Compute utilization rate using internally-tracked parameters #180
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| deps: &DepsMut, | ||
| env: &Env, | ||
| market: &mut Market, | ||
| liquidity_taken: Uint128, |
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In the previous implementation, where utilization is computed based on the contract's coin balance, we need to subtract the amount of coins that will be sent out.
In this new implementation, we don't need this anymore, because the internally tracked params (collateral_total_scaled and liquidity_index) have already been properly updated in the apply_accumulated_interests function.
| env: &Env, | ||
| market: &mut Market, | ||
| liquidity_taken: Uint128, | ||
| denom: &str, |
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We also don't need this denom, which is already provided by market.denom
| if contract_current_balance < liquidity_taken { | ||
| return Err(ContractError::OperationExceedsAvailableLiquidity {}); | ||
| } |
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We don't really need to check whether "operation exceeds available liquidity". If it does, the bank send message will fail.
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True, but I wonder if this will later make it harder to know why the transaction fails. Error messaging already vague as is in deployed contracts.
| let debt_total_scaled = | ||
| compute_scaled_amount(asset_initial_debt, Decimal::one(), ScalingOperation::Ceil).unwrap(); | ||
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| let asset_initial_collateral = asset_liquidity + asset_initial_debt; | ||
| let collateral_total_scaled = | ||
| compute_scaled_amount(asset_initial_collateral, Decimal::one(), ScalingOperation::Ceil) | ||
| .unwrap(); | ||
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| let initial_utilization_rate = Decimal::from_ratio(debt_total_scaled, collateral_total_scaled); | ||
| let borrow_rate = ir_model.get_borrow_rate(initial_utilization_rate).unwrap(); | ||
| let liquidity_rate = | ||
| ir_model.get_liquidity_rate(borrow_rate, initial_utilization_rate, reserve_factor).unwrap(); |
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Previously this test wasn't set up properly: the collateral_total_scaled was uninitialized (default to zero), and borrow/liquidity rates were just some made up numbers that do not correspond to the utilization rate.
Now, in order for the test to pass, we need to actually choose the logical values for these parameters.
I consider this a win - it forces us to improve the quality of our tests!
| // in this particular example, we have to subtract 1 from the total underlying | ||
| // collateral amount here, because of rounding error. | ||
| let expected_collateral = expected_liquidity + expected_debt - Uint128::new(1); | ||
| let expected_utilization_rate = Decimal::from_ratio(expected_debt, expected_collateral); |
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The rounding error happens when converting the collateral's scaled amount to the underlying amount. Here I manually subtract the expected underlying amount by 1 to reflect the error. Not sure if there's a better way.
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| if contract_current_balance < liquidity_taken { | ||
| return Err(ContractError::OperationExceedsAvailableLiquidity {}); | ||
| } |
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True, but I wonder if this will later make it harder to know why the transaction fails. Error messaging already vague as is in deployed contracts.
* Mp 2422 emergency role improve (#185) * Mp 2460 reject unexpected payment (#186) * Compute utilization rate using internally-tracked parameters (#180) * Update owner pkg to 1.2.0 (#198) Co-authored-by: larry <26318510+larry0x@users.noreply.github.com> Co-authored-by: Gabe Rodriguez <grod220@gmail.com>
* Mp 2422 emergency role improve (#185) * Mp 2460 reject unexpected payment (#186) * Compute utilization rate using internally-tracked parameters (#180) * Update owner pkg to 1.2.0 (#198) Co-authored-by: larry <26318510+larry0x@users.noreply.github.com> Co-authored-by: Gabe Rodriguez <grod220@gmail.com> Signed-off-by: Pacman <pacman@apollo.farm>
* Add liquidation_related flag for withdraw. It is used by credit manager to indicate liquidation. * Fix cargo audit. * Use correct commit from red-bank. * Update schema. * Use --locked for grcov install.
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