作为一个资深golang研发工程师用代码写一个广告拦截工具不用hosts方法不用web服务

作为一个资深的Golang研发工程师，我可以为您提供一个使用Golang编写的广告拦截工具的示例代码。该示例代码使用了DNS解析和HTTP代理技术来拦截广告。

package main

import (
	"fmt"
	"net"
	"net/http"
	"net/url"
	"strings"
	"sync"
)

// AdvertisementInterceptor is a custom HTTP transport that intercepts and blocks advertisements
type AdvertisementInterceptor struct {
	lock sync.Mutex
	dns  map[string]net.IP
}

// RoundTrip implements the http.RoundTripper interface
func (ai *AdvertisementInterceptor) RoundTrip(req *http.Request) (*http.Response, error) {
	// Check if the request is for a known advertisement domain
	if ai.isAdvertisement(req.URL.Host) {
		// Return a custom response for advertisements
		return &http.Response{
			StatusCode: http.StatusForbidden,
			Body:       http.NoBody,
		}, nil
	}

	// Make the actual HTTP request
	resp, err := http.DefaultTransport.RoundTrip(req)
	if err != nil {
		return nil, err
	}

	return resp, nil
}

// isAdvertisement checks if a given domain is a known advertisement domain
func (ai *AdvertisementInterceptor) isAdvertisement(domain string) bool {
	ai.lock.Lock()
	defer ai.lock.Unlock()

	ip, ok := ai.dns[domain]
	if !ok {
		// Perform DNS lookup if the IP is not already known
		ips, err := net.LookupIP(domain)
		if err != nil {
			return false
		}

		if len(ips) > 0 {
			ip = ips[0]
			ai.dns[domain] = ip
		}
	}

	// Check if the IP is a known advertisement IP address
	// You can add more advertisement IP addresses here
	adIPs := []string{"127.0.0.1", "::1"}
	for _, adIP := range adIPs {
		if ip.String() == adIP {
			return true
		}
	}

	return false
}

func main() {
	// Initialize the AdvertisementInterceptor
	ai := &AdvertisementInterceptor{
		dns: make(map[string]net.IP),
	}

	// Configure the HTTP client to use the AdvertisementInterceptor
	httpClient := &http.Client{
		Transport: ai,
	}

	// Make a sample HTTP request
	resp, err := httpClient.Get("https://example.com")
	if err != nil {
		fmt.Println("Error:", err)
		return
	}

	// Print the response status code
	fmt.Println("Status Code:", resp.StatusCode)
}

请注意，此示例代码仅用于演示目的，实际使用中可能需要更复杂的逻辑来检测和拦截广告