File Converter Application

Problem Statement

Converting files between formats usually means installing desktop software or juggling several single-purpose websites. Users wanted one simple place to upload a file, pick a target format, and download the result without worrying about where their files ended up.

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Project Objective

Build a full-stack file converter that could:

• Accept file uploads from the browser.
• Convert files into a range of target formats.
• Store source and converted files securely.
• Show users the progress and status of each conversion.
• Let users download converted files easily.

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Solution Summary

Created a full-stack application with a React and Redux frontend and a Node.js / Express.js backend. Users upload a file, choose an output format, and the backend runs the conversion and returns a download link.

Uploaded and converted files are stored in AWS S3, keeping the API server stateless and file storage durable.

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Key Features

• Drag-and-drop uploads with file type and size checks.
• Format selection based on the uploaded file type.
• Conversion status tracking in the UI.
• Download links for converted files.
• AWS S3 storage for source and output files.
• Clear error messages for unsupported or failed conversions.

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Individual Contribution

• Built the React frontend and the Redux store for upload and conversion state.
• Implemented the upload flow with client-side validation.
• Developed Express.js endpoints for upload, conversion, and download.
• Integrated conversion logic on the Node.js backend.
• Set up AWS S3 storage for incoming and converted files.
• Handled errors and edge cases across the full upload-to-download flow.

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Challenges & Solutions

Challenges

• Handling large files without overloading the server.
• Keeping the UI in sync with long-running conversions.
• Supporting many input and output format combinations.
• Storing files safely and cleaning them up.

Solutions

• Streamed files to and from AWS S3 instead of holding them in memory.
• Tracked conversion state in Redux and updated the UI as jobs progressed.
• Mapped each input type to its supported output formats.
• Organized files in S3 by job so they were easy to manage and remove.

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Outcomes

• A single, simple workflow for uploading, converting, and downloading files.
• A stateless backend that relies on S3 for storage.
• Clear feedback to users at each step of the process.

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Architecture & Scalability

Architecture Summary

A React single-page application using Redux for state, talking to a Node.js / Express.js REST API. The API handles uploads, runs conversions, and reads and writes files in AWS S3.

Scalability Improvements

• Stateless API layer that can be scaled horizontally.
• Cloud object storage for all files.
• Format support organized so new conversions can be added easily.