Hello @OmoEsther, great job on your project. I've went through your codebase and found a few minor issues. The changes I've made are :

Fixes and Improvements

1. Updated sdk version to prevent unexpected bugs and issues
2. Improved documentation of code by fixing typos and switching comments to Natspec
3. Added check when setting a new coffee price to prevent unexpected bugs and issues
4. Added checks in get_coffee_by_range and get_coffee_by_number to prevent queries of indexes that doesn't exist in the AllCoffee arrays to prevent bugs and issues

Overall, cool looking UI and idea. Have a nice week ahead.

Hello @Pasidalee, great job on your project. I've went ahead and looked through your codebase and found a few issues.

Fixes and Improvement

1. Removed the CTA buttons for registering a user and adding a candidate for everyone except the admin
2. Modified checks on the frontend and added checks on the smart contract to check inputs to prevent unexpected bugs/issues (wrong or empty accountId, registering a user below 18 yrs old etc)
3. Improved documentation of code by adding comments using the Nat spec format and renaming variables for better documentation (mostly the parameter id)
4. Refactored and removed redundant variables/imports
5. Minor fixes on the frontend that was giving errors (e.g key prop)
6. Modified the logic of adding voting to reduce gas costs by throwing early if sender isn't a valid voter
7. Modifed the setVoter to allow everyone to register themselves and also added the function ApproveVoter to verify voters that have just registered (I've added a Boolean verified to keep track of whether a user has been approved to vote)
8. Modified the vote function on the frontend to return a notification if user has already voted

As a side note, like Ashen already mentioned, the idea of operators could speed up the process of approving/registering voters onto the database. Good luck and have a great week ahead!

Hello @georgesimon, great job on your project. I've went ahead and looked through your codebase and noticed a few issues:

Fixes and Improvements

1. There were some typos on the frontend with the components which were causing the app to break (you also have not entered the contract name in config file and had a typo in marketplace.js file in the create function)
2. Improved documentation of code by adding additional comments in the Nat spec format
3. Modified dateAndTime into ends and deadlineRegister. Both will be used to implement checks to prevent users from registering on events that were already over but also allowed the owner of an event to delete his event before it was over
4. I've noticed that you were not saving the attendants array in Register to storage. I've fixed this issue and also added additional code to initialize the array if it was null but also to prevent users from registering twice
5. I've added the functionality RegisterAnotherUser to allow a user to pay for another user's registering fee for an event
6. I've added checks when creating an event to prevent unexpected behaviors/issues
7. I've added a check to prevent events' owners to change the location of an event after the deadline for registering as this could cause some participants to not have enough time to adapt and prepare for the new location
8. You could improve the checks that I've made by setting up required minimum guidelines (for e.g deadlineRegister and ends has to have a difference of at least 2 days)

Good luck and have a nice rest of your week

Hello Blisado, impressive project and submission. I've went ahead and looked through your smartcontract and found 2 bugs and some improvements to prevent unexpected issues/behaviors

Fixes and Improvements

1. Added additional comments wherever necessary(most for constants)
2. When admin was never initialized in the model with the argument passed through, instead context.predecessor was used. I've went ahead and mixed that
3. When transferring shares from an investor to another, the state of to wasn't updated (context.precedecessor was used twice)
4. In contributeToDAO function, I've replaced the logic of changes to contractParameters using the inherited method
5. I've noticed that when executing a proposal, the funds were not sent to the recipient while the balance of the smart contract was updated which could potentially lock the proposal's amount on the smart contract
6. I've added additional checks to make sure that quorum isn't above 100(since it is in percentage) to prevent unexpected behaviors/issues. Furthermore, I've added checks when transferring shares for the argument to to be a valid accountId. Finally, I've added a similar check for the recipient when creating a proposal
7. I've went ahead and made a few changes to the model of ContractParameters(I've added a locked variable that keeps track of funds locked in ongoing proposals) and Proposal (ended, success boolean variables). Additionally, I've created the method updateLocked which follow the same pattern to updateAvailableFunds and the endProposal method. I've also created the endProposal function in the index.ts file to allow the admin to end a proposal and make the necessary state changes and modified the executeProposal function to update the state of Locked and if the proposal was successful, funds are sent to the recipient of the proposal

Good luck and have a great weekend.

Hello 4undRaiser, great job on your submission. I've went ahead and looked through your code and only found a bug. I've went ahead and fixed that and made a few other changes:

Fixes and Improvements

1. Fixed issue of users being able to infinitely like by adding a mapping that keeps track of the quotes' ids liked by a user and a check
2. I've went ahead and added additional checks when adding a comment or creating a quote to prevent the quote's text and the comment's text to be empty as this could cause unexpected behaviors/issues on the frontend
3. Moved the logic of adding a comment into the model of Quote to be an inherited method for best practices
4. I've also modified the transfer of funds for donations to only get triggered if the attached deposit wasn't empty to save up on gas fees. Furthermore, I've added a variable in the model of Quote to keep track of the total amount collected from all donations on a quote
5. Fixed a few typos and switched comments to the Nat spec format for better documentation.

