mirror of
https://github.com/prometheus/prometheus.git
synced 2024-12-30 07:59:40 -08:00
566 lines
18 KiB
Go
566 lines
18 KiB
Go
// Copyright 2016 The Prometheus Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package kubernetes
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import (
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"context"
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"fmt"
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"reflect"
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"strings"
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"sync"
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"time"
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"github.com/go-kit/log"
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"github.com/go-kit/log/level"
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"github.com/pkg/errors"
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/common/config"
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"github.com/prometheus/common/model"
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"github.com/prometheus/common/version"
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apiv1 "k8s.io/api/core/v1"
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disv1beta1 "k8s.io/api/discovery/v1beta1"
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"k8s.io/api/networking/v1beta1"
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metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
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"k8s.io/apimachinery/pkg/fields"
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"k8s.io/apimachinery/pkg/labels"
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"k8s.io/apimachinery/pkg/runtime"
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"k8s.io/apimachinery/pkg/watch"
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"k8s.io/client-go/kubernetes"
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"k8s.io/client-go/rest"
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"k8s.io/client-go/tools/cache"
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"k8s.io/client-go/tools/clientcmd"
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"github.com/prometheus/prometheus/discovery"
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"github.com/prometheus/prometheus/discovery/targetgroup"
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)
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const (
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// kubernetesMetaLabelPrefix is the meta prefix used for all meta labels.
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// in this discovery.
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metaLabelPrefix = model.MetaLabelPrefix + "kubernetes_"
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namespaceLabel = metaLabelPrefix + "namespace"
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metricsNamespace = "prometheus_sd_kubernetes"
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presentValue = model.LabelValue("true")
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)
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var (
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// Http header
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userAgent = fmt.Sprintf("Prometheus/%s", version.Version)
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// Custom events metric
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eventCount = prometheus.NewCounterVec(
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prometheus.CounterOpts{
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Namespace: metricsNamespace,
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Name: "events_total",
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Help: "The number of Kubernetes events handled.",
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},
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[]string{"role", "event"},
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)
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// DefaultSDConfig is the default Kubernetes SD configuration
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DefaultSDConfig = SDConfig{
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HTTPClientConfig: config.DefaultHTTPClientConfig,
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}
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)
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func init() {
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discovery.RegisterConfig(&SDConfig{})
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prometheus.MustRegister(eventCount)
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// Initialize metric vectors.
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for _, role := range []string{"endpointslice", "endpoints", "node", "pod", "service", "ingress"} {
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for _, evt := range []string{"add", "delete", "update"} {
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eventCount.WithLabelValues(role, evt)
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}
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}
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(&clientGoRequestMetricAdapter{}).Register(prometheus.DefaultRegisterer)
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(&clientGoWorkqueueMetricsProvider{}).Register(prometheus.DefaultRegisterer)
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}
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// Role is role of the service in Kubernetes.
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type Role string
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// The valid options for Role.
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const (
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RoleNode Role = "node"
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RolePod Role = "pod"
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RoleService Role = "service"
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RoleEndpoint Role = "endpoints"
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RoleEndpointSlice Role = "endpointslice"
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RoleIngress Role = "ingress"
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)
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// UnmarshalYAML implements the yaml.Unmarshaler interface.
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func (c *Role) UnmarshalYAML(unmarshal func(interface{}) error) error {
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if err := unmarshal((*string)(c)); err != nil {
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return err
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}
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switch *c {
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case RoleNode, RolePod, RoleService, RoleEndpoint, RoleEndpointSlice, RoleIngress:
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return nil
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default:
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return errors.Errorf("unknown Kubernetes SD role %q", *c)
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}
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}
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// SDConfig is the configuration for Kubernetes service discovery.
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type SDConfig struct {
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APIServer config.URL `yaml:"api_server,omitempty"`
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Role Role `yaml:"role"`
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KubeConfig string `yaml:"kubeconfig_file"`
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HTTPClientConfig config.HTTPClientConfig `yaml:",inline"`
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NamespaceDiscovery NamespaceDiscovery `yaml:"namespaces,omitempty"`
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Selectors []SelectorConfig `yaml:"selectors,omitempty"`
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}
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// Name returns the name of the Config.
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func (*SDConfig) Name() string { return "kubernetes" }
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// NewDiscoverer returns a Discoverer for the Config.
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func (c *SDConfig) NewDiscoverer(opts discovery.DiscovererOptions) (discovery.Discoverer, error) {
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return New(opts.Logger, c)
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}
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// SetDirectory joins any relative file paths with dir.
