Files
cgrates/utils/concureqs.go
2020-10-29 17:55:26 +01:00

121 lines
3.0 KiB
Go

/*
Real-time Online/Offline Charging System (OCS) for Telecom & ISP environments
Copyright (C) ITsysCOM GmbH
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 <http://www.gnu.org/licenses/>
*/
package utils
import (
"net"
"net/rpc"
"net/rpc/jsonrpc"
)
var ConReqs *ConcReqs
var AnalizerWraperFunc = func(conn rpc.ServerCodec, enc string, from, to net.Addr) rpc.ServerCodec {
return conn
}
type ConcReqs struct {
limit int
strategy string
aReqs chan struct{}
}
func NewConReqs(reqs int, strategy string) *ConcReqs {
cR := &ConcReqs{
limit: reqs,
strategy: strategy,
aReqs: make(chan struct{}, reqs),
}
for i := 0; i < reqs; i++ {
cR.aReqs <- struct{}{}
}
return cR
}
// IsLimited returns true if the limit is not 0
func (cR *ConcReqs) IsLimited() bool {
return ConReqs.limit != 0
}
// Allocate will reserve a channel for the API call
func (cR *ConcReqs) Allocate() (err error) {
switch cR.strategy {
case MetaBusy:
if len(cR.aReqs) == 0 {
return ErrMaxConcurentRPCExceededNoCaps
}
fallthrough
case MetaQueue:
<-cR.aReqs // get from channel
}
return
}
// Deallocate will free a channel for the API call
func (cR *ConcReqs) Deallocate() {
cR.aReqs <- struct{}{}
return
}
type conn interface {
Read(b []byte) (n int, err error)
Write(b []byte) (n int, err error)
Close() error
LocalAddr() net.Addr
RemoteAddr() net.Addr
}
func newConcReqsGOBCodec(conn conn) rpc.ServerCodec {
return AnalizerWraperFunc(newConcReqsServerCodec(newGobServerCodec(conn)), MetaGOB, conn.RemoteAddr(), conn.LocalAddr())
}
func newConcReqsJSONCodec(conn conn) rpc.ServerCodec {
return AnalizerWraperFunc(newConcReqsServerCodec(jsonrpc.NewServerCodec(conn)), MetaJSON, conn.RemoteAddr(), conn.LocalAddr())
}
func newConcReqsServerCodec(sc rpc.ServerCodec) rpc.ServerCodec {
if !ConReqs.IsLimited() {
return sc
}
return &concReqsServerCodec{sc: sc}
}
type concReqsServerCodec struct {
sc rpc.ServerCodec
}
func (c *concReqsServerCodec) ReadRequestHeader(r *rpc.Request) error {
return c.sc.ReadRequestHeader(r)
}
func (c *concReqsServerCodec) ReadRequestBody(x interface{}) error {
if err := ConReqs.Allocate(); err != nil {
return err
}
return c.sc.ReadRequestBody(x)
}
func (c *concReqsServerCodec) WriteResponse(r *rpc.Response, x interface{}) error {
if r.Error == ErrMaxConcurentRPCExceededNoCaps.Error() {
r.Error = ErrMaxConcurentRPCExceeded.Error()
} else {
defer ConReqs.Deallocate()
}
return c.sc.WriteResponse(r, x)
}
func (c *concReqsServerCodec) Close() error { return c.sc.Close() }