Public APIs

A collection of useful public utility APIs built with Go and chi.

Getting Started

# Install dependencies
go mod download

# Start development server
go run ./cmd/server

# Build
go build -o server ./cmd/server

The server starts at http://localhost:3000.

Environment Variables

Variable Default Description
AUTH_ENABLED — Set to true or 1 to require authentication
AUTH_TOKEN — Bearer token required when auth is enabled
BROWSER_WS ws://127.0.0.1:9222 Chrome DevTools WebSocket endpoint for headless browser
BROWSER_WS_ENABLED — Set to true or 1 to use headless browser; falls back to plain fetch otherwise
STORAGE_PATH files Directory for uploaded files
OCR_TOKEN — PaddleOCR API authentication token

Docker

# Start Lightpanda headless browser
docker compose -f compose.dev.yaml up -d

# Build and run
docker build -t public-apis .
docker run -p 3000:3000 --env-file .env public-apis

API Reference

QR Code

Generate QR Code

GET /qr/generate?c=<content>

Generates a QR code as an SVG image.

Query Parameters:

Param Type Description
c string Content to encode

Response: image/svg+xml

Scan QR Code

POST /qr/scan

Decodes a QR code from an uploaded image file.

Request: multipart/form-data

Response: application/json

HTML to Markdown

Convert HTML to Markdown

GET /html/to-markdown?url=<url>

Fetches a URL using a headless browser (via rod), strips CSS/JS, and converts the rendered HTML content to Markdown with a YAML frontmatter block containing page metadata.

Image to ASCII

Convert Image to ASCII Art

GET /img-to-ascii/convert?url=<url>&maxSize=<maxSize>

Fetches a remote image and converts it to ASCII art.

URL Proxy

Fetch a URL

GET /proxy?url=<url>

Fetches the target URL through the headless browser (see BROWSER_WS/BROWSER_WS_ENABLED) and returns the raw response body (HTML, XML, etc.) along with the upstream status code and content type.

Query Parameters:

Param Type Description
url string Absolute http/https URL to fetch

Response: The upstream status code, Content-Type, and raw body.

Requires the headless browser to be enabled (BROWSER_WS_ENABLED=true); otherwise the request fails with 502 Bad Gateway. Targets resolving to private, loopback, link-local, or multicast addresses are rejected with 502 Bad Gateway.

MCP Server

This project exposes an MCP (Model Context Protocol) server using the SSE transport.

The MCP endpoint is available at http://localhost:3000/mcp/sse.

Tools

File Upload

Upload Page

GET /upload

A web interface for uploading files with drag-and-drop support.

Upload File

POST /upload/file

Upload a file. Requires authentication.

Download File

GET /upload/file/{name}

Download a previously uploaded file by name.

Tech Stack