/**
* Paid API Example
*
* A cryptocurrency data API that accepts x402 payments.
*
* @author Universal Crypto MCP
* @license Apache-2.0
*/
import express, { Request, Response } from "express";
// In production, import from @nirholas/x402-deploy
// import { wrapExpressWithX402 } from "@nirholas/x402-deploy/express";
const app = express();
app.use(express.json());
// =============================================================================
// Free Endpoints
// =============================================================================
app.get("/api/health", (_req: Request, res: Response) => {
res.json({
status: "healthy",
version: "1.0.0",
timestamp: new Date().toISOString(),
});
});
// =============================================================================
// Basic Paid Endpoints ($0.0001 each)
// =============================================================================
app.get("/api/v1/price/:symbol", async (req: Request, res: Response) => {
try {
const symbol = req.params.symbol.toLowerCase();
const response = await fetch(
`https://api.coingecko.com/api/v3/simple/price?ids=${symbol}&vs_currencies=usd&include_24hr_change=true&include_market_cap=true&include_24h_vol=true`
);
if (!response.ok) {
res.status(502).json({ error: "Failed to fetch price data" });
return;
}
const data = await response.json();
if (!data[symbol]) {
res.status(404).json({ error: `Symbol ${symbol} not found. Use CoinGecko IDs (bitcoin, ethereum, solana, etc.)` });
return;
}
res.json({
symbol: symbol.toUpperCase(),
price: data[symbol].usd,
change24h: data[symbol].usd_24h_change || 0,
marketCap: data[symbol].usd_market_cap || 0,
volume24h: data[symbol].usd_24h_vol || 0,
timestamp: Date.now(),
});
} catch (error) {
res.status(500).json({ error: "Internal server error" });
}
});
app.get("/api/v1/prices", async (_req: Request, res: Response) => {
try {
const coins = "bitcoin,ethereum,solana,arbitrum,polygon";
const response = await fetch(
`https://api.coingecko.com/api/v3/simple/price?ids=${coins}&vs_currencies=usd&include_24hr_change=true`
);
if (!response.ok) {
res.status(502).json({ error: "Failed to fetch price data" });
return;
}
const data = await response.json();
const prices = Object.entries(data).map(([id, info]: [string, any]) => ({
symbol: id.toUpperCase(),
price: info.usd,
change24h: info.usd_24h_change || 0,
}));
res.json({
prices,
timestamp: Date.now(),
});
} catch (error) {
res.status(500).json({ error: "Internal server error" });
}
});
app.get("/api/v1/trending", async (_req: Request, res: Response) => {
try {
const response = await fetch("https://api.coingecko.com/api/v3/search/trending");
if (!response.ok) {
res.status(502).json({ error: "Failed to fetch trending data" });
return;
}
const data = await response.json();
const trending = data.coins.slice(0, 10).map((item: any, index: number) => {
const coin = item.item;
return {
rank: index + 1,
symbol: coin.symbol,
name: coin.name,
change24h: coin.data?.price_change_percentage_24h?.usd || 0,
marketCapRank: coin.market_cap_rank,
};
});
res.json({
trending,
timestamp: Date.now(),
});
} catch (error) {
res.status(500).json({ error: "Internal server error" });
}
});
// =============================================================================
// Premium Endpoints ($0.01+ each)
// =============================================================================
app.get("/api/v1/premium/analysis/:symbol", async (req: Request, res: Response) => {
try {
const symbol = req.params.symbol.toLowerCase();
// Fetch current price and market data
const priceResponse = await fetch(
`https://api.coingecko.com/api/v3/coins/${symbol}?localization=false&tickers=false&community_data=true&developer_data=false`
);
if (!priceResponse.ok) {
res.status(404).json({ error: `Symbol ${symbol} not found` });
return;
}
const coinData = await priceResponse.json();
const marketData = coinData.market_data;
const currentPrice = marketData.current_price.usd;
// Calculate technical indicators from real data
const high24h = marketData.high_24h.usd;
const low24h = marketData.low_24h.usd;
const change24h = marketData.price_change_percentage_24h;
const change7d = marketData.price_change_percentage_7d;
const change30d = marketData.price_change_percentage_30d;
// Determine trend based on real price movements
const trend = (change7d > 0 && change30d > 0) ? "bullish" :
(change7d < 0 && change30d < 0) ? "bearish" : "neutral";
// Calculate support and resistance from real data
const support = [
low24h * 0.98,
marketData.atl.usd * 1.1,
currentPrice * 0.95,
].sort((a, b) => b - a);
const resistance = [
high24h * 1.02,
marketData.ath.usd * 0.9,
currentPrice * 1.05,
].sort((a, b) => a - b);
const analysis = {
symbol: symbol.toUpperCase(),
