Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/al-ghaly/ruleengineusingscala

A Rule-Based discount calculating engine for a retail store. The engine reads transaction data, applies various discount rules based on the product, date, and other criteria, and writes the results back to a database.
https://github.com/al-ghaly/ruleengineusingscala

database etl etl-automation functional-programming jdbc oracle programming scala

Last synced: about 1 month ago
JSON representation

A Rule-Based discount calculating engine for a retail store. The engine reads transaction data, applies various discount rules based on the product, date, and other criteria, and writes the results back to a database.

Awesome Lists containing this project

README 

        
# Scala ETL Rule Engine



## Project Overview



This project is a Scala-based ETL (Extract, Transform, Load) application designed as a rule-based discount calculating engine for a large retail company. The engine reads transaction data from a CSV file, processes each transaction according to predefined rules to calculate discounts, and loads the processed data into an Oracle database for further analysis and reporting.



### Project Requirements



1. **Qualifying Rules and Calculation:**

   - Discounts based on product expiry, with a tiered discount system depending on how close the product is to its expiration date.

   - Special discounts for cheese and wine products.

   - A 50% discount for products sold on the 23rd of March.

   - Quantity-based discounts, encouraging bulk purchases.

   - Additional discounts for transactions made through the app and payments made using Visa cards.



2. **Technical Considerations:**

   - All core logic must be written in a pure functional manner:

     - Use only `vals`, no `vars`.

     - Avoid mutable data structures.

     - Exclude loops; instead, use recursion or higher-order functions.

     - Ensure all functions are pure; they should not produce side effects.

   - The application logs events in a specific format and writes them to `rules_engine.log`.



3. **Logging Format:**

   ```

   TIMESTAMP     LOGLEVEL      MESSAGE

   ```



4. **Technical Specifications:**

   - Scala and a JVM-compatible environment for execution.

   - Oracle Database for data persistence.

   - Proper error handling and logging of operations.



## Technology Stack



- **Scala** for the backend logic.

- **Oracle Database** for storing processed transactions.

- **SBT** for project build and dependency management.



## Features



- **Dynamic Discount Calculation:** Applies various discounts based on product expiry, sales category (cheese, wine), special sale dates, quantity, application usage, and Visa payments.

- **Functional Programming:** Adheres strictly to functional programming principles with immutable data structures and pure functions, ensuring predictable and side-effect-free operations.

- **Comprehensive Logging:** Logs detailed operational data to a file, which helps in monitoring and troubleshooting the application.



## Flow Chart



The following flow chart visualizes the sequence of operations from data input to processing and output:



![FlowChart](https://github.com/al-ghaly/RuleEngineUsingScala/assets/61648960/492e9da6-7cae-4729-bb95-abaaeacef2cc)



## Technical Details



### Code Structure



- **Transaction Processing**: Each transaction is parsed and processed through various discount rules.

- **Discount Qualification**: Discounts are determined based on set rules, including product type, expiry, special dates, and quantity thresholds.

- **Database Operations**: After calculating discounts, the transaction data, along with computed discounts, are stored in a database.

- **Logging**: Events and errors are logged in a file, following a specific format that includes a timestamp, log level, and message.



### Key Components



- **Transaction Classes**: Define the structure for transaction data and processed transaction data.

- **Rule Functions**: A set of functions that determine the eligibility for discounts based on different criteria.

- **Data Handling**: Functions to read from and write to CSV files and the Oracle database.

- **Logger Utility**: A utility to handle logging across the system uniformly.



### Core Functionality



- **Read Data:** The engine starts by reading transaction data from a CSV file. Each transaction includes details such as the timestamp of the sale, product name, expiry date, quantity sold, and payment method.



- **Apply Discount Rules:** Based on the transaction details, the engine applies several discount rules:

  - **Product Expiry:** Discounts are offered based on how soon a product is expiring.

  - **Product Type:** Special discounts for specific products like cheese and wine.

  - **Special Dates:** A substantial discount is applied to all products sold on the 23rd of March.

  - **Quantity Discounts:** Discounts increase with the quantity of the product purchased.

  - **App Usage:** Encourages use of the store's app by applying discounts based on the transaction channel.

  - **Payment Method:** Promotes the use of Visa cards by providing a discount for transactions using Visa.



- **Calculate Final Price:** After applying the relevant discounts, the engine calculates the final price for each transaction.



- **Write Results:** The processed transactions, along with the discounts applied and the final calculated prices, are then written to a database for persistence.



- **Logging:** Throughout its operation, the engine logs various events such as the start and end of data processing, errors, and other significant occurrences in the system.



## Getting Started



### Prerequisites



- Scala 2.12.x

- Java 8+

- SBT (Scala Build Tool)

- Oracle Database or another relational database with JDBC support



### Setup and Installation



1. **Clone the repository**:

   ```sh

   git clone 

   ```

2. **Navigate to the project directory**:

   ```sh

   cd 

   ```

3. **Compile the project using SBT**:

   ```sh

   sbt compile

   ```



### Running the Application



Run the application using SBT:

```sh

sbt run

```



## Configuration



- **Database Connection**: Set up the database connection parameters in the application to point to your Oracle database instance.

- **CSV File Path**: Ensure the path to the CSV file containing transaction data is correctly set in the application.



## Acknowledgements



This project was developed as part of the ITI 44 curriculum, leveraging functional programming techniques to solve practical problems in retail operations.



---