Overall great job and have a good weekend!

Hello @NbaHao, great job on your project. I've gone ahead and looked through your codebase and made a few changes:

Fixes

1. Added check the input data to make sure that it's a non-empty value
2. Added the variable owner and checks to make sure that only the task's owner can update or delete a task.

I'd also suggest you remove the node_modules folders in your project as they are unnecessary. Good luck and have a nice week!

hello @yami, great job on your UI and overally project. I've went ahead and tested your dapp and found a few minor issues:

Fixes and Improvements

1. Removed node_modules folder in the contract folder
2. I've added added the functionality to have an admin to safeguard posts from being able to be deleted by anyone
3. I've noticed that 0.1 NEAR was the amount set for donations, I've went ahead and implemented that on the smart contract
4. I've added checks to prevent empty content from comments or new posts
5. I've noticed that you have a variable that you are using for posts limit, I've went ahead and implemented a check to prevent more than 10 posts on the platform

Good luck and have a nice week ahead!

Hello @vuongvu, great job on your project. I've went through your code and made a few changes:

Fixes and Improvements

1. Added checks for number of tickets available when creating a Ticket, to prevent unexpected behaviors
2. Added checks for quantities when increasing and reducing number of tickets to prevent unexpected behaviors/bugs
3. Improved documentation of code by using natspec
4. Added check to prevent a Ticket event's owner from buying his own tickets
5. Moved functions making changes to the state of a Ticket event into methods of the class Ticket for best practices

Overall, great job and have a nice week ahead!

Hello @richiemike, great job on your project. I've went ahead and looked through your codebase and found a few issues.

Fixes and Improvement

1. Switched if statements that are used for checks into assert statements
2. Book owners could buy their own book, I've went ahead and fixed that by adding a check
3. Users could like a book as many times as they wanted, so I've made a few changes to fix that
4. I've removed the decreaseAvailableAmount since it was only used when buying a book, so I've the logic in incrementSoldAmount
5. I've added checks when changing the price and description to make sure that they were valid
6. Improved documentation of code by switching comments to the Nat spec format
7. I've added a function that lets users to retrieve the liked array (array containing the ids of books they liked), I'd suggest you implement it on the frontend to do things like hiding the like BTN on books users have already liked
8. Minor fixes on the frontend

Good luck and have a nice week ahead.

Hello @diego, great job on your submission. I've went through your code and found a few issues. The changes I've made are:

Fixes and Improvement

1. Added Config file for assembly
2. Added package json for smartcontract
3. Fixed errors you were having on the frontend in console (except the nesting errors around p)
4. Improved documentation of code by adding comments in the smart contract files
5. Simplified contract logic and moved changes made to an instance of Fundraise into its own functions
6. Added additional checks when donating to prevent unexpected bugs such as the attachedDeposit being less than the amount in the Donation object
7. Added the functionality to end a fundraise and added two new variables to the Fundraiser Class (ended and collected), to keep track of the amount collected and whether fundraise has been ended
8. Added new checks to prevent issues such as users being able to donate to a fundraise that has been ended
9. I've also made it so that the amount donated can only be withdrawn after collected is equal or greater than the amountNeeded

Good luck and have a nice weekend.

Hello @francess, great job on your project. I've gone ahead and tested your dapp and found a few minor issues:

Fixes and Improvements

1. Added additional checks for the input data when creating a new meal to prevent empty or invalid values as this could lead to issues on the front end. I've also added a check to make sure that the predecessor is an admin as only workers/owners of the restaurants should be able to add new meals to the menu
2. Added additional checks when deleting an order to make sure that the predecessor is the owner of that order as this could previously be misused. I've also noticed that you weren't removing the orderId from the userOrders' array and this could lead to potential issues where two users could potentially share the same orderIds.
3. Improved documentation of code by adding additional relevant comments

Good luck and have a nice rest of your week!

Hey Kiberu, seems like you forgot to include your smart contract in your Repo. This is important for the feedback process but also when evaluating. I've gone ahead and looked through your repos and managed to find it and upon reviewing it, here are some changes that I've made:

Fixes

1. Added validation checks for the input data to prevent invalid data as it could lead to unexpected behaviors and issues
2. Added an authentication check in clearlisting() to allow only the admin of the smart contract to clear all listings
3. Added an authentication check in deleteCoin() to allow only the coin's owner/seller to be able to remove the coin from the platform
4. Added checks in buyCoin to ensure that the quantity left for a coin can fulfill the amount ordered. I've also added a check to ensure that the amount attached to the transaction matches the total cost of to order.

Overall, good job on finishing the course, and have a nice rest of your week!

Hello @debbyy, great job on finishing the course. I've gone ahead and looked through your smart contract and found a few minor issues/improvements:

Fixes and Improvements

1. Cleanup of redundant functions and code that were essentially doing the same thing. I've gone ahead and grouped the code into one function(the rate functionalities)
2. Some typo fixes
3. I've added a mapping to keep track of sneakers rated by a user. This will prevent issues where a user is able to rate a sneaker more than once which can lead to misleading update of the state.

Good luck and have a nice weekend ahead!

Hey SamsonAmos, great job on your project. I've gone ahead and looked through your smart contract files and made a few changes:

Fixes

1. Fixed a few typos
2. Implemented validation checks for the input data when creating or updating a seed
3. I've added security checks to ensure that only authorized users can update or delete a seed.
4. I've noticed that the values assigned to the p variable in buySeed were essentially the data retrieved from a seed, so I've gone ahead and modified your code to use the retrieved seed to assign the required values.
5. Finally, I've ensured that the pId was unique before storing the purchased seed to avoid overwriting existing data.

Good luck and have a nice weekend!

Hello @motiv8, great job on finishing the challenge. I've went ahead and made some changes to your smartcontract as I've seen some rooms for improvements and there were also some issues.

Fixes and Improvements

1. Items' owners could buy their own items
2. Items allowed for trade could be exchanged with any other item (which could cause issues if one of the traded items' owners did not want to trade with that item), so I've went ahead and added a few new variables in the model Item to be able to implement the functions: requestExchange and rejectExchange while also modifying the exchangeGameItem function.
3. Moved any logic/code making changes to an item into the model Item as inherited methods for best practices
4. When buying an item, the owner was never switched. Furthermore, items could be both for exchange and on sale which could cause logistic issues as bought items could still be traded after being bought(unless the new owner toggles the exchange status).
5. When items were exchanged, the exchange status wasn't updated.
6. Added checks to prevent items on trade to be exchanged or items available to be exchanged to be on sale

Feel free to contract on Github/Discord if you have any questions about the changes I've made. Good luck and have a great week ahead!

Hello @Fahad, great job on your project. I've went ahead and looked through your codebase and made a few changes:

Fixes and Improvements

1. Removed node_modules in the smart_contract directory
2. removed duplicated code that would run twice in setDrug
3. I've added additional checks to prevent empty values/invalid values from input data that could lead to unexpected issues and bugs
4. I've implemented the buying function to actually trade funds between the buyer and seller based off the quantity

Overall, great job and have a nice rest of your week!

Hello @Emma360, great job on your submission. I've went through your codebase and found a few minor issues. The changes I've made are:

Fixes and Improvement

1. Removed node modules in smartcontract directory
2. Refactored app.js using the prettier extension
3. Added comments in smart contract to improve documentation of code
4. Renamed variables and functions for better documentation
5. Changed if statements into asserts statements for checks
6. I've noticed that you had a blocktimestamp variable that you were not using, so I've added a duration parameter when booking to allow users to book an event according to a certain time
7. I've also noticed that the admin variable was never used, so I fixed that by changing the owner variable into customer and initialized the admin as the owner of the event, I've made the necessary changes wherever the owner variable was used as well
8. Added the functionality for the event owner/admin to end the booking after duration have been over,
9. Added the functionality for the event owner to pause and unpause booking
10. I moved up the functions making changes to an instance of Event into the model.ts file for best practices

Goodluck and have a nice weekend ahead.

Hello @agtmaurice, great job on your project. I've gone ahead and looked through your smart contract's files and didn't notice any bugs/issues. However, I've implemented a few small improvements:

Fixes and Improvements

1. Added checks for the input data when creating a picture to prevent unexpected behaviors and issues on the frontend
2. Added check when changing the price to make sure that the picture was still up for sale.

Overall, great job and have a nice rest of your week!

Hello @frank_lin, great job on your project. I've gone ahead and looked through your codebase and didn't find any issues/bugs. However, I've gone ahead and made some minor improvements:

Improvements

1. Cleaned up logging logs
2. I've added checks for the item object when creating/buying a movie poster to prevent empty/invalid values from the input data
3. I've modified the check for accountIds to be more secure (used number eight instead of one as accountIds on testnet ends with ".testnet" which is in length 8)
4. I've modified the logic of removing the poster when calling the selling function to instead find the index, store it, break the for loop, and finally slice and remove the poster. This makes the function slightly faster and more gas efficient in most scenarios

Overall great job and have a nice rest of your week!

