1
0
Fork 0
mirror of https://github.com/prometheus-operator/prometheus-operator.git synced 2025-04-16 09:16:38 +00:00
prometheus-operator/pkg/admission/admission.go
Simon Pasquier ae74bdf0d9 Bump Go version to 1.19
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
2022-10-13 15:59:23 +02:00

340 lines
13 KiB
Go

// Copyright 2019 The prometheus-operator Authors
//
// 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 admission
import (
"encoding/json"
"fmt"
"io"
"net/http"
"strings"
"github.com/go-kit/log"
"github.com/go-kit/log/level"
validationv1alpha1 "github.com/prometheus-operator/prometheus-operator/pkg/alertmanager/validation/v1alpha1"
validationv1beta1 "github.com/prometheus-operator/prometheus-operator/pkg/alertmanager/validation/v1beta1"
monitoringv1 "github.com/prometheus-operator/prometheus-operator/pkg/apis/monitoring/v1"
monitoringv1alpha1 "github.com/prometheus-operator/prometheus-operator/pkg/apis/monitoring/v1alpha1"
monitoringv1beta1 "github.com/prometheus-operator/prometheus-operator/pkg/apis/monitoring/v1beta1"
promoperator "github.com/prometheus-operator/prometheus-operator/pkg/prometheus"
"github.com/prometheus/client_golang/prometheus"
"k8s.io/apimachinery/pkg/runtime"
"sigs.k8s.io/controller-runtime/pkg/webhook/conversion"
v1 "k8s.io/api/admission/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
kscheme "k8s.io/client-go/kubernetes/scheme"
)
const (
addFirstAnnotationPatch = `{ "op": "add", "path": "/metadata/annotations", "value": {"prometheus-operator-validated": "true"}}`
addAdditionalAnnotationPatch = `{ "op": "add", "path": "/metadata/annotations/prometheus-operator-validated", "value": "true" }`
errUnmarshalAdmission = "Cannot unmarshal admission request"
errUnmarshalRules = "Cannot unmarshal rules from spec"
errUnmarshalConfig = "Cannot unmarhsal config from spec"
group = "monitoring.coreos.com"
prometheusRuleResource = monitoringv1.PrometheusRuleName
prometheusRuleVersion = monitoringv1.Version
alertManagerConfigResource = monitoringv1beta1.AlertmanagerConfigName
alertManagerConfigKind = monitoringv1beta1.AlertmanagerConfigKind
prometheusRuleValidatePath = "/admission-prometheusrules/validate"
prometheusRuleMutatePath = "/admission-prometheusrules/mutate"
alertmanagerConfigValidatePath = "/admission-alertmanagerconfigs/validate"
convertPath = "/convert"
)
var (
deserializer = kscheme.Codecs.UniversalDeserializer()
prometheusRuleGVR = metav1.GroupVersionResource{
Group: group,
Version: prometheusRuleVersion,
Resource: prometheusRuleResource,
}
alertManagerConfigGR = metav1.GroupResource{
Group: group,
Resource: alertManagerConfigResource,
}
)
// Admission control for:
// 1. PrometheusRules (validation, mutation) - ensuring created resources can be loaded by Promethues
// 2. monitoringv1alpha1.AlertmanagerConfig (validation) - ensuring
type Admission struct {
promRuleValidationErrorsCounter prometheus.Counter
promRuleValidationTriggeredCounter prometheus.Counter
amConfValidationErrorsCounter prometheus.Counter
amConfValidationTriggeredCounter prometheus.Counter
logger log.Logger
wh *conversion.Webhook
}
func New(logger log.Logger) *Admission {
scheme := runtime.NewScheme()
if err := monitoringv1alpha1.AddToScheme(scheme); err != nil {
panic(err)
}
if err := monitoringv1beta1.AddToScheme(scheme); err != nil {
panic(err)
}
wh := &conversion.Webhook{}
if err := wh.InjectScheme(scheme); err != nil {
panic(fmt.Sprintf("failed to inject scheme into the webhook handler: %s", err))
}
return &Admission{
logger: logger,
wh: wh,
}
}
func (a *Admission) Register(mux *http.ServeMux) {
mux.HandleFunc(prometheusRuleValidatePath, a.servePrometheusRulesValidate)
mux.HandleFunc(prometheusRuleMutatePath, a.servePrometheusRulesMutate)
mux.HandleFunc(alertmanagerConfigValidatePath, a.serveAlertmanagerConfigValidate)
mux.HandleFunc(convertPath, a.serveConvert)
}
func (a *Admission) RegisterMetrics(
prometheusValidationTriggeredCounter,
prometheusValidationErrorsCounter,
alertManagerConfValidationTriggeredCounter,
alertManagerConfValidationErrorsCounter prometheus.Counter,
) {
a.promRuleValidationTriggeredCounter = prometheusValidationTriggeredCounter
a.promRuleValidationErrorsCounter = prometheusValidationErrorsCounter
