📞 Call Logs Converter

Welcome to my Call Logs Converter demo project!

This application converts call logs in PDF format into CSV format, showcasing advanced Java and Spring ecosystem skills. It provides a robust and scalable solution with an intuitive API, offering three main endpoints for users to upload PDFs, check conversion status, and download the converted CSVs.

📑 Endpoints

1. Upload PDF Call Logs

• Endpoint: /api/call-logs/
• Method: POST
• Description: Upload a PDF call logs to be converted into CSV format.
• Request Body: form-data with a key named file and the PDF as the value.
• Response: the callLogId to track the conversion status.

2. Check Conversion Status

• Endpoint: /api/call-logs/{callLogId}/status
• Method: GET
• Description: Check the conversion status of the uploaded call logs. Status can be COMPLETED or FAILED.
• Response: indicating the conversion status.

3. Download Converted CSV

• Endpoint: /api/call-logs/{callLogId}/download
• Method: GET
• Description: Retrieve the converted call logs in CSV format.
• Response: the CSV file as a byte stream

⚙️ Workflow

1. Upload PDF: Upload a PDF call log via /api/call-logs/, the server processes the file asynchronously.
2. Conversion Status: Check the status of the conversion by querying /api/call-logs/{callLogId}/status.
3. Download CSV: Retrieve the converted CSV file from /api/call-logs/{callLogId}/download after conversion.

💻 Skills and Technologies

Core Technologies

• Java 21: Utilizes new features such as Pattern Matching for instanceof, Record and Sequenced Collections.
• Spring Boot: Framework for building production-ready applications.
• Spring WebFlux & Reactor: Enables asynchronous and non-blocking communication using reactive programming paradigms.
• Maven Wrapper: Ensures consistent Maven versions across different environments for managing the project.

Architecture

• Hexagonal Architecture: Organizes the code using the ports and adapters pattern to separate concerns and improve testability and maintainability.
• Asynchronous Processing with SSE: Utilizes Server-Sent Events (SSE) to notify users about the conversion status in real-time by leveraging asynchronous communication.

Reactive Components

• Mono and Flux: Represents asynchronous sequences in the application.
• Sinks, Schedulers, and Operators: Utilized for handling and transforming streams of data.
• Spring Functional Endpoints: Implements routes using RouterFunction for a more functional style.

Testing and Quality Assurance

Comprehensive integration and unit tests ensure the reliability and correctness of the application. The project uses the following tools to achieve test coverage and maintain code quality:

• JUnit 5: Framework for writing and running tests.
• Mockito: Mocks dependencies for unit testing.
• Hamcrest: Provides matchers for writing readable assertions.
• spring-test & reactor-test: Enhances testing capabilities for Spring and Reactor applications.

Logging

• SLF4J: Logging facade to ensure consistent logging throughout the application.

Dependencies

• Apache PDFBox: Used for parsing and extracting content from PDF files.
• Apache Commons CSV: Facilitates CSV file creation and manipulation.

📦 Usage

To build and run the project using the Maven Wrapper, follow these steps:

1. Build the project:

   ./mvnw clean install

2. Run the application:

   ./mvnw spring-boot:run

🌟 Conclusion

This project demonstrates advanced knowledge and practical skills in modern Java development, reactive programming with Spring WebFlux, and a strong emphasis on testing and architecture. It's designed to be scalable, maintainable and efficient.

Feel free to contact me with any questions or contributions!

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Author: Loïc FAVRELIERE
LinkedIn: linkedin.com/in/loic-favreliere