Group Assignment (16%)

Introduction

The objectives of this assignment are to gain practical experience in interacting with a relational database management system using an Application Programming Interface (API) (Python DB-API). This assignment additionally provides an opportunity to use more advanced features of a database such as functions.

This is a group assignment for teams of about 3 members, and it is assumed that you will continue in your Assignment 1 group. You should inform the unit coordinator as soon as possible if you wish to change groups.

Please also keep an eye on your email and any announcements that maybe made on Ed.

Submission Details

The final submission of your database application is due at 11:59pm on Sunday 22th October (Week 11). You should submit the items for submission (detailed below) via Canvas.

Items for submission

Please submit your solution to Assignment 2 in the ’Assignment’ section of the unit’s Canvas site by the deadline, including EXACTLY THREE files:

•    An assignment coversheet as a PDF document (.pdf file suffix) which is available for download fromthis linkon Canvas.

•    A SQL file (RACASchema.sql) containing the SQL statements necessary to generate the database schema and sample data. This must contain the original schema and insert SQL statements, and any new records and stored procedures you may have added.

•    A Python file (database.py) containing the Python code you have written to access the database.

Task 1: The Rent-A-Car Australia (RACA) System

In this assignment, you will be working with the RACA system which is currently under development. The system still requires work in numerous areas, including interaction with the database. Your main task in this assignment is to handle requests for reads and writes to the database coming from the user interface (UI). We first describe the main features that the RACA system should include from a UI perspective, and then discuss where the majority of your database code needs to be implemented.

Logging In

The first form a user is presented with, when starting the RACA system is the Login, as shown in Figure 1. This feature is still under development and currently requires that an employee enters their username and password to be validated prior to being successfully logged in to the system. Security features such as password encryption/hashing will be implemented at a later stage (and is out of scope for this assignment). Once logged in, the user is taken to the cars list page to view their associated hire cars.

Figure 1 – Login form

Viewing Cars List

Once a user is logged in, they are shown a list of all their associated hire cars, as shown below in Figure 2. This list must be ordered such that the most recently purchased cars appear at the bottom. The list is also sorted by description in ascending order, and status in descending order. Each car has a make, model, status, type, wheel, purchase date, managing employee, and description. A car is associated with an employee if the employee is allocated as the person in charge of managing all aspects related to the hire car.

Figure 2 – Viewing Cars List

Finding Cars

A user can search through all hire cars by entering a word or phrase (a ‘keyword’) in the field next to the

Find button, as shown in Figure 3, and then clicking on Find. When such a keyword is specified, then the

retrieved cars and shown on the list are those that include this word or phrase in the make, model, status,   car type, wheel system, managing employee’s full name, or description. The search is case insensitive. For example, given the search keyword ‘new’, Find will return all cars that include the keyword ‘new’ in the make, model, status, car type, wheel system, managing employee’s full name, or description. Searching with a blank/empty keyword field will show all of the logged in user’s associated cars. Any search results returned must be ordered such that hire cars without a managing employee would appear at the top, and then by purchase date in ascending order. The search results must exclude those cars whose purchase  dates are older than 15 years (from today’s date).

Figure 3 – Finding Cars

Adding a Car

Users may also add a new hire car by clicking on the Add Cartabin the title bar. They may enter car details such as make, model, type, wheel system, purchase date, and description, in the popup dialog. Once the popup dialog appears, click on Add Car button, as shown in Figure 4. A new car has a default status of “New Stock” and will not be assigned to an employee to manage.

Figure 4 – Adding a Car

Updating a Car

Users can also update a car by modifying data in the car details screen as shown in Figure 5, and clicking on Update Car button. You can access this update screen by clicking on a car from the list of cars in the Cars tab.

Figure 5 – Updating a Car

Database Interaction Code

The files that are needed for the Python version of assignment areas follows:

1.    RACASchema.sql: a file which contains SQL statements you need to run to create and initialise

the RACA system database, before starting the application

https://canvas.sydney.edu.au/files/33303631/download?download_frd=1

2.    Assignment2_PythonSkeleton.zip: a zip file encapsulating the Python project for the RACA systemhttps://canvas.sydney.edu.au/files/33381402/download?download_frd=1

To inspect the RACA system code, you need to unzip the ZIP archive first, which will create a folder that    includes the name Assignment2_PythonSkeleton. If you experience any difficulties installing and exploring the project, ask your tutor or lecturer for assistance.

The skeleton code uses a number of Python modules to implement a simple browser-based GUI for the RACA system. The main modules are the Flask framework for the GUI and the psycopg2 module for the PostgreSQL database access. Similar to tutorial 6, you will need to install the Psycopg2 module and the Flask module. The skeleton code follows the structure described below:

•  The main program starts in the main.py file. You need to use the correct username/password details as specified in tutorial 6, and then implement the missing database access functions – including any necessary SQL code statements required – in the data layer database.py.

•  The presentation layer is done via a simple HTML interface that can be accessed from a web browser.

The corresponding page templates are located in the templates/ subdirectory, their CSS style file is static/css.

•  The transition between the different GUI pages and the initialisation of the Flask framework is done in the  routes.py file.  It  currently just  invokes  the  pages,  but there  is  no further  business  logic implemented yet.

You can run the code by running “python main.py”.  This starts a local web server and prints out some debug messages in the terminal; the GUI can then be accessed with any web browser on the same computer via   the   local    URL  http://127.0.0.1:5000/  (If   that   doesn’t   work  you    can   also   try http://0.0.0.0:5000/). Please note that, to terminate the application, you will need to stop the local web server which is running in the background.

Task 2: Functions Implementation

Core Functionality

In this assignment, you are provided with a Python skeleton project that must serve as the starting point for your assignment. Your task is to provide a complete implementation for the file database.py, as well as make any modifications necessary to the database schema (i.e., RACASchema.sql). Specifically, you need to modify and complete these five functions:

1. checkEmployeeCredentials (for login)

2. findCarsByEmployee (for viewing cars list)

3. findCarsByCriteria (for finding cars)

4.addCar (for adding car)

5.updateCar (for updating car)

Note that, for each function, the corresponding action and outcome should be implemented by issuing SQL queries to the database management system. If you directly output the result set, pre-process, manipulate and/or make changes to the input or output datasets using Python code i.e. without issuing SQL queries, you are considered as cheating, and you will get penalised or zero point for the assignment. No additional Python modules or libraries should be imported.

Marking

This assignment is worth 16% of your final grade for the unit of study. Your group’s submission will be marked inline with the rubric that follows.

Group member participation

If members of your group do not contribute sufficiently, you should alert the unit coordinator as soon as possible. The course instructor has the discretion to scale the group’s mark for each member as follows: