Files
kubesphere/pkg/apiserver/auditing/backend.go
2020-06-23 16:26:24 +08:00

130 lines
2.8 KiB
Go

package auditing
import (
"bytes"
"context"
"crypto/tls"
"encoding/json"
"k8s.io/klog"
"kubesphere.io/kubesphere/pkg/apiserver/auditing/v1alpha1"
"net/http"
"time"
)
const (
WaitTimeout = time.Second
WebhookURL = "https://kube-auditing-webhook-svc.kubesphere-logging-system.svc:443/audit/webhook/event"
)
type Backend struct {
url string
channelCapacity int
semCh chan interface{}
cache chan *v1alpha1.EventList
client http.Client
sendTimeout time.Duration
waitTimeout time.Duration
stopCh <-chan struct{}
}
func NewBackend(url string, channelCapacity int, cache chan *v1alpha1.EventList, sendTimeout time.Duration, stopCh <-chan struct{}) *Backend {
b := Backend{
url: url,
semCh: make(chan interface{}, channelCapacity),
channelCapacity: channelCapacity,
waitTimeout: WaitTimeout,
cache: cache,
sendTimeout: sendTimeout,
stopCh: stopCh,
}
if len(b.url) == 0 {
b.url = WebhookURL
}
b.client = http.Client{
Transport: &http.Transport{
TLSClientConfig: &tls.Config{
InsecureSkipVerify: true,
},
},
Timeout: b.sendTimeout,
}
go b.worker()
return &b
}
func (b *Backend) worker() {
for {
var event *v1alpha1.EventList
select {
case event = <-b.cache:
if event == nil {
break
}
case <-b.stopCh:
break
}
send := func(event *v1alpha1.EventList) {
ctx, cancel := context.WithTimeout(context.Background(), b.waitTimeout)
defer cancel()
select {
case <-ctx.Done():
klog.Errorf("get goroutine for audit(%s) timeout", event.Items[0].AuditID)
return
case b.semCh <- struct{}{}:
}
defer func() {
<-b.semCh
}()
bs, err := b.eventToBytes(event)
if err != nil {
klog.V(6).Infof("json marshal error, %s", err)
return
}
klog.V(8).Infof("%s", string(bs))
response, err := b.client.Post(b.url, "application/json", bytes.NewBuffer(bs))
if err != nil {
klog.Errorf("send audit event[%s] error, %s", event.Items[0].AuditID, err)
return
}
if response.StatusCode != http.StatusOK {
klog.Errorf("send audit event[%s] error[%d]", event.Items[0].AuditID, response.StatusCode)
return
}
}
go send(event)
}
}
func (b *Backend) eventToBytes(event *v1alpha1.EventList) ([]byte, error) {
bs, err := json.Marshal(event)
if err != nil {
// Normally, the serialization failure is caused by the failure of ResponseObject serialization.
// To ensure the integrity of the auditing event to the greatest extent,
// it is necessary to delete ResponseObject and and then try to serialize again.
if event.Items[0].ResponseObject != nil {
event.Items[0].ResponseObject = nil
return json.Marshal(event)
}
return nil, err
}
return bs, err
}