minio/cmd/consolelogger.go
2020-03-20 15:14:14 -07:00

140 lines
3.7 KiB
Go

/*
* MinIO Cloud Storage, (C) 2019 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 (
ring "container/ring"
"context"
"sync"
"github.com/minio/minio/cmd/logger"
"github.com/minio/minio/cmd/logger/message/log"
"github.com/minio/minio/cmd/logger/target/console"
xnet "github.com/minio/minio/pkg/net"
"github.com/minio/minio/pkg/pubsub"
)
// number of log messages to buffer
const defaultLogBufferCount = 10000
//HTTPConsoleLoggerSys holds global console logger state
type HTTPConsoleLoggerSys struct {
sync.RWMutex
pubsub *pubsub.PubSub
console *console.Target
nodeName string
logBuf *ring.Ring
}
func mustGetNodeName(endpointZones EndpointZones) (nodeName string) {
host, err := xnet.ParseHost(GetLocalPeer(endpointZones))
if err != nil {
logger.FatalIf(err, "Unable to start console logging subsystem")
}
if globalIsDistXL {
nodeName = host.Name
}
return nodeName
}
// NewConsoleLogger - creates new HTTPConsoleLoggerSys with all nodes subscribed to
// the console logging pub sub system
func NewConsoleLogger(ctx context.Context) *HTTPConsoleLoggerSys {
ps := pubsub.New()
return &HTTPConsoleLoggerSys{
pubsub: ps,
console: console.New(),
logBuf: ring.New(defaultLogBufferCount),
}
}
// SetNodeName - sets the node name if any after distributed setup has initialized
func (sys *HTTPConsoleLoggerSys) SetNodeName(endpointZones EndpointZones) {
sys.nodeName = mustGetNodeName(endpointZones)
}
// HasLogListeners returns true if console log listeners are registered
// for this node or peers
func (sys *HTTPConsoleLoggerSys) HasLogListeners() bool {
return sys != nil && sys.pubsub.HasSubscribers()
}
// Subscribe starts console logging for this node.
func (sys *HTTPConsoleLoggerSys) Subscribe(subCh chan interface{}, doneCh chan struct{}, node string, last int, logKind string, filter func(entry interface{}) bool) {
// Enable console logging for remote client.
if !sys.HasLogListeners() {
logger.AddTarget(sys)
}
cnt := 0
// by default send all console logs in the ring buffer unless node or limit query parameters
// are set.
var lastN []log.Info
if last > defaultLogBufferCount || last <= 0 {
last = defaultLogBufferCount
}
lastN = make([]log.Info, last)
sys.RLock()
sys.logBuf.Do(func(p interface{}) {
if p != nil {
lg, ok := p.(log.Info)
if ok && lg.SendLog(node, logKind) {
lastN[cnt%last] = lg
cnt++
}
}
})
sys.RUnlock()
// send last n console log messages in order filtered by node
if cnt > 0 {
for i := 0; i < last; i++ {
entry := lastN[(cnt+i)%last]
if (entry == log.Info{}) {
continue
}
select {
case subCh <- entry:
case <-doneCh:
return
}
}
}
sys.pubsub.Subscribe(subCh, doneCh, filter)
}
// Send log message 'e' to console and publish to console
// log pubsub system
func (sys *HTTPConsoleLoggerSys) Send(e interface{}, logKind string) error {
var lg log.Info
switch e := e.(type) {
case log.Entry:
lg = log.Info{Entry: e, NodeName: sys.nodeName}
case string:
lg = log.Info{ConsoleMsg: e, NodeName: sys.nodeName}
}
sys.pubsub.Publish(lg)
sys.Lock()
// add log to ring buffer
sys.logBuf.Value = lg
sys.logBuf = sys.logBuf.Next()
sys.Unlock()
return sys.console.Send(e, string(logger.All))
}