ingress-nginx-helm/internal/ingress/metric/collectors/socket.go
Manuel Alejandro de Brito Fontes 108637bb1c Migrate to structured logging (klog)
2020-09-27 18:59:57 -03:00

457 lines
12 KiB
Go

/*
Copyright 2016 The Kubernetes 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 collectors
import (
"fmt"
"io"
"io/ioutil"
"net"
"os"
"syscall"
jsoniter "github.com/json-iterator/go"
"github.com/prometheus/client_golang/prometheus"
"k8s.io/apimachinery/pkg/util/sets"
"k8s.io/klog/v2"
)
type upstream struct {
Latency float64 `json:"upstreamLatency"`
ResponseLength float64 `json:"upstreamResponseLength"`
ResponseTime float64 `json:"upstreamResponseTime"`
//Status string `json:"upstreamStatus"`
}
type socketData struct {
Host string `json:"host"`
Status string `json:"status"`
ResponseLength float64 `json:"responseLength"`
Method string `json:"method"`
RequestLength float64 `json:"requestLength"`
RequestTime float64 `json:"requestTime"`
upstream
Namespace string `json:"namespace"`
Ingress string `json:"ingress"`
Service string `json:"service"`
Path string `json:"path"`
}
// SocketCollector stores prometheus metrics and ingress meta-data
type SocketCollector struct {
prometheus.Collector
requestTime *prometheus.HistogramVec
requestLength *prometheus.HistogramVec
responseTime *prometheus.HistogramVec
responseLength *prometheus.HistogramVec
upstreamLatency *prometheus.SummaryVec
bytesSent *prometheus.HistogramVec
requests *prometheus.CounterVec
listener net.Listener
metricMapping map[string]interface{}
hosts sets.String
metricsPerHost bool
}
var (
requestTags = []string{
"status",
"method",
"path",
"namespace",
"ingress",
"service",
}
)
// DefObjectives was removed in https://github.com/prometheus/client_golang/pull/262
// updating the library to latest version changed the output of the metrics
var defObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
// NewSocketCollector creates a new SocketCollector instance using
// the ingress watch namespace and class used by the controller
func NewSocketCollector(pod, namespace, class string, metricsPerHost bool) (*SocketCollector, error) {
socket := "/tmp/prometheus-nginx.socket"
// unix sockets must be unlink()ed before being used
_ = syscall.Unlink(socket)
listener, err := net.Listen("unix", socket)
if err != nil {
return nil, err
}
err = os.Chmod(socket, 0777)
if err != nil {
return nil, err
}
constLabels := prometheus.Labels{
"controller_namespace": namespace,
"controller_class": class,
"controller_pod": pod,
}
requestTags := requestTags
if metricsPerHost {
requestTags = append(requestTags, "host")
}
sc := &SocketCollector{
listener: listener,
metricsPerHost: metricsPerHost,
responseTime: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "response_duration_seconds",
Help: "The time spent on receiving the response from the upstream server",
Namespace: PrometheusNamespace,
ConstLabels: constLabels,
},
requestTags,
),
responseLength: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "response_size",
Help: "The response length (including request line, header, and request body)",
Namespace: PrometheusNamespace,
ConstLabels: constLabels,
},
requestTags,
),
requestTime: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "request_duration_seconds",
Help: "The request processing time in milliseconds",
Namespace: PrometheusNamespace,
ConstLabels: constLabels,
},
requestTags,
),
requestLength: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "request_size",
Help: "The request length (including request line, header, and request body)",
Namespace: PrometheusNamespace,
Buckets: prometheus.LinearBuckets(10, 10, 10), // 10 buckets, each 10 bytes wide.
ConstLabels: constLabels,
},
requestTags,
),
requests: prometheus.NewCounterVec(
prometheus.CounterOpts{
Name: "requests",
Help: "The total number of client requests.",
Namespace: PrometheusNamespace,
ConstLabels: constLabels,
},
[]string{"ingress", "namespace", "status", "service"},
),
bytesSent: prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Name: "bytes_sent",
Help: "The number of bytes sent to a client",
Namespace: PrometheusNamespace,
Buckets: prometheus.ExponentialBuckets(10, 10, 7), // 7 buckets, exponential factor of 10.
