing.

Before you start, make sure to set in grpc.enable = true in app.toml, as previously advised.

There are two methods to run the price feeder tool. The first method is recommended for most validators, while the second method is suited for the more technical and risk-averse validators.

Option 1: Embedded version

1. Set up the configuration of the price feeder tool. It requires three files: the first for its own configuration, the second for the price sources and the last for native restaking.

   $HOMEDIR/config/oracle_feeder.yaml

   sources:
     chainlink
   tokens:
     - ETHUSDT
     - WSTETHUSDT
     - USDCUSDT
     - NSTETH
   sender:
     path: "$HOMEDIR/config" # actual value not `$HOMEDIR`
   exocore:
     chainid: exocoretestnet_233-7
     appName: exocore
     rpc: 127.0.0.1:9090
     ws:
       addr: !!str ws://127.0.0.1:26657
       endpoint: /websocket

   The prices are sourced from Chainlink contracts on Ethereum, so you’ll need an RPC URL from providers like Alchemy and Infura or a self-hosted version.

   $HOMEDIR/config/oracle_env_chainlink.yaml

   urls:
     mainnet: !!str https://rpc.ankr.com/eth/
     sepolia: !!str https://rpc.ankr.com/eth_sepolia/
   tokens:
     ETHUSDT: 0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419_mainnet
     WSTETHUSDT: 0xaaabb530434B0EeAAc9A42E25dbC6A22D7bE218E_sepolia
     USDCUSDT: 0x8fFfFfd4AfB6115b954Bd326cbe7B4BA576818f6_mainnet

   To support native restaking on Holesky, another file is used.

   $HOMEDIR/config/oracle_env_beaconchain.yaml

   url:
     # This needs a paid Ankr subscription. Alternatively, check the validator
     # channel for an internal-use-only Holesky endpoint that we provide for
     # our testnet validators.
     !!str https://rpc.ankr.com/premium-http/eth_holesky_beacon/${YOUR_API_KEY}
   nstid:
     !!str 0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee_0x9d19

2. Run your validator as described on the next page.

Option 2: As an independent binary

This option is designed for validators who would like to decouple the two processes for security and/or reliability.

1. Download and save the price feeder tool to a location within $PATH.

   VERSION="0.1.15"
   wget -O price-feeder_${VERSION}.tar.gz "https://github.com/ExocoreNetwork/price-feeder/releases/download/v${VERSION}/price-feeder_${VERSION}_$(uname -s)_$(uname -m | sed 's/x86_64/amd64/' | sed 's/aarch64/arm64/').tar.gz"
   tar -xvzf price-feeder_${VERSION}.tar.gz
   mv bin/price-feeder /usr/bin/

2. Set up its configuration as described under Option 1 Step 1.

3. Start the price feeder tool

   price-feeder start --config $HOMEDIR/config/oracle_feeder.yaml --sources $HOMEDIR/config/

4. If everything works, productionize the process with systemd or another tool of your choice and keep it running. The expected logs are shown below.

   2024/09/11 18:02:04 Triggered, height:31, feeder-parames:{feederID:1, startBlock:20, interval:10, roundID:1}:
   2024/09/11 18:02:04 price not changed, skip submitting price for roundID:2, feederID:1