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func (c *SDConfig) SetDirectory(dir string) {
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c.HTTPClientConfig.SetDirectory(dir)
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c.KubeConfig = config.JoinDir(dir, c.KubeConfig)
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}
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type roleSelector struct {
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node resourceSelector
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pod resourceSelector
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service resourceSelector
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endpoints resourceSelector
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endpointslice resourceSelector
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ingress resourceSelector
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}
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type SelectorConfig struct {
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Role Role `yaml:"role,omitempty"`
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Label string `yaml:"label,omitempty"`
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Field string `yaml:"field,omitempty"`
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}
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type resourceSelector struct {
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label string
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field string
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}
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// UnmarshalYAML implements the yaml.Unmarshaler interface.
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func (c *SDConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
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*c = DefaultSDConfig
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type plain SDConfig
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err := unmarshal((*plain)(c))
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if err != nil {
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return err
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}
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if c.Role == "" {
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return errors.Errorf("role missing (one of: pod, service, endpoints, endpointslice, node, ingress)")
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}
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err = c.HTTPClientConfig.Validate()
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if err != nil {
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return err
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}
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if c.APIServer.URL != nil && c.KubeConfig != "" {
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// Api-server and kubeconfig_file are mutually exclusive
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return errors.Errorf("cannot use 'kubeconfig_file' and 'api_server' simultaneously")
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}
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if c.KubeConfig != "" && !reflect.DeepEqual(c.HTTPClientConfig, config.DefaultHTTPClientConfig) {
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// Kubeconfig_file and custom http config are mutually exclusive
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return errors.Errorf("cannot use a custom HTTP client configuration together with 'kubeconfig_file'")
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}
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if c.APIServer.URL == nil && !reflect.DeepEqual(c.HTTPClientConfig, config.DefaultHTTPClientConfig) {
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return errors.Errorf("to use custom HTTP client configuration please provide the 'api_server' URL explicitly")
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}
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foundSelectorRoles := make(map[Role]struct{})
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allowedSelectors := map[Role][]string{
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RolePod: {string(RolePod)},
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RoleService: {string(RoleService)},
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RoleEndpointSlice: {string(RolePod), string(RoleService), string(RoleEndpointSlice)},
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RoleEndpoint: {string(RolePod), string(RoleService), string(RoleEndpoint)},
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RoleNode: {string(RoleNode)},
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RoleIngress: {string(RoleIngress)},
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}
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for _, selector := range c.Selectors {
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if _, ok := foundSelectorRoles[selector.Role]; ok {
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return errors.Errorf("duplicated selector role: %s", selector.Role)
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}
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foundSelectorRoles[selector.Role] = struct{}{}
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if _, ok := allowedSelectors[c.Role]; !ok {
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return errors.Errorf("invalid role: %q, expecting one of: pod, service, endpoints, endpointslice, node or ingress", c.Role)
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}
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var allowed bool
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for _, role := range allowedSelectors[c.Role] {
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if role == string(selector.Role) {
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allowed = true
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break
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}
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}
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if !allowed {
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return errors.Errorf("%s role supports only %s selectors", c.Role, strings.Join(allowedSelectors[c.Role], ", "))
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}
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_, err := fields.ParseSelector(selector.Field)
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if err != nil {
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return err
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}
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_, err = labels.Parse(selector.Label)
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if err != nil {
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return err
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}
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}
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return nil
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}
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// NamespaceDiscovery is the configuration for discovering
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// Kubernetes namespaces.
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type NamespaceDiscovery struct {
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Names []string `yaml:"names"`
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}
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// UnmarshalYAML implements the yaml.Unmarshaler interface.
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func (c *NamespaceDiscovery) UnmarshalYAML(unmarshal func(interface{}) error) error {
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*c = NamespaceDiscovery{}
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type plain NamespaceDiscovery
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return unmarshal((*plain)(c))
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}
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// Discovery implements the discoverer interface for discovering
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// targets from Kubernetes.
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type Discovery struct {
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sync.RWMutex
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client kubernetes.Interface
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role Role
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logger log.Logger
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namespaceDiscovery *NamespaceDiscovery
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discoverers []discovery.Discoverer
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selectors roleSelector
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}
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func (d *Discovery) getNamespaces() []string {
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namespaces := d.namespaceDiscovery.Names
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if len(namespaces) == 0 {
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namespaces = []string{apiv1.NamespaceAll}
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}
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return namespaces
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}
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// New creates a new Kubernetes discovery for the given role.
