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Logging levels and formats can be configured for Hyperlane tooling using the following two environment variables:

  • LOG_LEVEL: The log level to filter to. Defaults to info. Choices: debug | info | warn | error | off
  • LOG_FORMAT: The format of the log output. Defaults to pretty. Choices: pretty | json

The Hyperlane CLI also allows configuring logging via the --log and --verbosity flags.

Chain configuration

Within your working directory, you may find a chains/ yaml files organized by chain name. These metadata.yaml files describe the information needed to use the chain in Hyperlane deployments and apps.

You can define a full configuration for any new chain in this file. The metadata that can be configured is defined in this example configuration. You can also find the chain metadata schema at chainMetadataTypes.ts.

Here's an example configuration for two local anvil chains:

chainId: 31337
domainId: 31337
name: anvil1
protocol: ethereum
- http: http://localhost:8545
name: Ether
symbol: ETH
decimals: 18
chainId: 31338
domainId: 31338
name: anvil2
protocol: ethereum
- http: http://localhost:8555

You can also extend a core chain config by providing the fields to be overridden:

confirmations: 2

Override RPC URLs

You can override the RPC urls by extending the core chain config.

In the example below, you can see how to define an array of RPCs and also adjust the retry parameters for any of them.

name: demochain
chainId: 123456
domainId: 123456
protocol: ethereum
- http:
- http:
- http:
maxRequests: 10

Override transaction settings

Transaction overrides are any properties to include when forming transaction requests. For example:

  • gasPrice: number | string
  • maxFeePerGas: number | string
  • maxPriorityFeePerGas: number | string
  • nonce: number | string
  • type: number
  • ccipReadEnabled: boolean

In the example below we're using a gas price of 7 gwei, hardcoding the nonce, and setting a maximum value for the base and priority fees.

gasPrice: 7000000000 # 7 gwei
maxFeePerGas: 150000000000 # 150 gwei
maxPriorityFeePerGas: 40000000000 # 40 gwei
nonce: 1337

If you are overriding the nonce in the chain configuration, ensure you are updating the value on successful transactions.