The Bricklane website allows customers to open an account and purchase shares in one or more funds. Before a customer can buy shares, they top up their account with a desired amount, using a debit card.
The website is supported by an underlying investment platform, consisting of modules that each perform a specific role. Each module is a separate package, installed on the platform as a dependency. One of these modules is tasked with processing an incoming payments CSV file, then generating a share order CSV, consumed by another module.
This report contains the customer_id and the number of shares their payment(s) will purchase, given the share price.
customer_id,shares
123,100
987,3400
For development, the module can be invoked with a local runner script, which simulates how it is integrated with the investment platform. From the src/ directory, run:
python -m bricklane_platform.local_runner <path_to_payments_csv> <source> <share_price>
To see example output:
python -m bricklane_platform.local_runner ../card_payments_example.csv card 1.20
Some customers have indicated they would prefer to top up their account by making a bank transfer, rather than using their debit card.
Update the bricklane_platform.services.PaymentProcessor class to support both card and bank transfer payments. We will receive a separate CSV file from our payment provider, in a similar format to card payments:
customer_id,date,amount,bank_account_id
789,2018-10-25,900,20
345,2018-11-03,900,60
Unlike card payments, our payment provider will only update us once a bank transfer has been successfully processed.
Remember, the module is installed on the platform as a dependency, therefore the API to both the PaymentProcessor and ShareEngine service classes must not change.
You can check your implementation by using the example CSV:
python -m bricklane_platform.local_runner ../bank_payments_example.csv bank 1.20
This should produce the result:
customer_id,shares
789,735
345,735
You can run the tests from the root of the project with:
python -m unittest discover
If you would like to run a specific test, specify the path as the second argument:
python -m unittest tests.bricklane_platform.models.test_payment
The code base has been written in Python 2.7 for compatibility reasons. There are no dependencies, although assumes the dateutils package is installed.