minio/cmd/healthcheck-handler.go
Harshavardhana 166e998788
Fix healthcheck for NAS gateway (#6452)
It was expected that in gateway mode, we do not know
the backend types whereas in NAS gateway since its
an extension of FS mode (standalone) this leads to
an issue in LivenessCheckHandler() which would perpetually
return 503, this would affect all kubernetes, openshift
deployments of NAS gateway.
2018-09-11 13:44:10 -07:00

106 lines
3.5 KiB
Go

/*
* Minio Cloud Storage, (C) 2018 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 cmd
import (
"fmt"
"net/http"
"os"
"runtime"
"github.com/minio/minio/cmd/logger"
)
const (
minioHealthGoroutineThreshold = 1000
)
// ReadinessCheckHandler -- checks if there are more than threshold number of goroutines running,
// returns service unavailable.
// Readiness probes are used to detect situations where application is under heavy load
// and temporarily unable to serve. In a orchestrated setup like Kubernetes, containers reporting
// that they are not ready do not receive traffic through Kubernetes Services.
func ReadinessCheckHandler(w http.ResponseWriter, r *http.Request) {
if err := goroutineCountCheck(minioHealthGoroutineThreshold); err != nil {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
}
// LivenessCheckHandler -- checks if server can reach its disks internally.
// If not, server is considered to have failed and needs to be restarted.
// Liveness probes are used to detect situations where application (minio)
// has gone into a state where it can not recover except by being restarted.
func LivenessCheckHandler(w http.ResponseWriter, r *http.Request) {
ctx := newContext(r, w, "LivenessCheckHandler")
objLayer := newObjectLayerFn()
// Service not initialized yet
if objLayer == nil {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
s := objLayer.StorageInfo(ctx)
// Gateways don't provide disk info, also handle special case for NAS gateway.
if s.Backend.Type == Unknown || s.Backend.Type == BackendFS {
// ListBuckets to confirm gateway backend is up
if _, err := objLayer.ListBuckets(ctx); err != nil {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
return
}
var totalLocalDisks int
var erroredDisks int
for _, endpoint := range globalEndpoints {
// Check only if local disks are accessible, we do not have
// to reach to rest of the other servers in a distributed setup.
if endpoint.IsLocal {
totalLocalDisks++
// Attempt a stat to backend, any error resulting
// from this Stat() operation is considered as backend
// is not available, count them as errors.
if _, err := os.Stat(endpoint.Path); err != nil {
logger.LogIf(ctx, err)
erroredDisks++
}
}
}
// If all exported local disks have errored, we simply let kubernetes
// take us down.
if totalLocalDisks == erroredDisks {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
}
// checks threshold against total number of go-routines in the system and throws error if
// more than threshold go-routines are running.
func goroutineCountCheck(threshold int) error {
count := runtime.NumGoroutine()
if count > threshold {
return fmt.Errorf("too many goroutines (%d > %d)", count, threshold)
}
return nil
}