Function createTestServer

test/network/large-file.test.js:25–75

(port)

// Create a local HTTP server that serves files of specified sizes
// No rate limiting - relies on VM's built-in network rate limiting
function createTestServer(port) {
    return new Promise((resolve, reject) => {
        const server = http.createServer((req, res) => {
            // Parse URL to get requested size: /bytes/<size>
            const match = req.url.match(/^\/bytes\/(\d+)$/);
            if (!match) {
                res.writeHead(404);
                res.end('Not Found');
                return;
            }
            
            const size = parseInt(match[1], 10);
            console.log(`  [Server] Serving ${(size / 1024 / 1024).toFixed(2)}MB`);
            
            res.writeHead(200, {
                'Content-Type': 'application/octet-stream',
                'Content-Length': size,
                'Connection': 'close'
            });
            
            // Stream data in chunks, but as fast as TCP allows (no artificial rate limiting)
            const CHUNK_SIZE = 64 * 1024;  // 64KB chunks
            let remaining = size;
            
            function sendChunk() {
                while (remaining > 0) {
                    const toWrite = Math.min(CHUNK_SIZE, remaining);
                    const chunk = crypto.randomBytes(toWrite);
                    remaining -= toWrite;
                    
                    if (!res.write(chunk)) {
                        // TCP backpressure - wait for drain
                        res.once('drain', sendChunk);
                        return;
                    }
                }
                res.end();
                console.log(`  [Server] Finished sending ${size} bytes`);
            }
            
            sendChunk();
        });
        
        server.listen(port, '127.0.0.1', () => {
            console.log(`  [Server] Test server listening on http://127.0.0.1:${port}`);
            resolve(server);
        });
        
        server.on('error', reject);
    });
}

async function test() {
    console.log("=== Very Large File Download Tests ===\n");