add PrometheusAgent implementation

services/prometheus.go

@@ -0,0 +1,91 @@
+/*
+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 services
+
+import (
+	"sync"
+
+	"github.com/cgrates/cgrates/agents"
+	"github.com/cgrates/cgrates/config"
+	"github.com/cgrates/cgrates/cores"
+	"github.com/cgrates/cgrates/engine"
+	"github.com/cgrates/cgrates/utils"
+)
+
+// NewPrometheusAgent returns the Prometheus Agent
+func NewPrometheusAgent(cfg *config.CGRConfig, cm *engine.ConnManager, server *cores.Server,
+	srvDep map[string]*sync.WaitGroup) *PrometheusAgent {
+	return &PrometheusAgent{
+		cfg:    cfg,
+		cm:     cm,
+		server: server,
+		srvDep: srvDep,
+	}
+}
+
+// PrometheusAgent implements Agent interface
+type PrometheusAgent struct {
+	mu     sync.RWMutex
+	cfg    *config.CGRConfig
+	cm     *engine.ConnManager
+	server *cores.Server
+	srvDep map[string]*sync.WaitGroup
+
+	pa *agents.PrometheusAgent
+}
+
+// Start should handle the sercive start
+func (s *PrometheusAgent) Start() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.pa = agents.NewPrometheusAgent(s.cfg, s.cm)
+	s.server.RegisterHttpHandler(s.cfg.PrometheusAgentCfg().Path, s.pa)
+	return nil
+}
+
+// Reload handles configuration changes.
+func (s *PrometheusAgent) Reload() error {
+	return nil
+}
+
+// Shutdown stops the service.
+func (s *PrometheusAgent) Shutdown() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.pa = nil
+	return nil
+}
+
+// ServiceName returns the service name.
+func (s *PrometheusAgent) ServiceName() string {
+	return utils.PrometheusAgent
+}
+
+// ShouldRun returns if the service should be running.
+func (s *PrometheusAgent) ShouldRun() bool {
+	return s.cfg.PrometheusAgentCfg().Enabled
+}
+
+// IsRunning checks whether the service is running.
+func (s *PrometheusAgent) IsRunning() bool {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.pa != nil
+}