a.amConfValidationTriggeredCounter = alertManagerConfValidationTriggeredCounter
a.amConfValidationErrorsCounter = alertManagerConfValidationErrorsCounter
}
type admitFunc func(ar v1.AdmissionReview) *v1.AdmissionResponse
func (a *Admission) servePrometheusRulesMutate(w http.ResponseWriter, r *http.Request) {
a.serveAdmission(w, r, a.mutatePrometheusRules)
}
func (a *Admission) servePrometheusRulesValidate(w http.ResponseWriter, r *http.Request) {
a.serveAdmission(w, r, a.validatePrometheusRules)
}
func (a *Admission) serveAlertmanagerConfigValidate(w http.ResponseWriter, r *http.Request) {
a.serveAdmission(w, r, a.validateAlertmanagerConfig)
}
func (a *Admission) serveConvert(w http.ResponseWriter, r *http.Request) {
a.wh.ServeHTTP(w, r)
}
func toAdmissionResponseFailure(message, resource string, errors []error) *v1.AdmissionResponse {
r := &v1.AdmissionResponse{
Result: &metav1.Status{
Details: &metav1.StatusDetails{
Causes: []metav1.StatusCause{}}}}
r.Result.Status = metav1.StatusFailure
r.Result.Reason = metav1.StatusReasonInvalid
r.Result.Code = http.StatusUnprocessableEntity
r.Result.Message = message
for _, err := range errors {
r.Result.Details.Name = resource
r.Result.Details.Causes = append(r.Result.Details.Causes, metav1.StatusCause{Message: err.Error()})
}
return r
}
func (a *Admission) serveAdmission(w http.ResponseWriter, r *http.Request, admit admitFunc) {
var body []byte
if r.Body != nil {
if data, err := io.ReadAll(r.Body); err == nil {
body = data
}
}
if len(body) == 0 {
level.Warn(a.logger).Log("msg", "request has no body")
http.Error(w, "request has no body", http.StatusBadRequest)
return
}
contentType := r.Header.Get("Content-Type")
if contentType != "application/json" {
level.Warn(a.logger).Log("msg", fmt.Sprintf("invalid Content-Type %s, want `application/json`", contentType))
http.Error(w, "invalid Content-Type, want `application/json`", http.StatusUnsupportedMediaType)
return
}
level.Debug(a.logger).Log("msg", "Received request", "content", string(body))
requestedAdmissionReview := v1.AdmissionReview{}
responseAdmissionReview := v1.AdmissionReview{}
if _, _, err := deserializer.Decode(body, nil, &requestedAdmissionReview); err != nil {
level.Warn(a.logger).Log("msg", "Unable to deserialize request", "err", err)
responseAdmissionReview.Response = toAdmissionResponseFailure("Unable to deserialize request", "", []error{err})
} else {
responseAdmissionReview.Response = admit(requestedAdmissionReview)
}
responseAdmissionReview.Response.UID = requestedAdmissionReview.Request.UID
responseAdmissionReview.APIVersion = requestedAdmissionReview.APIVersion
responseAdmissionReview.Kind = requestedAdmissionReview.Kind
respBytes, err := json.Marshal(responseAdmissionReview)
level.Debug(a.logger).Log("msg", "sending response", "content", string(respBytes))
if err != nil {
level.Error(a.logger).Log("msg", "Cannot serialize response", "err", err)
http.Error(w, fmt.Sprintf("could not serialize response: %v", err), http.StatusInternalServerError)
}
if _, err := w.Write(respBytes); err != nil {
level.Error(a.logger).Log("msg", "Cannot write response", "err", err)
http.Error(w, fmt.Sprintf("could not write response: %v", err), http.StatusInternalServerError)
}
}
func (a *Admission) mutatePrometheusRules(ar v1.AdmissionReview) *v1.AdmissionResponse {
level.Debug(a.logger).Log("msg", "Mutating prometheusrules")
if ar.Request.Resource != prometheusRuleGVR {
err := fmt.Errorf("expected resource to be %v, but received %v", prometheusRuleResource, ar.Request.Resource)
level.Warn(a.logger).Log("err", err)
return toAdmissionResponseFailure("Unexpected resource kind", prometheusRuleResource, []error{err})
}
rule := &PrometheusRules{}
if err := json.Unmarshal(ar.Request.Object.Raw, rule); err != nil {
level.Info(a.logger).Log("msg", errUnmarshalAdmission, "err", err)
return toAdmissionResponseFailure(errUnmarshalAdmission, prometheusRuleResource, []error{err})
}
patches, err := generatePatchesForNonStringLabelsAnnotations(rule.Spec.Raw)
if err != nil {
level.Info(a.logger).Log("msg", errUnmarshalRules, "err", err)
return toAdmissionResponseFailure(errUnmarshalRules, prometheusRuleResource, []error{err})
}
reviewResponse := &v1.AdmissionResponse{Allowed: true}
