Dev Update #12

Hey

in my last update I discussed the first part of the attestation_rewards endpoint, the ideal_rewards. In this update, I want to focus on the second and last part, the total_rewards.

{
  "execution_optimistic": false,
  "finalized": false,
  "data": [
    {
      "ideal_rewards": [
        {
          "effective_balance": "1000000000",
          "head": "2500",
          "target": "5000",
          "source": "5000"
        }
      ],
      "total_rewards": [
        {
          "validator_index": "0",
          "head": "2000",
          "target": "2000",
          "source": "4000",
          "inclusion_delay": "2000"
        }
      ]
    }
  ]
}

total_rewards

The total_rewards describe the actual rewards a validator receives through attestations. To rephrase the logic I already explained in earlier development updates:

• Determine if the validator is eligible for rewards in the chosen epoch. If not, their reward is 0.
• Determine if the validator voted correctly for the flag (head,target, and source).
  • If the validator voted correctly, their reward is based on the combination of the flag and their effective_balance.
  • If the validator voted incorrectly, their reward is calculated differently depending on the flag:
    • For the head vote, the reward is 0.
    • For the target and source votes, the reward is a negative value calculated by multiplying the base reward by the weight and dividing by a certain value.

My current implementation for the total_rewards looks like the following:

let index = participation_cache.eligible_validator_indices();

for validator_index in index {
    let eligible = match state.is_eligible_validator(previous_epoch, *validator_index) {
        Ok(eligible) => eligible,
        Err(_) => return Err(warp_utils::reject::custom_server_error("Unable to get eligible".to_owned())),
    };
    let total_reward = if !eligible {
        0u64
    } else {
        let voted_correctly = participation_cache.get_unslashed_participating_indices(flag_index, previous_epoch).is_ok();
        if voted_correctly {
            *ideal_rewards.get(&(&flag_index, effective_balance_eth)).unwrap_or(&0)
        } else {
            (-(base_reward as i64 as i128) * weight as i128 / WEIGHT_DENOMINATOR as i128) as u64
        }
    };

Next up

To be able to merge this endpoint, there are still some things left to do. I need to get the inclusion_delay, convert the HashMap of ideal_rewards into a Vector, test the API manually, and make minor optimizations.

Hopefully, I will be able to finish the attestation_rewards until the next update.