name: coinData.name,
timestamp: Date.now(),
technical: {
trend,
currentPrice,
high24h,
low24h,
support: support.map(p => parseFloat(p.toFixed(2))),
resistance: resistance.map(p => parseFloat(p.toFixed(2))),
priceChange24h: change24h,
priceChange7d: change7d,
priceChange30d: change30d,
},
sentiment: {
overall: coinData.sentiment_votes_up_percentage > 60 ? "bullish" :
coinData.sentiment_votes_up_percentage < 40 ? "bearish" : "neutral",
bullishVotes: coinData.sentiment_votes_up_percentage,
bearishVotes: coinData.sentiment_votes_down_percentage,
communityScore: marketData.community_score,
developerScore: marketData.developer_score,
},
market: {
marketCap: marketData.market_cap.usd,
marketCapRank: coinData.market_cap_rank,
volume24h: marketData.total_volume.usd,
circulatingSupply: marketData.circulating_supply,
totalSupply: marketData.total_supply,
athPrice: marketData.ath.usd,
athDate: marketData.ath_date.usd,
atlPrice: marketData.atl.usd,
atlDate: marketData.atl_date.usd,
},
recommendation: {
action: trend === "bullish" ? "buy" : trend === "bearish" ? "sell" : "hold",
confidence: Math.abs(change7d) > 10 ? 0.8 : 0.5,
reason: `${trend} trend detected. 7d change: ${change7d.toFixed(2)}%, 30d change: ${change30d.toFixed(2)}%`,
},
};
res.json(analysis);
} catch (error) {
res.status(500).json({ error: "Internal server error" });
}
});
app.get("/api/v1/premium/signals", async (_req: Request, res: Response) => {
try {
// Fetch real market data for top coins
const coins = ["bitcoin", "ethereum", "solana"];
const response = await fetch(
`https://api.coingecko.com/api/v3/coins/markets?vs_currency=usd&ids=${coins.join(",")}&order=market_cap_desc&sparkline=false&price_change_percentage=24h,7d`
);
if (!response.ok) {
res.status(502).json({ error: "Failed to fetch market data" });
return;
}
const data = await response.json();
// Generate signals based on real price movements
const signals = data.map((coin: any) => {
const change24h = coin.price_change_percentage_24h || 0;
const change7d = coin.price_change_percentage_7d_in_currency || 0;
const currentPrice = coin.current_price;
const high24h = coin.high_24h;
const low24h = coin.low_24h;
// Determine signal type based on real momentum
let type: "buy" | "sell" | "hold";
let reason: string;
let confidence: number;
if (change24h > 5 && change7d > 10) {
type = "buy";
reason = `Strong upward momentum: +${change24h.toFixed(1)}% (24h), +${change7d.toFixed(1)}% (7d)`;
confidence = Math.min(0.85, 0.5 + change24h / 20);
} else if (change24h < -5 && change7d < -10) {
type = "sell";
reason = `Downward pressure: ${change24h.toFixed(1)}% (24h), ${change7d.toFixed(1)}% (7d)`;
confidence = Math.min(0.85, 0.5 + Math.abs(change24h) / 20);
} else {
type = "hold";
reason = `Consolidating: ${change24h >= 0 ? "+" : ""}${change24h.toFixed(1)}% (24h). Waiting for clear direction.`;
confidence = 0.5;
}
// Calculate technical levels from real data
const range = high24h - low24h;
const stopLoss = type === "sell" ? high24h * 1.02 : low24h * 0.95;
const target = type === "buy" ? currentPrice * 1.1 : currentPrice * 0.9;
return {
symbol: coin.symbol.toUpperCase(),
name: coin.name,
type,
currentPrice,
entry: type === "hold" ? null : currentPrice,
target: parseFloat(target.toFixed(2)),
stopLoss: parseFloat(stopLoss.toFixed(2)),
confidence: parseFloat(confidence.toFixed(2)),
timeframe: "4h",
reason,
priceChange24h: change24h,
priceChange7d: change7d,
high24h,
low24h,
marketCap: coin.market_cap,
volume24h: coin.total_volume,
};
});
res.json({
signals,
generatedAt: Date.now(),
validFor: "4 hours",
disclaimer: "This is algorithmic analysis based on price momentum. Not financial advice. Always do your own research.",
});
} catch (error) {
res.status(500).json({ error: "Internal server error" });
}
});
// =============================================================================
// Start Server
// =============================================================================
const PORT = process.env.PORT || 3000;
// In production, wrap with x402:
// import config from "./x402.config.json";
// const wrappedApp = wrapExpressWithX402(app, config);
// wrappedApp.listen(PORT, ...);
// For demo, run without x402 wrapper
app.listen(PORT, () => {
console.log(`✅ Paid API running on http://localhost:${PORT}`);
console.log("");
console.log("📍 Endpoints:");
console.log(" FREE: GET /api/health");
console.log(" $0.0001: GET /api/v1/price/:symbol");
console.log(" $0.0005: GET /api/v1/prices");
console.log(" $0.0001: GET /api/v1/trending");
console.log(" $0.01: GET /api/v1/premium/analysis/:symbol");
console.log(" $0.05: GET /api/v1/premium/signals");
console.log("");
console.log("💡 To enable x402 payments, uncomment the wrapExpressWithX402 code");
});