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func New(l log.Logger, conf *SDConfig) (*Discovery, error) {
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if l == nil {
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l = log.NewNopLogger()
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}
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var (
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kcfg *rest.Config
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err error
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)
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if conf.KubeConfig != "" {
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kcfg, err = clientcmd.BuildConfigFromFlags("", conf.KubeConfig)
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if err != nil {
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return nil, err
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}
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} else if conf.APIServer.URL == nil {
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// Use the Kubernetes provided pod service account
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// as described in https://kubernetes.io/docs/admin/service-accounts-admin/
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kcfg, err = rest.InClusterConfig()
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if err != nil {
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return nil, err
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}
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level.Info(l).Log("msg", "Using pod service account via in-cluster config")
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} else {
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rt, err := config.NewRoundTripperFromConfig(conf.HTTPClientConfig, "kubernetes_sd", config.WithHTTP2Disabled())
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if err != nil {
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return nil, err
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}
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kcfg = &rest.Config{
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Host: conf.APIServer.String(),
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Transport: rt,
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}
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}
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kcfg.UserAgent = userAgent
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c, err := kubernetes.NewForConfig(kcfg)
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if err != nil {
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return nil, err
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}
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return &Discovery{
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client: c,
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logger: l,
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role: conf.Role,
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namespaceDiscovery: &conf.NamespaceDiscovery,
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discoverers: make([]discovery.Discoverer, 0),
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selectors: mapSelector(conf.Selectors),
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}, nil
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}
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func mapSelector(rawSelector []SelectorConfig) roleSelector {
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rs := roleSelector{}
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for _, resourceSelectorRaw := range rawSelector {
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switch resourceSelectorRaw.Role {
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case RoleEndpointSlice:
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rs.endpointslice.field = resourceSelectorRaw.Field
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rs.endpointslice.label = resourceSelectorRaw.Label
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case RoleEndpoint:
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rs.endpoints.field = resourceSelectorRaw.Field
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rs.endpoints.label = resourceSelectorRaw.Label
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case RoleIngress:
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rs.ingress.field = resourceSelectorRaw.Field
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rs.ingress.label = resourceSelectorRaw.Label
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case RoleNode:
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rs.node.field = resourceSelectorRaw.Field
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rs.node.label = resourceSelectorRaw.Label
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case RolePod:
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rs.pod.field = resourceSelectorRaw.Field
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rs.pod.label = resourceSelectorRaw.Label
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case RoleService:
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rs.service.field = resourceSelectorRaw.Field
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rs.service.label = resourceSelectorRaw.Label
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}
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}
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return rs
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}
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const resyncPeriod = 10 * time.Minute
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// Run implements the discoverer interface.
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func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
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d.Lock()
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namespaces := d.getNamespaces()
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switch d.role {
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case RoleEndpointSlice:
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for _, namespace := range namespaces {
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e := d.client.DiscoveryV1beta1().EndpointSlices(namespace)
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elw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.endpointslice.field
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options.LabelSelector = d.selectors.endpointslice.label
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return e.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.endpointslice.field
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options.LabelSelector = d.selectors.endpointslice.label
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return e.Watch(ctx, options)
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},
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}
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s := d.client.CoreV1().Services(namespace)
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slw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.service.field
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options.LabelSelector = d.selectors.service.label
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return s.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.service.field
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options.LabelSelector = d.selectors.service.label
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return s.Watch(ctx, options)
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},
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}
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p := d.client.CoreV1().Pods(namespace)
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plw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.pod.field
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options.LabelSelector = d.selectors.pod.label
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return p.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.pod.field
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options.LabelSelector = d.selectors.pod.label
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return p.Watch(ctx, options)
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},
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}
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eps := NewEndpointSlice(
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log.With(d.logger, "role", "endpointslice"),
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cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
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cache.NewSharedInformer(elw, &disv1beta1.EndpointSlice{}, resyncPeriod),
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cache.NewSharedInformer(plw, &apiv1.Pod{}, resyncPeriod),
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)
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d.discoverers = append(d.discoverers, eps)
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go eps.endpointSliceInf.Run(ctx.Done())
