minio/pkg/api/quota/conn_limit.go
2015-06-06 18:11:38 -07:00

90 lines
2.1 KiB
Go

/*
* Minimalist Object Storage, (C) 2015 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package quota
import (
"net"
"net/http"
"sync"
"github.com/minio/minio/pkg/utils/log"
)
// requestLimitHandler
type connLimit struct {
sync.RWMutex
handler http.Handler
connections map[uint32]int
limit int
}
func (c *connLimit) IsLimitExceeded(ip uint32) bool {
if c.connections[ip] >= c.limit {
return true
}
return false
}
func (c *connLimit) GetUsed(ip uint32) int {
return c.connections[ip]
}
func (c *connLimit) Add(ip uint32) {
c.Lock()
defer c.Unlock()
count := c.connections[ip]
count = count + 1
c.connections[ip] = count
return
}
func (c *connLimit) Remove(ip uint32) {
c.Lock()
defer c.Unlock()
count, _ := c.connections[ip]
count = count - 1
if count <= 0 {
delete(c.connections, ip)
return
}
c.connections[ip] = count
}
// ServeHTTP is an http.Handler ServeHTTP method
func (c *connLimit) ServeHTTP(w http.ResponseWriter, req *http.Request) {
host, _, _ := net.SplitHostPort(req.RemoteAddr)
longIP := longIP{net.ParseIP(host)}.IptoUint32()
if c.IsLimitExceeded(longIP) {
hosts, _ := net.LookupAddr(uint32ToIP(longIP).String())
log.Debug.Printf("Connection limit reached - Host: %s, Total Connections: %d\n", hosts, c.GetUsed(longIP))
writeErrorResponse(w, req, ConnectionLimitExceeded, req.URL.Path)
return
}
c.Add(longIP)
defer c.Remove(longIP)
c.handler.ServeHTTP(w, req)
}
// ConnectionLimit limits the number of concurrent connections
func ConnectionLimit(h http.Handler, limit int) http.Handler {
return &connLimit{
handler: h,
connections: make(map[uint32]int),
limit: limit,
}
}