if len(rule.Annotations) == 0 {
patches = append(patches, addFirstAnnotationPatch)
} else {
patches = append(patches, addAdditionalAnnotationPatch)
}
pt := v1.PatchTypeJSONPatch
reviewResponse.PatchType = &pt
reviewResponse.Patch = []byte(fmt.Sprintf("[%s]", strings.Join(patches, ",")))
return reviewResponse
}
func (a *Admission) validatePrometheusRules(ar v1.AdmissionReview) *v1.AdmissionResponse {
a.incrementCounter(a.promRuleValidationTriggeredCounter)
level.Debug(a.logger).Log("msg", "Validating prometheusrules")
if ar.Request.Resource != prometheusRuleGVR {
err := fmt.Errorf("expected resource to be %v, but received %v", prometheusRuleResource, ar.Request.Resource)
level.Warn(a.logger).Log("err", err)
a.incrementCounter(a.promRuleValidationErrorsCounter)
return toAdmissionResponseFailure("Unexpected resource kind", prometheusRuleResource, []error{err})
}
promRule := &monitoringv1.PrometheusRule{}
if err := json.Unmarshal(ar.Request.Object.Raw, promRule); err != nil {
level.Info(a.logger).Log("msg", errUnmarshalRules, "err", err)
a.incrementCounter(a.promRuleValidationErrorsCounter)
return toAdmissionResponseFailure(errUnmarshalRules, prometheusRuleResource, []error{err})
}
errors := promoperator.ValidateRule(promRule.Spec)
if len(errors) != 0 {
const m = "Invalid rule"
level.Debug(a.logger).Log("msg", m, "content", promRule.Spec)
for _, err := range errors {
level.Info(a.logger).Log("msg", m, "err", err)
}
a.incrementCounter(a.promRuleValidationErrorsCounter)
return toAdmissionResponseFailure("Rules are not valid", prometheusRuleResource, errors)
}
return &v1.AdmissionResponse{Allowed: true}
}
func (a *Admission) validateAlertmanagerConfig(ar v1.AdmissionReview) *v1.AdmissionResponse {
a.incrementCounter(a.amConfValidationTriggeredCounter)
level.Debug(a.logger).Log("msg", "Validating alertmanagerconfigs")
gr := metav1.GroupResource{Group: ar.Request.Resource.Group, Resource: ar.Request.Resource.Resource}
if gr != alertManagerConfigGR {
err := fmt.Errorf("expected resource to be %v, but received %v", alertManagerConfigResource, ar.Request.Resource)
level.Warn(a.logger).Log("err", err)
a.incrementCounter(a.amConfValidationErrorsCounter)
return toAdmissionResponseFailure("Unexpected resource kind", alertManagerConfigResource, []error{err})
}
var amConf interface{}
switch ar.Request.Resource.Version {
case monitoringv1alpha1.Version:
amConf = &monitoringv1alpha1.AlertmanagerConfig{}
case monitoringv1beta1.Version:
amConf = &monitoringv1beta1.AlertmanagerConfig{}
default:
err := fmt.Errorf("expected resource version to be 'v1alpha1' or 'v1beta1', but received %v", ar.Request.Resource.Version)
return toAdmissionResponseFailure("Unexpected resource version", alertManagerConfigResource, []error{err})
}
if err := json.Unmarshal(ar.Request.Object.Raw, amConf); err != nil {
level.Info(a.logger).Log("msg", errUnmarshalConfig, "err", err)
a.incrementCounter(a.amConfValidationErrorsCounter)
return toAdmissionResponseFailure(errUnmarshalConfig, alertManagerConfigResource, []error{err})
}
var (
err error
)
switch ar.Request.Resource.Version {
case monitoringv1alpha1.Version:
err = validationv1alpha1.ValidateAlertmanagerConfig(amConf.(*monitoringv1alpha1.AlertmanagerConfig))
case monitoringv1beta1.Version:
err = validationv1beta1.ValidateAlertmanagerConfig(amConf.(*monitoringv1beta1.AlertmanagerConfig))
}
if err != nil {
msg := "invalid config"
level.Debug(a.logger).Log("msg", msg, "content", string(ar.Request.Object.Raw))
level.Info(a.logger).Log("msg", msg, "err", err)
a.incrementCounter(a.amConfValidationErrorsCounter)
return toAdmissionResponseFailure("AlertmanagerConfig is invalid", alertManagerConfigResource, []error{err})
}
return &v1.AdmissionResponse{Allowed: true}
}
// TODO (PhilipGough) - this can be removed when the following deprecated metrics are removed
// - prometheus_operator_rule_validation_triggered_total
// - prometheus_operator_rule_validation_errors_total
// - prometheus_operator_alertmanager_config_validation_errors_total
// - prometheus_operator_alertmanager_config_validation_triggered_total
func (a *Admission) incrementCounter(counter prometheus.Counter) {
if counter != nil {
counter.Inc()
}
}