CS350 Fundamentals of Computing Systems - Assignment 2 - Bank Transactions
Assignment 2 - Bank Transactions
Due Date: Fri, 9 Feb, 2024
Please make sure to regularly commit and push your work to Gitlab so that we can see your progress. Final submission will be on Gradescope – this will be the only source of truth for grading.
There will be no late submission and no extensions, so make sure to submit on time.
Introduction
Correctness of data is very important in real world applications such as banking. An ideal bank should be able to handle millions of requests for various accounts simultaneously, whilst ensuring that all user data is correct.
Some common tasks that all banking applications have to handle are:
- Create account
- Deposit funds
- Withdraw funds
- Transfer funds
In this assignment, you are given a codebase with some parts of a banking application implemented. Some parts of the code are not implemented and some might be buggy. Your task is to implement the missing code, and fix any possible bugs in the code.
Code Overview and Objectives
All code for this assignment resides in bank.go
You are provided with the following structs for defining a bank and accounts within it:
type Bank struct {
bankLock *sync.RWMutex
accounts map[int]*Account
}
type Account struct {
balance int
lock *sync.Mutex
}You need to ensure that the following methods are implemented correctly:
- CreateAccount()
- Deposit()
- Withdraw()
- Transfer()
- [BONUS!] DepositAndCompare()
Your code’s execution should be deterministic. The tester will make a huge number of concurrent calls to your code, and running the exact same input multiple times should not affect the final state of the Bank or any of the Accounts within it.
Your code should also be able to handle errors such as handling account ids that dont exist or are being duplicated by throwing an error. In such cases, your code needs to log appropriate error messages.
DPrintf
We also provide you with a function called DPrintf(). It is similar to Printf, but you can set
const Debug = falseto disable the DPrintf() statements, which may help you debug your code.
It is set to true by default. Using DPrintf is optional, but recommended for ease of coding.
Instructions
- Clone the repository and navigate to the bank directory.
- Put your code in the appropriate methods/files.
- Run the tests
- go test -v -race
- You should ensure that you the entire test suite works multiple times, ie. try running the tests at least 5 times successfully.
- Upload the bank.go file to Gradescope. Do not change the file name, or the autograder may not recognize it.
Your output should be something like this
go test -v -race
=== RUN TestCreateAccountBasic
--- PASS: TestCreateAccountBasic (0.00s)
=== RUN TestCreateAccountMany
--- PASS: TestCreateAccountMany (0.00s)
=== RUN TestManyDepositsAndWithdraws
--- PASS: TestManyDepositsAndWithdraws (3.57s)
=== RUN TestFewTransfers
--- PASS: TestFewTransfers (0.00s)
=== RUN TestManyTransfers
--- PASS: TestManyTransfers (0.00s)
=== RUN TestDepositAndCompare
--- PASS: TestDepositAndCompare (0.01s)
PASS
ok cs350/bank-transactions 4.771s
