Refactor and improve documentation, add examples
This commit is contained in:
JY Tan
200
examples/01-dev-server/app.js
Normal file
200
examples/01-dev-server/app.js
Normal file
@@ -0,0 +1,200 @@
|
||||
/**
|
||||
* Demo Express app that:
|
||||
* 1. Serves an API on port 3000
|
||||
* 2. Connects to Redis on localhost:6379
|
||||
* 3. Attempts to call external APIs (blocked by fence)
|
||||
*
|
||||
* This demonstrates allowLocalOutbound - the app can reach
|
||||
* local services (Redis) but not the external internet.
|
||||
*/
|
||||
|
||||
import express from "express";
|
||||
import Redis from "ioredis";
|
||||
import { ProxyAgent, fetch as undiciFetch } from "undici";
|
||||
|
||||
const app = express();
|
||||
const PORT = 3000;
|
||||
|
||||
// Connect to Redis on localhost
|
||||
const redis = new Redis({
|
||||
host: "127.0.0.1",
|
||||
port: 6379,
|
||||
connectTimeout: 3000,
|
||||
retryStrategy: () => null, // Don't retry, fail fast for demo
|
||||
});
|
||||
|
||||
let redisConnected = false;
|
||||
|
||||
redis.on("connect", () => {
|
||||
redisConnected = true;
|
||||
console.log("[app] Connected to Redis");
|
||||
|
||||
// Seed some demo data
|
||||
redis.set(
|
||||
"user:1",
|
||||
JSON.stringify({ id: 1, name: "Alice", email: "alice@example.com" })
|
||||
);
|
||||
redis.set(
|
||||
"user:2",
|
||||
JSON.stringify({ id: 2, name: "Bob", email: "bob@example.com" })
|
||||
);
|
||||
redis.set(
|
||||
"user:3",
|
||||
JSON.stringify({ id: 3, name: "Charlie", email: "charlie@example.com" })
|
||||
);
|
||||
console.log("[app] Seeded demo data");
|
||||
});
|
||||
|
||||
redis.on("error", (err) => {
|
||||
if (!redisConnected) {
|
||||
console.log("[app] Redis connection failed:", err.message);
|
||||
}
|
||||
});
|
||||
|
||||
// Helper: Make external API call using undici with proxy support
|
||||
// Node.js native https doesn't respect HTTP_PROXY, so we use undici
|
||||
async function fetchExternal(url) {
|
||||
const proxyUrl = process.env.HTTPS_PROXY || process.env.HTTP_PROXY;
|
||||
|
||||
const options = {
|
||||
signal: AbortSignal.timeout(5000),
|
||||
};
|
||||
|
||||
// Use proxy if available (set by fence)
|
||||
if (proxyUrl) {
|
||||
options.dispatcher = new ProxyAgent(proxyUrl);
|
||||
}
|
||||
|
||||
const response = await undiciFetch(url, options);
|
||||
const text = await response.text();
|
||||
|
||||
return {
|
||||
status: response.status,
|
||||
data: text.slice(0, 200),
|
||||
};
|
||||
}
|
||||
|
||||
// Routes
|
||||
|
||||
app.get("/", (req, res) => {
|
||||
res.json({
|
||||
message: "Dev Server Demo",
|
||||
redis: redisConnected ? "connected" : "disconnected",
|
||||
endpoints: {
|
||||
"/api/users": "List all users from Redis",
|
||||
"/api/users/:id": "Get user by ID from Redis",
|
||||
"/api/health": "Health check",
|
||||
"/api/external": "Try to call external API (blocked by fence)",
|
||||
},
|
||||
});
|
||||
});
|
||||
|
||||
app.get("/api/users", async (req, res) => {
|
||||
if (!redisConnected) {
|
||||
return res.status(503).json({
|
||||
error: "Redis not connected",
|
||||
hint: "Start Redis: docker run -p 6379:6379 redis:alpine",
|
||||
});
|
||||
}
|
||||
|
||||
try {
|
||||
const keys = await redis.keys("user:*");
|
||||
const users = await Promise.all(
|
||||
keys.map(async (key) => JSON.parse(await redis.get(key)))
|
||||
);
|
||||
res.json({
|
||||
source: "redis",
|
||||
count: users.length,
|
||||
data: users,
|
||||
});
|
||||
} catch (error) {
|
||||
res.status(500).json({ error: error.message });
|
||||
}
|
||||
});
|
||||
|
||||
app.get("/api/users/:id", async (req, res) => {
|
||||
if (!redisConnected) {
|
||||
return res.status(503).json({
|
||||
error: "Redis not connected",
|
||||
hint: "Start Redis: docker run -p 6379:6379 redis:alpine",
|
||||
});
|
||||
}
|
||||
|
||||
try {
|
||||
const user = await redis.get(`user:${req.params.id}`);
|
||||
if (user) {
|
||||
res.json({ source: "redis", data: JSON.parse(user) });
|
||||
} else {
|
||||
res.status(404).json({ error: "User not found" });
|
||||
}
|
||||
} catch (error) {
|
||||
res.status(500).json({ error: error.message });
|
||||
}
|
||||
});
|
||||
|
||||
app.get("/api/health", async (req, res) => {
|
||||
if (!redisConnected) {
|
||||
return res.status(503).json({
|
||||
status: "unhealthy",
|
||||
redis: "disconnected",
|
||||
});
|
||||
}
|
||||
|
||||
try {
|
||||
await redis.ping();
|
||||
res.json({
|
||||
status: "healthy",
|
||||
redis: "connected",
|
||||
});
|
||||
} catch (error) {
|
||||
res.status(503).json({
|
||||
status: "unhealthy",
|
||||
redis: "error",
|
||||
error: error.message,
|
||||
});
|
||||
}
|
||||
});
|
||||
|
||||
app.get("/api/external", async (req, res) => {
|
||||
console.log("[app] Attempting external API call...");
|
||||
|
||||
try {
|
||||
const result = await fetchExternal("https://httpbin.org/get");
|
||||
// Check if we're using a proxy (indicates fence is running)
|
||||
const usingProxy = !!(process.env.HTTPS_PROXY || process.env.HTTP_PROXY);
|
||||
res.json({
|
||||
status: "success",
|
||||
message: usingProxy
|
||||
? "✓ Request allowed (httpbin.org is whitelisted)"
|
||||
: "⚠️ No proxy detected - not running in fence",
|
||||
proxy: usingProxy ? process.env.HTTPS_PROXY : null,
|
||||
data: result,
|
||||
});
|
||||
} catch (error) {
|
||||
res.json({
|
||||
status: "blocked",
|
||||
message: "✓ External call blocked by fence",
|
||||
error: error.message,
|
||||
});
|
||||
}
|
||||
});
|
||||
|
||||
// Startup
|
||||
|
||||
app.listen(PORT, () => {
|
||||
console.log(`
|
||||
╔═══════════════════════════════════════════════════════════╗
|
||||
║ Dev Server Demo ║
|
||||
╠═══════════════════════════════════════════════════════════╣
|
||||
║ Server: http://localhost:${PORT} ║
|
||||
║ Redis: localhost:6379 ║
|
||||
╠═══════════════════════════════════════════════════════════╣
|
||||
║ Endpoints: ║
|
||||
║ GET / - API info ║
|
||||
║ GET /api/users - List users from Redis ║
|
||||
║ GET /api/users/:id - Get user by ID ║
|
||||
║ GET /api/health - Health check ║
|
||||
║ GET /api/external - Try external call (blocked) ║
|
||||
╚═══════════════════════════════════════════════════════════╝
|
||||
`);
|
||||
});
|
||||
Reference in New Issue
Block a user