Files
cgrates/services/dnsagent.go
2025-10-13 09:57:41 +02:00

145 lines
3.7 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 Affero 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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>
*/
package services
import (
"sync"
"github.com/cgrates/cgrates/agents"
"github.com/cgrates/cgrates/config"
"github.com/cgrates/cgrates/servmanager"
"github.com/cgrates/cgrates/utils"
)
// NewDNSAgent returns the DNS Agent
func NewDNSAgent(cfg *config.CGRConfig) *DNSAgent {
return &DNSAgent{
cfg: cfg,
stateDeps: NewStateDependencies([]string{utils.StateServiceUP, utils.StateServiceDOWN}),
}
}
// DNSAgent implements Agent interface
type DNSAgent struct {
mu sync.RWMutex
cfg *config.CGRConfig
stopChan chan struct{}
dns *agents.DNSAgent
stateDeps *StateDependencies // channel subscriptions for state changes
}
// Start should handle the service start
func (dns *DNSAgent) Start(shutdown *utils.SyncedChan, registry *servmanager.ServiceRegistry) (err error) {
srvDeps, err := WaitForServicesToReachState(utils.StateServiceUP,
[]string{
utils.ConnManager,
utils.FilterS,
},
registry, dns.cfg.GeneralCfg().ConnectTimeout)
if err != nil {
return err
}
cms := srvDeps[utils.ConnManager].(*ConnManagerService)
fs := srvDeps[utils.FilterS].(*FilterService)
dns.mu.Lock()
defer dns.mu.Unlock()
dns.dns, err = agents.NewDNSAgent(dns.cfg, fs.FilterS(), cms.ConnManager())
if err != nil {
dns.dns = nil
return
}
dns.stopChan = make(chan struct{})
go dns.listenAndServe(dns.stopChan, shutdown)
return
}
// Reload handles the change of config
func (dns *DNSAgent) Reload(shutdown *utils.SyncedChan, registry *servmanager.ServiceRegistry) (err error) {
srvDeps, err := WaitForServicesToReachState(utils.StateServiceUP,
[]string{
utils.ConnManager,
utils.FilterS,
},
registry, dns.cfg.GeneralCfg().ConnectTimeout)
if err != nil {
return err
}
cms := srvDeps[utils.ConnManager].(*ConnManagerService)
fs := srvDeps[utils.FilterS].(*FilterService)
dns.mu.Lock()
defer dns.mu.Unlock()
if dns.dns != nil {
close(dns.stopChan)
}
dns.dns, err = agents.NewDNSAgent(dns.cfg, fs.FilterS(), cms.ConnManager())
if err != nil {
dns.dns = nil
return
}
dns.dns.Lock()
defer dns.dns.Unlock()
dns.stopChan = make(chan struct{})
go dns.listenAndServe(dns.stopChan, shutdown)
return
}
func (dns *DNSAgent) listenAndServe(stopChan chan struct{}, shutdown *utils.SyncedChan) (err error) {
dns.dns.RLock()
defer dns.dns.RUnlock()
if err = dns.dns.ListenAndServe(stopChan); err != nil {
shutdown.CloseOnce() // stop the engine here
}
return
}
// Shutdown stops the service
func (dns *DNSAgent) Shutdown(_ *servmanager.ServiceRegistry) (err error) {
if dns.dns == nil {
return
}
close(dns.stopChan)
dns.mu.Lock()
defer dns.mu.Unlock()
dns.dns = nil
return
}
// ServiceName returns the service name
func (dns *DNSAgent) ServiceName() string {
return utils.DNSAgent
}
// ShouldRun returns if the service should be running
func (dns *DNSAgent) ShouldRun() bool {
return dns.cfg.DNSAgentCfg().Enabled
}
// StateChan returns signaling channel of specific state
func (dns *DNSAgent) StateChan(stateID string) chan struct{} {
return dns.stateDeps.StateChan(stateID)
}