Omniscia Nexera Protocol Audit
GenericSingleDatasetSubscriptionManager Code Style Findings
GenericSingleDatasetSubscriptionManager Code Style Findings
GSD-01C: Ineffectual Usage of Safe Arithmetics
| Type | Severity | Location |
|---|---|---|
| Language Specific |  | GenericSingleDatasetSubscriptionManager.sol:L133, L310, L311, L328 |
Description:
The linked mathematical operations are guaranteed to be performed safely by surrounding conditionals evaluated in either require checks or if-else constructs.
Example:
133return (newFee > currentFee) ? (newFee - currentFee) : 0;Recommendation:
Given that safe arithmetics are toggled on by default in pragma versions of 0.8.X, we advise the linked statements to be wrapped in unchecked code blocks thereby optimizing their execution cost.
Alleviation (fb50b5c39665f7df086b2de1fdbf93ba2d836bf9):
All referenced arithmetic statements have been safely wrapped in an unchecked code block, optimizing each code block's gas cost.
GSD-02C: Inefficient Loop Limit Evaluation
| Type | Severity | Location |
|---|---|---|
| Gas Optimization | | GenericSingleDatasetSubscriptionManager.sol:L93 |
Description:
The linked for loop evaluates its limit inefficiently on each iteration.
Example:
93for (uint256 i; i < subscrs.length(); i++) {Recommendation:
We advise the statements within the for loop limit to be relocated outside to a local variable declaration that is consequently utilized for the evaluation to significantly reduce the codebase's gas cost. We should note the same optimization is applicable for storage reads present in such limits as they are newly read on each iteration (i.e. length members of arrays in storage).
Alleviation (fb50b5c39665f7df086b2de1fdbf93ba2d836bf9):
The referenced loop limit evaluation (subscrs.length()) has been properly cached outside the for loop to a dedicated local variable totalSubscribers that is consequently utilized, optimizing the loop's gas cost significantly.
GSD-03C: Inexistent Event Indexing
| Type | Severity | Location |
|---|---|---|
| Language Specific | | GenericSingleDatasetSubscriptionManager.sol:L22-L24 |
Description:
The SubscriptionPaid, ConsumerAdded, and ConsumerRemoved events of the GenericSingleDatasetSubscriptionManager contract do not contain any indexed arguments.
Example:
22event SubscriptionPaid(uint256 id, uint256 validSince, uint256 validTill, uint256 paidConsumers);23event ConsumerAdded(uint256 id, address consumer);24event ConsumerRemoved(uint256 id, address consumer);Recommendation:
We advise them to be introduced, particularly in relation to the id as well as consumer to ensure off-chain processes can optimally filter these events.
Alleviation (fb50b5c39665f7df086b2de1fdbf93ba2d836bf9):
The indexed keyword has been properly introduced to the id and consumer values as advised, optimizing their off-chain usability.
GSD-04C: Loop Iterator Optimizations
| Type | Severity | Location |
|---|---|---|
| Gas Optimization | | GenericSingleDatasetSubscriptionManager.sol:L93, L348, L368, L394 |
Description:
The linked for loops increment / decrement their iterator "safely" due to Solidity's built - in safe arithmetics (post-0.8.X).
Example:
93for (uint256 i; i < subscrs.length(); i++) {Recommendation:
We advise the increment / decrement operations to be performed in an unchecked code block as the last statement within each for loop to optimize their execution cost.
Alleviation (fb50b5c39665f7df086b2de1fdbf93ba2d836bf9):
The referenced loop iterator increment statements have been relocated at the end of each respective for loop's body and have been unwrapped in an unchecked code block, optimizing their gas cost.
GSD-05C: Repetitive Value Literals
| Type | Severity | Location |
|---|---|---|
| Code Style | | GenericSingleDatasetSubscriptionManager.sol:L114, L272, L300, L310, L311 |
Description:
The linked value literals are repeated across the codebase multiple times.
Example:
114if (durationInDays == 0 || durationInDays > 365) revert SUBSCRIPTION_DURATION_INVALID(1, 365, durationInDays);Recommendation:
We advise each to be set to its dedicated constant variable instead optimizing the legibility of the codebase.
Alleviation (fb50b5c39665f7df086b2de1fdbf93ba2d836bf9):
The referenced value literals 365, and 30 have all been relocated to contract-level constant declarations labelled MAX_SUBSCRIPTION_DURATION_IN_DAYS, and MAX_SUBSCRIPTION_EXTENSION_IN_DAYS respectively, optimizing the code's legibility.