ConstLabels: constLabels,
},
requestTags,
),
upstreamLatency: prometheus.NewSummaryVec(
prometheus.SummaryOpts{
Name: "ingress_upstream_latency_seconds",
Help: "Upstream service latency per Ingress",
Namespace: PrometheusNamespace,
ConstLabels: constLabels,
Objectives: defObjectives,
},
[]string{"ingress", "namespace", "service"},
),
}
sc.metricMapping = map[string]interface{}{
prometheus.BuildFQName(PrometheusNamespace, "", "request_duration_seconds"): sc.requestTime,
prometheus.BuildFQName(PrometheusNamespace, "", "request_size"): sc.requestLength,
prometheus.BuildFQName(PrometheusNamespace, "", "response_duration_seconds"): sc.responseTime,
prometheus.BuildFQName(PrometheusNamespace, "", "response_size"): sc.responseLength,
prometheus.BuildFQName(PrometheusNamespace, "", "bytes_sent"): sc.bytesSent,
prometheus.BuildFQName(PrometheusNamespace, "", "ingress_upstream_latency_seconds"): sc.upstreamLatency,
}
return sc, nil
}
func (sc *SocketCollector) handleMessage(msg []byte) {
klog.V(5).InfoS("Metric", "message", string(msg))
// Unmarshal bytes
var statsBatch []socketData
err := jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal(msg, &statsBatch)
if err != nil {
klog.ErrorS(err, "Unexpected error deserializing JSON", "payload", string(msg))
return
}
for _, stats := range statsBatch {
if sc.metricsPerHost && !sc.hosts.Has(stats.Host) {
klog.V(3).InfoS("Skipping metric for host not being served", "host", stats.Host)
continue
}
// Note these must match the order in requestTags at the top
requestLabels := prometheus.Labels{
"status": stats.Status,
"method": stats.Method,
"path": stats.Path,
"namespace": stats.Namespace,
"ingress": stats.Ingress,
"service": stats.Service,
}
if sc.metricsPerHost {
requestLabels["host"] = stats.Host
}
collectorLabels := prometheus.Labels{
"namespace": stats.Namespace,
"ingress": stats.Ingress,
"status": stats.Status,
"service": stats.Service,
}
latencyLabels := prometheus.Labels{
"namespace": stats.Namespace,
"ingress": stats.Ingress,
"service": stats.Service,
}
requestsMetric, err := sc.requests.GetMetricWith(collectorLabels)
if err != nil {
klog.ErrorS(err, "Error fetching requests metric")
} else {
requestsMetric.Inc()
}
if stats.Latency != -1 {
latencyMetric, err := sc.upstreamLatency.GetMetricWith(latencyLabels)
if err != nil {
klog.ErrorS(err, "Error fetching latency metric")
} else {
latencyMetric.Observe(stats.Latency)
}
}
if stats.RequestTime != -1 {
requestTimeMetric, err := sc.requestTime.GetMetricWith(requestLabels)
if err != nil {
klog.ErrorS(err, "Error fetching request duration metric")
} else {
requestTimeMetric.Observe(stats.RequestTime)
}
}
if stats.RequestLength != -1 {
requestLengthMetric, err := sc.requestLength.GetMetricWith(requestLabels)
if err != nil {
klog.ErrorS(err, "Error fetching request length metric")
} else {
requestLengthMetric.Observe(stats.RequestLength)
}
}
if stats.ResponseTime != -1 {
responseTimeMetric, err := sc.responseTime.GetMetricWith(requestLabels)
if err != nil {
klog.ErrorS(err, "Error fetching upstream response time metric")
} else {
responseTimeMetric.Observe(stats.ResponseTime)
}
}
if stats.ResponseLength != -1 {
bytesSentMetric, err := sc.bytesSent.GetMetricWith(requestLabels)
if err != nil {
klog.ErrorS(err, "Error fetching bytes sent metric")
} else {
bytesSentMetric.Observe(stats.ResponseLength)
}
responseSizeMetric, err := sc.responseLength.GetMetricWith(requestLabels)
if err != nil {
klog.ErrorS(err, "Error fetching bytes sent metric")
} else {
responseSizeMetric.Observe(stats.ResponseLength)
}
}
}
}
// Start listen for connections in the unix socket and spawns a goroutine to process the content
func (sc *SocketCollector) Start() {
for {
conn, err := sc.listener.Accept()
if err != nil {
continue
}
go handleMessages(conn, sc.handleMessage)
}
}
// Stop stops unix listener
func (sc *SocketCollector) Stop() {
sc.listener.Close()
}
// RemoveMetrics deletes prometheus metrics from prometheus for ingresses and
// host that are not available anymore.
