Files
endlessh-go/client.go
2021-10-26 21:56:39 -07:00

106 lines
3.1 KiB
Go

// Copyright (C) 2021 Shizun Ge
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
//
package main
import (
"math/rand"
"net"
"sync/atomic"
"time"
"github.com/golang/glog"
"github.com/prometheus/client_golang/prometheus"
)
var letterBytes = []byte(" abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890!@#$%^&*()-=_+[]{}|;:',./<>?")
func randStringBytes(n int64) []byte {
b := make([]byte, n+1)
for i := range b {
b[i] = letterBytes[rand.Intn(len(letterBytes))]
}
b[n] = '\n'
return b
}
type client struct {
conn net.Conn
last time.Time
next time.Time
start time.Time
interval time.Duration
geoipSupplier string
geohash string
country string
location string
bytes_sent int
}
func NewClient(conn net.Conn, interval time.Duration, maxClient int64, geoipSupplier string) *client {
addr := conn.RemoteAddr().(*net.TCPAddr)
atomic.AddInt64(&numCurrentClients, 1)
atomic.AddInt64(&numTotalClients, 1)
geohash, country, location, err := geohashAndLocation(addr.IP.String(), geoipSupplier)
if err != nil {
glog.Warningf("Failed to obatin the geohash of %v: %v.", addr.IP, err)
}
clientIP.With(prometheus.Labels{
"ip": addr.IP.String(),
"geohash": geohash,
"country": country,
"location": location}).Inc()
glog.V(1).Infof("ACCEPT host=%v port=%v n=%v/%v\n", addr.IP, addr.Port, numCurrentClients, maxClient)
return &client{
conn: conn,
last: time.Now(),
next: time.Now().Add(interval),
start: time.Now(),
interval: interval,
geohash: geohash,
country: country,
location: location,
bytes_sent: 0,
}
}
func (c *client) Send(bannerMaxLength int64) error {
defer func(c *client) {
addr := c.conn.RemoteAddr().(*net.TCPAddr)
millisecondsSpent := time.Now().Sub(c.last).Milliseconds()
c.last = time.Now()
c.next = time.Now().Add(c.interval)
atomic.AddInt64(&numTotalMilliseconds, millisecondsSpent)
clientSeconds.With(prometheus.Labels{"ip": addr.IP.String()}).Add(float64(millisecondsSpent) / 1000)
}(c)
length := rand.Int63n(bannerMaxLength)
bytes_sent, err := c.conn.Write(randStringBytes(length))
if err != nil {
return err
}
c.bytes_sent += bytes_sent
atomic.AddInt64(&numTotalBytes, int64(bytes_sent))
return nil
}
func (c *client) Close() {
addr := c.conn.RemoteAddr().(*net.TCPAddr)
atomic.AddInt64(&numCurrentClients, -1)
atomic.AddInt64(&numTotalClientsClosed, 1)
glog.V(1).Infof("CLOSE host=%v port=%v time=%v bytes=%v\n", addr.IP, addr.Port, time.Now().Sub(c.start).Seconds(), c.bytes_sent)
c.conn.Close()
}