解决Go中拦截HTTP流数据时字段丢失的问题

proxy.ModifyResponse = func(response *http.Response) error {
    go func() {
        buf := make([]byte, 4096) // 定义一个足够大的缓冲区
        for {
            n, err := response.Body.Read(buf)
            if n > 0 {
                buffer.Write(buf[:n])
                if _, writeErr := writer.Write(buf[:n]); writeErr != nil {
                    log.Println("Error writing to pipe:", writeErr)
                    return
                }
            }
            if err != nil {
                if err != io.EOF {
                    log.Println("Error reading from response body:", err)
                }
                break
            }
        }
    }()
    return nil
}

// 创建一个io.Pipe用于拦截和转发数据
reader, writer := io.Pipe()
var buffer bytes.Buffer
var mu sync.Mutex
var wg sync.WaitGroup

proxy.ModifyResponse = func(response *http.Response) error {
    log.Println("ModifyResponse started")
    wg.Add(1)
    go func() {
        defer wg.Done()
        defer func(writer *io.PipeWriter) {
            err := writer.Close()
            if err != nil {
                log.Println("Error closing pipe writer:", err)
            }
        }(writer)

        buf := make([]byte, 4096) // 定义一个足够大的缓冲区
        for {
            n, err := response.Body.Read(buf)
            if n > 0 {
                mu.Lock()
                buffer.Write(buf[:n])
                if _, writeErr := writer.Write(buf[:n]); writeErr != nil {
                    log.Println("Error writing to pipe:", writeErr)
                    mu.Unlock()
                    return
                }
                mu.Unlock()
            }
            if err != nil {
                if err != io.EOF {
                    log.Println("Error reading from response body:", err)
                }
                break
            }
        }
    }()
    return nil
}

// 使用Goroutine将代理服务器的数据流转发给客户端
wg.Add(1)
go func() {
    defer wg.Done()
    log.Println("Copying to client started")
    if _, err := io.Copy(c.Writer, reader); err != nil {
        log.Println("Error copying to client:", err)
        return
    }
}()

// 实际发送请求到目标服务器
proxy.ServeHTTP(c.Writer, c.Request)

// 等待所有的Goroutine完成
wg.Wait()
log.Println("All Goroutines finished")

// 在这里将完整的数据保存到数据库
completeData := buffer.String()
log.Println("Complete data:", completeData)