Proxy IP Implementation for Golang Crawl: Golang Configuration for Proxy IP Crawl

What to do when a crawler hits an anti-crawler? Try this.

What's the biggest headache for everyone writing crawlers? Nine out of ten will say that the IP is blocked, right? This time you need to proxy IP to help. Let's not talk about false today, hand in hand to teach you to use Golang with proxy IP, focusing on how to use good!ipipgoThe service to stay alive.

Core Principles of Configuration Agents

Golang's http.Client actually hides a transportation captain - the Transport object. To change away from proxies, you need to do something with this transportation captain. Remember the core formula:

transport := &http.Transport{
    Proxy: http.ProxyURL(Proxy address),
}
client := &http.Client{Transport: transport}

The trick is that the Proxy attribute receives a function that, before each request, goes and asks, "Which way this time?" ProxyURL is an out-of-the-box function that takes care of fixed proxies. If you use a dynamic proxy pool, you'll have to write your own polling logic.

Real-world code with comments

For example, suppose we start withipipgoGot an HTTP proxy: 112.95.161.201:8008 with an account password exclusive to vip users. The code has to be written like this:

func main() {
    // Proxy address assembly
    proxyUrl, _ := url.Parse("http://user:pass@112.95.161.201:8008")

    // Create customized transports
    transport := &http.Transport{
        Proxy: http.ProxyURL(proxyUrl),
        TLSClientConfig: &tls.Config{InsecureSkipVerify: true}, // skip certificate verification
    }

    // Assemble the ultimate client
    client := &http.
        Transport: transport, }
        Timeout: 15 time.
    }

    // Initiating a live request
    resp, err := client.Get("https://目标网站.com")
    if err ! = nil {
        log.Fatal("Request failed:", err)
    }
    defer resp.Body.Close()

    // Process the response data...
}

Watch out for that.TLSClientConfigSome sites may have problems with their SSL certificates, so adding this will prevent handshake failures. However, it is not recommended to skip authentication on regular websites, and this is just a demonstration of its usage.

How Dynamic Proxy Pools Play

Single agents are easily recognized, you have to rotate them with a pool of agents. In conjunction withipipgoAPIs that can be messed with like this:

var proxyPool = []string{
    "http://user:pass@112.95.161.201:8008",
    "http://user:pass@112.95.162.105:8012".
    //... Other proxies
}

func getRandomProxy() func(http.Request) (url.URL, error) {
    rand.Seed(time.Now().UnixNano())
    return func(_ http.Request) (url.URL, error) {
        return url.Parse(proxyPool[rand.Intn(len(proxyPool))])
    }
}

// Replace the Proxy setting when used
transport.Proxy = getRandomProxy()

This randomly selects a proxy for each request, reducing the probability of being blocked.ipipgos agent pool is updated frequently, it is recommended to pull the latest agent list from their API every 5 minutes.

Common pitfalls QA

Q: What should I do if the agent suddenly doesn't work?

A: First check the proxy availability, it is recommended to use theipipgos health check interface. Their agent comes with failover, which is less of a hassle than building your own

Q: Why are requests slowing down?

A: You may encounter a high latency proxy. Suggestions: ① choose a node close to the geographic location ② set a reasonable timeout ③ use ipipgo's intelligent routing service

Q: HTTPS website can't catch data?

A: Check the certificate settings and add a root certificate if necessary. If you are using a self-signed certificate, remember to configure the correct TLS parameters in the Transport.

Why ipipgo?

Tested with his service, the crawler survival rate from 37% to 89%, especially the need for long-term operation of the project, no longer need to get up in the middle of the night to change the agent.

Advanced Tips: Automatic Switching

Put a fuse on the crawler and automatically change the proxy when it encounters continuous failure:

type RetryClient struct {
    client http.
    Retries int
Client retries int }

func (rc RetryClient) Get(url string) (http.Response, error) {
    Get(url string) (http.Response, error) { for i := 0; i < rc.retries; i++ {
        resp, err := rc.client.Get(url)
        if err == nil && resp.StatusCode == 200 {
            return resp, nil
        }
        // Trigger a proxy switch
        rc.client.Transport.(http.Transport).Proxy = getRandomProxy()
    }
    return nil, fmt.Errorf("Maximum number of retries exceeded")
}

This self-healing mechanism works in conjunction withipipgoThe massive IP pool can basically realize unattended operation around the clock.

Finally, a word of caution, the choice of agent services have to look at the long-term stability. Previously used a few cheap, the beginning of the okay, behind a variety of moths. Change to theipipgoAfter saving a lot of heartache, there is a professional operation and maintenance team is not the same, especially suitable for commercial projects that require stability.