Files
mq-container/internal/metrics/metrics.go
Stephen Marshall 6c72c894f7 add multi-instance Queue Managers (#307)
* Initial code to implement multi-instance queue manager

* alter default mqsc to prevent race between listeners on standby startup

* Updates to multi-instance queue manager code

* initial multi instance test

* Multi-instance code improvements

* Multi instance fixes and first test

* configure queue manager

* Add mirror log filtering for mult-instance QMs

* Add log message for multi-instance enabled

* Improvements to container runtime logging

* refactor test

* Test active standby switch

* Improve createQueueManager function

* Test multi instance race

* wait

* multi instance mount tests

* skip race test

* mount tests

* no mount test

* single instance split mount tests

* readiness check

* More updates for handling standby queue manager

* Improve standby checks

* Minor fixes to miqm

* Fix logging of JSON errors

* Update copyrights

* Fix log includes
2019-05-01 14:42:25 +01:00

121 lines
3.0 KiB
Go

/*
© Copyright IBM Corporation 2018, 2019
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 metrics contains code to provide metrics for the queue manager
package metrics
import (
"context"
"fmt"
"net/http"
"time"
"github.com/ibm-messaging/mq-container/internal/logger"
"github.com/ibm-messaging/mq-container/internal/ready"
"github.com/prometheus/client_golang/prometheus"
)
const (
defaultPort = "9157"
)
var (
metricsEnabled = false
metricsServer = &http.Server{Addr: ":" + defaultPort}
)
// GatherMetrics gathers metrics for the queue manager
func GatherMetrics(qmName string, log *logger.Logger) {
// If running in standby mode - wait until the queue manager becomes active
for {
active, _ := ready.IsRunningAsActiveQM(qmName)
if active {
break
}
time.Sleep(requestTimeout * time.Second)
}
metricsEnabled = true
err := startMetricsGathering(qmName, log)
if err != nil {
log.Errorf("Metrics Error: %s", err.Error())
StopMetricsGathering(log)
}
}
// startMetricsGathering starts gathering metrics for the queue manager
func startMetricsGathering(qmName string, log *logger.Logger) error {
defer func() {
if r := recover(); r != nil {
log.Errorf("Metrics Error: %v", r)
}
}()
log.Println("Starting metrics gathering")
// Start processing metrics
go processMetrics(log, qmName)
// Wait for metrics to be ready before starting the Prometheus handler
<-startChannel
// Register metrics
metricsExporter := newExporter(qmName, log)
err := prometheus.Register(metricsExporter)
if err != nil {
return fmt.Errorf("Failed to register metrics: %v", err)
}
// Setup HTTP server to handle requests from Prometheus
http.Handle("/metrics", prometheus.Handler())
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(200)
// #nosec G104
w.Write([]byte("Status: METRICS ACTIVE"))
})
go func() {
err = metricsServer.ListenAndServe()
if err != nil && err != http.ErrServerClosed {
log.Errorf("Metrics Error: Failed to handle metrics request: %v", err)
StopMetricsGathering(log)
}
}()
return nil
}
// StopMetricsGathering stops gathering metrics for the queue manager
func StopMetricsGathering(log *logger.Logger) {
if metricsEnabled {
// Stop processing metrics
stopChannel <- true
// Shutdown HTTP server
timeout, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
err := metricsServer.Shutdown(timeout)
if err != nil {
log.Errorf("Failed to shutdown metrics server: %v", err)
}
}
}