fileO

fileO is a simple cloud storage backend built with FastAPI that supports uploading, listing, and deleting files (images, videos, documents). It can run in Local Mode (your laptop) or Cloud Mode (AWS Lambda + S3 + DynamoDB + API Gateway).

Architecture

Modes

Local Mode

Runs FastAPI on your machine.

• Files are uploaded to AWS S3
• Metadata is written to DynamoDB
• The server runs normally using Uvicorn

Start locally:

uvicorn main:app --reload

Cloud Mode

Refer to Cloud Setup

Runs inside AWS Lambda using Mangum.

• Triggered by API Gateway
• Same endpoints, same behavior
• No server or VM needed

API Endpoints

GET /

Health check.

POST /login

Authenticates the user.

Body:

• email
• password

Returns:

• JWT token

GET /me

Checks token and returns logged-in user.

Header:

Authorization: Bearer <token>

POST /upload

Generates S3 presigned URLs to upload files directly from the browser.

Body:

• List of files (name + MIME type)

Returns:

• Presigned S3 URLs
• S3 keys stored in DynamoDB

GET /photos

Returns all files uploaded by the user.

Header:

Authorization: Bearer <token>

Each item includes:

• docId
• s3Key
• fileType
• mimeType
• uploadedAt

DELETE /delete/{docId}

Deletes the file from S3 and DynamoDB.

Header:

Authorization: Bearer <token>

.env Configuration

Required for BOTH Local Mode & Cloud Mode

BUCKET_NAME=your-s3-bucket
DDB_TABLE=your-dynamodb-table

JWT_SECRET=your-secret-key
TOKEN_EXPIRE_MINUTES=43200

AWS_REGION=ap-south-1

Only for Local Mode (when you run on your machine)

AWS_ACCESS_KEY_ID=your-local-access-key
AWS_SECRET_ACCESS_KEY=your-local-secret-key

(Cloud Mode uses IAM Role instead — no keys needed.)

AWS Setup (Cloud Mode)

1. Create an S3 Bucket

• Use bucket name from .env
• No public access required (presigned URLs work privately)

2. Create DynamoDB Table

Table name = DDB_TABLE.

Keys:

• Partition Key → userId (String)
• Sort Key → uploadedat (Number)

3. Deploy to AWS Lambda

• Zip your project and dependencies
• Upload to Lambda
• Set environment variables from .env (without AWS keys)
• Add API Gateway → HTTP API

4. Give Lambda permission to use S3 + DynamoDB

IAM role must include:

• AmazonS3FullAccess
• AmazonDynamoDBFullAccess

(or custom minimal role)

Local Mode Setup

1. Install dependencies:

pip install -r requirements.txt

2. Create .env file with AWS keys included.

3. Run FastAPI server:

uvicorn main:app --reload

4. Access:

http://localhost:8000

Cloud Mode Setup

1. Remove AWS keys from .env
2. Deploy Lambda + API Gateway
3. Set environment variables
4. Access the cloud API URL:

https://<api-id>.execute-api.ap-south-1.amazonaws.com

Frontend Setup

Set the API base URL based on mode:

Local Mode:

const API_BASE = "http://localhost:8000";

Cloud Mode:

const API_BASE = "https://<api-id>.execute-api.ap-south-1.amazonaws.com";