James Challenge

The challenge was to implement an application through which a big bank can easily issue new loans and find out what the value and volume of outstanding debt are.

Instalation instructions

• Install SQLite (for example in Ubuntu run sudo apt-get update and then sudo apt-get install sqlite3 libsqlite3-dev)
• Clone this repo
• Create a virtual environment and activate it
• Change directory to the project, cd james-challenge/james
• Upgrade packaging tools running pip install --upgrade pip setuptools
• Install the project in editable mode with its testing requirements running pip install -e ".[testing]"

Running the application

To run the project in Development mode:

• Change directory to the project, cd james-challenge/james
• Create the database running initialize_james_db development.ini
• Run the application with pserve development.ini

The application is set to run at http://0.0.0.0:8080. To access the API's endpoints the user must add an authorization key to the header of his request, with its value being a hexidecimal representation of the SHA256 encoding of the API key. In Development the API key is seekrit and its encoded value is c3d09a8c8b5d4ee86daa9d7926cccff543b55cb71bd0dfdc8ef5b2eff096f449.

To run the project in Production mode:

• Set the following environment variables:
  • SQLALCHEMY_URL with the database connection string
  • AUTH_SECRET with a string representing the authentication secret of the application
  • API_KEY with a string representing the API key
• Create the database running initialize_james_db production.ini
• Run the application with pserve production.ini

Also in Production it would be advisable to run the application using HTTPS, which can be done by replacing the default waitress server by, for example, gunicorn (with the right configuration, of course), or by using nginx as a reverse proxy that would handle HTTPS and pass HTTP to the application.

API Enpoints

Please refer to https://gist.github.com/sergio2540/59d668fe820a06b1eebc42419cef3ef2.

In Development the URLs are http://0.0.0.0:8080/loans, http://0.0.0.0:8080/loans/<:id>/payments and http://0.0.0.0:8080/loans/<:id>/balance.

Comments:

• Payment's amount must be equal to the Loan's installment
• There can be only one payment per month