Hello @chigozie, great job on your project. I've gone ahead and tested your dapp and found 2 issues:

Fixes and Improvements

1. Added checks for a task's description and name to not be initialized as empty
2. Added checks and the variable owner to make sure only the owner of a task can update and delete a task as previously everyone could do that which was a security risk.

Good luck and have a nice week ahead!

Hello mrray, great job on finishing the challenge and the course. I've went ahead and looked through your smartcontract and found a few issues/bugs:

1. Removed the isTrader unordered mapping as it wasn't used for anything
2. Refactored and merged the methods of both the trader and item models to save up on gas as the separate functions were being used for the same thing (e.g saving rate and adding the sender to the rated array)
3. I've gone ahead and added checks for the inputs when adding an item to the platform to prevent empty values that could cause unexpected behaviors/issues
4. I've added additional checks when buying an item to prevent the item's owner to buy his item
5. I've also added a check for the traderId in rateTrader to be a valid accountId
6. Lastly, I've added the functionality to resell an item

Good luck and have a nice week ahead!

Hello @rdbhagat999, great job on your project. I've gone ahead and looked through your smart contract files and made a few improvements as I've didn't notice any bugs or issues:

Improvements

1. Cleaned up logging logs
2. I've added checks for the item object when creating/buying a movie poster to prevent empty/invalid values from the input data
3. I've modified the check for accountIds to be more secure(used number eight instead of one as accountIds on testnet ends with ".testnet" which is in length 8)
4. I've modified the logic of removing the poster when calling the selling function to instead find the index, store it, break the for loop, and finally slice and remove the poster. This makes the function slightly faster and more gas efficient in most scenarios

Good luck and have a nice rest of your week!

Hello @Favourdgreat, great job on your project. I've went ahead and looked through your smart contract and implemented a few cool changes that would improve your project:

Fixes and Improvements

1. You didn't have the asconfig.json file which were causing the compilation of the smart contract to fail
2. I've noticed that you had many variables that you were not using, so I've went ahead and created new functionalities around them
3. I've went ahead and implemented functions to allow users to put an item on sale or on rent with a price argument for price/rentPrice depending on which function you would call
4. I've went ahead and added additional checks when creating an item to prevent unexpected bugs and issues
5. I've also added new functions that let users to buy an item on sale or rent an item available for rent based off a duration for the renting period
6. Finally I've also added a function that lets the item's owner/renter to end their rent on an item
7. I've also moved the code that made changes to an item in sell Item function into an inherited method of the class Item
8. Improved documentation of code by adding comments in the Nat spec format

Good luck and have a nice rest of your week

Hello @nunu, great job on your project. I've went ahead and looked through your smart contract and found a few issues/bugs.

Fixes and Improvements

1. Improved documentation of code by adding comments using the Nat spec format
2. Removed disliked as it was redundant but could also cause bugs/unexpected behaviors
3. I've went ahead and created a new mapping to keep track of a user's likes. This tackles, the issue of users being able to like and dislikes as many times as they wish. Furtheremore, I've removed the need to change owners every time someone likes/dislikes as this seem to be an unexpected behavior
4. I've went ahead and added a check when adding a new secret to make sure that the secret's text isn't not empty to prevent unexpected bugs and issues
5. Modified the logic of liking and disliking a secret to make the necessary state changes to the smart contract
6. I've went ahead and added a check to prevent amount to be at least greater than u128.min and also a check to prevent the owner of the secret to gift himself. Finally, I've added a variable giftAmount to keep track of the total amount donated to a secret's owners
7. Moved the logic of making changes to a Secret to be an inherited method of the model for best practices

Good luck and have a nice weekend.

Hey @Jack144, great job on your project. I've gone ahead and looked through your codebase and made a few improvements:

Improvements

1. Improved documentation of code by adding useful checks to describe the functionalities of each function
2. Added additional checks to prevent unexpected behaviors and issues

Overall great job and have a nice week ahead!

Hello @princeibs, great job on your project. I've went ahead and noticed a few issues with your project:

Fixes and Improvements

1. Simplified the logic of liking/disliking to save up on gas fees
2. Added checks when creating a blog to make sure that import values are not empty strings
3. Simplified the logic of returning allblogs by using .values() instead of a for loop. Removed the slug vector as it was only used for that
4. the near-api-js wasn't included in the package.json file in the root directory which was preventing the server from starting
5. Some minor fixes on the frontend around uncontrolled components and key prop for blogs data
6. I've added the method donate and the variable donations to keep track of the amount donated in buyCoffee
7. There is currently an issue with the keyStore value where you cannot use change methods (unfortunately I'm sure what could be causing that) as it is undefined
8. I've also noticed an issue when logging out in /write or when logging in from /welcome, users would be stuck onto the same page(though sometimes it works properly)

Good luck and have a nice rest of your week.