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Mohammad Waseem
Mohammad Waseem

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Overcoming IP Bans During High-Traffic Web Scraping with TypeScript

Overcoming IP Bans During High-Traffic Web Scraping with TypeScript

Web scraping is an essential technique for data collection, but during high traffic events—such as sales, breaking news, or product launches—scrapers often face IP bans. These bans are typically implemented to prevent server overloads or abuse, but they severely impact data acquisition workflows. In this guide, we’ll explore strategies to mitigate IP bans using TypeScript, focusing on ethical and resilient scraping techniques suitable for large-scale operations.

Understanding the Challenge

When scraping at scale, servers monitor incoming requests for suspicious patterns such as high request frequency from a single IP. To protect resources, they may block IP addresses temporarily or permanently. This can be particularly problematic during high-traffic periods, where the volume of requests spikes.

Common mitigation strategies include:

  • Rotating IP addresses
  • Using proxies
  • Randomizing request patterns
  • Detecting and responding to bans dynamically

In this article, we will combine these tactics with TypeScript for flexibility and performance.

Strategy 1: Implement IP Rotation with Proxy Pools

The first step is to avoid hitting the server with requests from a single IP. Using a pool of proxies, we rotate IP addresses for each request. Here's a simple implementation:

import axios from 'axios';

// List of proxy URLs
const proxies = [
    'http://proxy1.example.com:8080',
    'http://proxy2.example.com:8080',
    'http://proxy3.example.com:8080'
];

function getRandomProxy() {
    return proxies[Math.floor(Math.random() * proxies.length)];
}

async function fetchWithProxy(url: string) {
    const proxy = getRandomProxy();
    try {
        const response = await axios.get(url, {
            proxy: {
                host: proxy.split(':')[1].replace('//', ''),
                port: parseInt(proxy.split(':')[2])
            },
            headers: {
                'User-Agent': 'Mozilla/5.0 (compatible; MyScraper/1.0)'
            },
            timeout: 10000
        });
        return response.data;
    } catch (error) {
        console.error(`Request via ${proxy} failed:`, error.message);
    }
}
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This script randomly selects a proxy for each request, reducing the likelihood of IP-based bans.

Strategy 2: Detect Bans and Adjust Behavior Dynamically

Detecting when your IP is banned requires inspecting server responses. Many servers respond with status codes like 403 or 429. Upon detecting such responses, the scraper should adjust its behavior—pause, switch proxies, or slow down.

async function robustFetch(url: string): Promise<void> {
    let proxyIndex = 0;
    while (proxyIndex < proxies.length) {
        const proxy = proxies[proxyIndex];
        try {
            const response = await axios.get(url, {
                proxy: {
                    host: proxy.split(':')[1].replace('//', ''),
                    port: parseInt(proxy.split(':')[2])
                },
                headers: {
                    'User-Agent': 'Mozilla/5.0 (compatible; MyScraper/1.0)'
                },
                timeout: 10000
            });
            if (response.status === 200) {
                console.log('Successful fetch');
                // Process response.data
                break;
            }
        } catch (error) {
            if (error.response && (error.response.status === 403 || error.response.status === 429)) {
                console.log(`Banned with proxy ${proxy}, switching...`);
                proxyIndex++;
                await new Promise(res => setTimeout(res, 3000)); // Wait before switching
            } else {
                console.error(`Request failed: ${error.message}`);
            }
        }
    }
}
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This dynamic response detection helps the scraper adapt in real-time, minimizing downtime.

Strategy 3: Randomize Request Timing and Patterns

Uniform request patterns aid server detection of automation. Introducing randomized delays and request rates can mimic human behavior:

function delay(minMs: number, maxMs: number): Promise<void> {
    const timeout = Math.random() * (maxMs - minMs) + minMs;
    return new Promise(res => setTimeout(res, timeout));
}

async function scrapeLoop(urls: string[]) {
    for (const url of urls) {
        await delay(1000, 3000); // Random delay between 1-3 seconds
        await robustFetch(url); // Use the dynamic fetch
    }
}
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This randomness frustrates pattern-based detection mechanisms.

Ethical Considerations

While technical solutions can reduce ban incidences, ethical scraping practices should be prioritized. Always respect robots.txt, implement rate limiting aligned with server policies, and seek permission from data owners where possible.

Conclusion

Mitigating IP bans during high-traffic scraping involves a layered approach: rotating proxies, dynamic response handling, and behavior randomization. Implemented effectively in TypeScript, these strategies enable resilient, scalable, and responsible data acquisition even during demanding scenarios.

By combining these technical techniques with ethical considerations, developers can build sustainable scraping workflows that respect server resources while achieving their data collection objectives.


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