Problem

Problem:
The eth_getBalance method in packages/relay/src/lib/eth.ts currently allows the second parameter blockNumberOrTagOrHash to be null, as indicated by its TypeScript type:

blockNumberOrTagOrHash: string | null

However, the method is decorated with @rpcParamValidationRules enforcing this parameter as required:

@rpcParamValidationRules({
  0: { type: ParamType.ADDRESS, required: true },
  1: { type: ParamType.BLOCK_NUMBER_OR_HASH, required: true },
})

This mismatch is inconsistent with Ethereum's openrpc.json, where the Block parameter is required and must conform to the BlockNumberOrTagOrHash schema.

In contrast, the Hedera-specific OpenRPC spec allows the parameter to be optional, but for Ethereum compatibility, we must follow the Ethereum spec.

Solution

• Update the implementation of getBalance to no longer allow null for the blockNumberOrTagOrHash parameter:

  blockNumberOrTagOrHash: string

• Ensure the entire code path respects the required status of this parameter and gracefully handles cases where it's missing or invalid.

• Add or update unit tests to confirm that a missing or null blockNumberOrTagOrHash leads to validation errors, aligning behavior with Ethereum JSON-RPC expectations.

Alternatives

No response