Dropper Backend

This is the backend application for the Dropper frontend. It handles file uploads to a Google Cloud Storage (GCS) bucket.

Features

• Uploading files to the cloud storage (GCS)
• Displaying metadata about stored and received objects
• Sharing files in the store via email or private/public links
• Previewing supported file types (image, video, audio, pdf)
• Adding notes attached to stored files

Prerequisites

• Go installed on your system.
• Docker and Docker Compose for containerization.
• A Google Cloud project with a GCS bucket and appropriate credentials.

Getting Started

Clone the Repository

git clone https://github.com/tscrond/dropper.git
cd dropper

Set Up Environment Variables

Create a .env file in the root directory and add the following variables:

.env:

#!/bin/bash

DROPPER_LISTEN_PORT=3000
GCS_BUCKET_NAME="dropper-app"
GOOGLE_APPLICATION_CREDENTIALS=<redacted>

GOOGLE_PROJECT_ID=<redacted>
GOOGLE_COOKIE_SECRET=<redacted>
GOOGLE_CLIENT_ID=<redacted>
GOOGLE_CLIENT_SECRET=<redacted>

# for SES email provider
AWS_ACCESS_KEY_ID=<redacted>
AWS_SECRET_ACCESS_KEY=<redacted>
AWS_REGION=<redacted>

# for "standard" email provider
SMTP_HOST=<redacted>
SMTP_PORT="587"
SMTP_USERNAME=<redacted>
SMTP_PASSWORD=<redacted>

POSTGRES_USER="devuser"
POSTGRES_PASSWORD="devpass" 
POSTGRES_DB="devdb"
DB_HOST="localhost"

FRONTEND_ENDPOINT="http://localhost:5173"
BACKEND_ENDPOINT="http://localhost:3000"

.envs:

#!/bin/bash

CURRENT_IP="localhost"

export DROPPER_LISTEN_PORT=3000
export GCS_BUCKET_NAME="dropper-app"
export GOOGLE_APPLICATION_CREDENTIALS=<redacted>

export GOOGLE_PROJECT_ID=<redacted>
export GOOGLE_COOKIE_SECRET=<redacted>
export GOOGLE_CLIENT_ID=<redacted>
export GOOGLE_CLIENT_SECRET=<redacted>

# for SES email provider
export AWS_ACCESS_KEY_ID=<redacted>
export AWS_SECRET_ACCESS_KEY=<redacted>
export AWS_REGION=<redacted>

# for "standard" email provider
export SMTP_HOST=<redacted>
export SMTP_PORT="587"
export SMTP_USERNAME=<redacted>
export SMTP_PASSWORD=<redacted>

export POSTGRES_USER="devuser"
export POSTGRES_PASSWORD="devpass" 
export POSTGRES_DB="devdb"
export DB_HOST="localhost"

export FRONTEND_ENDPOINT="http://${CURRENT_IP}:5173"
export BACKEND_ENDPOINT="http://${CURRENT_IP}:3000"

Build and Run with Docker

docker-compose up --build

This will build the Docker image and start the backend service.

API Endpoints

🔐 Authentication Endpoints

Method	Endpoint	Description
ANY	/auth/callback	Callback endpoint for OAuth authentication. Handles the redirect after a user successfully logs in via the OAuth provider.
ANY	/auth/oauth	Initiates the OAuth login flow. Redirects the user to the OAuth provider's authentication page.
ANY	/auth/is_valid	Validates the current session or token to confirm if the user is authenticated.
ANY	/auth/logout	Logs the user out by clearing session data or revoking tokens.

📁 File Handling Endpoints

Method	Endpoint	Description
POST	/files/upload	Authenticated. Uploads a file to the user's cloud storage (likely GCS).
POST	/files/share	Authenticated. Shares a file with another user.
GET	/files/received	Authenticated. Retrieves files that have been shared with the current user.

📥 Download Endpoints

Method	Endpoint	Description
GET	/d/private/{token}	Authenticated. Allows users to download their private files via a secure token.
GET	/d/{token}	Public. Proxy for downloading shared files using a token (possibly with time-limited access).

👤 User Info Endpoints

Method	Endpoint	Description
GET	/user/data	Authenticated. Returns profile or account details of the current user.
GET	/user/bucket	Authenticated. Provides details about the user’s GCS bucket (e.g., usage, files, etc.).
POST	/user/private/download_token	Authenticated. Generates a download token for a private file (used with /d/private/{token}).

Project Structure

• cmd/: Entry point of the application.
• internal/: Internal packages for business logic.
• pkg/: Shared packages across the application.
• Dockerfile: Docker configuration for the backend service.
• docker-compose.yaml: Docker Compose configuration for multi-container setup.

License

This project is licensed under the MIT License.