// Ref: https://godoc.org/github.com/prometheus/client_golang/prometheus#CounterVec.Delete
func (sc *SocketCollector) RemoveMetrics(ingresses []string, registry prometheus.Gatherer) {
mfs, err := registry.Gather()
if err != nil {
klog.ErrorS(err, "Error gathering metrics: %v")
return
}
// 1. remove metrics of removed ingresses
klog.V(2).InfoS("removing metrics", "ingresses", ingresses)
for _, mf := range mfs {
metricName := mf.GetName()
metric, ok := sc.metricMapping[metricName]
if !ok {
continue
}
toRemove := sets.NewString(ingresses...)
for _, m := range mf.GetMetric() {
labels := make(map[string]string, len(m.GetLabel()))
for _, labelPair := range m.GetLabel() {
labels[*labelPair.Name] = *labelPair.Value
}
// remove labels that are constant
deleteConstants(labels)
ns, ok := labels["namespace"]
if !ok {
continue
}
ing, ok := labels["ingress"]
if !ok {
continue
}
ingKey := fmt.Sprintf("%v/%v", ns, ing)
if !toRemove.Has(ingKey) {
continue
}
klog.V(2).Infof("Removing prometheus metric from histogram %v for ingress %v", metricName, ingKey)
h, ok := metric.(*prometheus.HistogramVec)
if ok {
removed := h.Delete(labels)
if !removed {
klog.V(2).InfoS("metric not removed", "name", metricName, "ingress", ingKey, "labels", labels)
}
}
s, ok := metric.(*prometheus.SummaryVec)
if ok {
removed := s.Delete(labels)
if !removed {
klog.V(2).InfoS("metric not removed", "name", metricName, "ingress", ingKey, "labels", labels)
}
}
}
}
}
// Describe implements prometheus.Collector
func (sc SocketCollector) Describe(ch chan<- *prometheus.Desc) {
sc.requestTime.Describe(ch)
sc.requestLength.Describe(ch)
sc.requests.Describe(ch)
sc.upstreamLatency.Describe(ch)
sc.responseTime.Describe(ch)
sc.responseLength.Describe(ch)
sc.bytesSent.Describe(ch)
}
// Collect implements the prometheus.Collector interface.
func (sc SocketCollector) Collect(ch chan<- prometheus.Metric) {
sc.requestTime.Collect(ch)
sc.requestLength.Collect(ch)
sc.requests.Collect(ch)
sc.upstreamLatency.Collect(ch)
sc.responseTime.Collect(ch)
sc.responseLength.Collect(ch)
sc.bytesSent.Collect(ch)
}
// SetHosts sets the hostnames that are being served by the ingress controller
// This set of hostnames is used to filter the metrics to be exposed
func (sc *SocketCollector) SetHosts(hosts sets.String) {
sc.hosts = hosts
}
// handleMessages process the content received in a network connection
func handleMessages(conn io.ReadCloser, fn func([]byte)) {
defer conn.Close()
data, err := ioutil.ReadAll(conn)
if err != nil {
return
}
fn(data)
}
func deleteConstants(labels prometheus.Labels) {
delete(labels, "controller_namespace")
delete(labels, "controller_class")
delete(labels, "controller_pod")
}