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go eps.serviceInf.Run(ctx.Done())
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go eps.podInf.Run(ctx.Done())
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}
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case RoleEndpoint:
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for _, namespace := range namespaces {
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e := d.client.CoreV1().Endpoints(namespace)
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elw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.endpoints.field
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options.LabelSelector = d.selectors.endpoints.label
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return e.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.endpoints.field
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options.LabelSelector = d.selectors.endpoints.label
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return e.Watch(ctx, options)
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},
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}
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s := d.client.CoreV1().Services(namespace)
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slw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.service.field
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options.LabelSelector = d.selectors.service.label
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return s.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.service.field
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options.LabelSelector = d.selectors.service.label
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return s.Watch(ctx, options)
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},
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}
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p := d.client.CoreV1().Pods(namespace)
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plw := &cache.ListWatch{
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
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options.FieldSelector = d.selectors.pod.field
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options.LabelSelector = d.selectors.pod.label
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return p.List(ctx, options)
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},
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WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
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options.FieldSelector = d.selectors.pod.field
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options.LabelSelector = d.selectors.pod.label
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return p.Watch(ctx, options)
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},
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}
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eps := NewEndpoints(
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log.With(d.logger, "role", "endpoint"),
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cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
|
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cache.NewSharedInformer(elw, &apiv1.Endpoints{}, resyncPeriod),
|
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cache.NewSharedInformer(plw, &apiv1.Pod{}, resyncPeriod),
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)
|
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d.discoverers = append(d.discoverers, eps)
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go eps.endpointsInf.Run(ctx.Done())
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go eps.serviceInf.Run(ctx.Done())
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go eps.podInf.Run(ctx.Done())
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}
|
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case RolePod:
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for _, namespace := range namespaces {
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p := d.client.CoreV1().Pods(namespace)
|
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plw := &cache.ListWatch{
|
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ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
|
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options.FieldSelector = d.selectors.pod.field
|
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options.LabelSelector = d.selectors.pod.label
|
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return p.List(ctx, options)
|
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},
|
|
WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
|
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options.FieldSelector = d.selectors.pod.field
|
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options.LabelSelector = d.selectors.pod.label
|
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return p.Watch(ctx, options)
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},
|
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}
|
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pod := NewPod(
|
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log.With(d.logger, "role", "pod"),
|
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cache.NewSharedInformer(plw, &apiv1.Pod{}, resyncPeriod),
|
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)
|
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d.discoverers = append(d.discoverers, pod)
|
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go pod.informer.Run(ctx.Done())
|
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}
|
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case RoleService:
|
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for _, namespace := range namespaces {
|
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s := d.client.CoreV1().Services(namespace)
|
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slw := &cache.ListWatch{
|
|
ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
|
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options.FieldSelector = d.selectors.service.field
|
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options.LabelSelector = d.selectors.service.label
|
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return s.List(ctx, options)
|
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},
|
|
WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
|
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options.FieldSelector = d.selectors.service.field
|
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options.LabelSelector = d.selectors.service.label
|
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return s.Watch(ctx, options)
|
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},
|
|
}
|
|
svc := NewService(
|
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log.With(d.logger, "role", "service"),
|
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cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
|
|
)
|
|
d.discoverers = append(d.discoverers, svc)
|
|
go svc.informer.Run(ctx.Done())
|
|
}
|
|
case RoleIngress:
|
|
for _, namespace := range namespaces {
|
|
i := d.client.NetworkingV1beta1().Ingresses(namespace)
|
|
ilw := &cache.ListWatch{
|
|
ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
|
|
options.FieldSelector = d.selectors.ingress.field
|
|
options.LabelSelector = d.selectors.ingress.label
|
|
return i.List(ctx, options)
|
|
},
|
|
WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
|
|
options.FieldSelector = d.selectors.ingress.field
|
|
options.LabelSelector = d.selectors.ingress.label
|
|
return i.Watch(ctx, options)
|
|
},
|
|
}
|
|
ingress := NewIngress(
|
|
log.With(d.logger, "role", "ingress"),
|
|
cache.NewSharedInformer(ilw, &v1beta1.Ingress{}, resyncPeriod),
|
|
)
|
|
d.discoverers = append(d.discoverers, ingress)
|
|
go ingress.informer.Run(ctx.Done())
|
|
}
|
|
case RoleNode:
|
|
nlw := &cache.ListWatch{
|
|
ListFunc: func(options metav1.ListOptions) (runtime.Object, error) {
|
|
options.FieldSelector = d.selectors.node.field
|
|
options.LabelSelector = d.selectors.node.label
|
|
return d.client.CoreV1().Nodes().List(ctx, options)
|
|
},
|
|
WatchFunc: func(options metav1.ListOptions) (watch.Interface, error) {
|
|
options.FieldSelector = d.selectors.node.field
|
|
options.LabelSelector = d.selectors.node.label
|
|
return d.client.CoreV1().Nodes().Watch(ctx, options)
|
|
},
|
|
}
|
|
node := NewNode(
|
|
log.With(d.logger, "role", "node"),
|
|
cache.NewSharedInformer(nlw, &apiv1.Node{}, resyncPeriod),
|
|
)
|
|
d.discoverers = append(d.discoverers, node)
|
|
go node.informer.Run(ctx.Done())
|
|
default:
|
|
level.Error(d.logger).Log("msg", "unknown Kubernetes discovery kind", "role", d.role)
|
|
}
|
|
|
|
var wg sync.WaitGroup
|
|
for _, dd := range d.discoverers {
|
|
wg.Add(1)
|
|
go func(d discovery.Discoverer) {
|
|
defer wg.Done()
|
|
d.Run(ctx, ch)
|
|
}(dd)
|
|
}
|
|
|
|
d.Unlock()
|
|
|
|
wg.Wait()
|
|
<-ctx.Done()
|
|
}
|
|
|
|
func lv(s string) model.LabelValue {
|
|
return model.LabelValue(s)
|
|
}
|
|
|
|
func send(ctx context.Context, ch chan<- []*targetgroup.Group, tg *targetgroup.Group) {
|
|
if tg == nil {
|
|
return
|
|
}
|
|
select {
|
|
case <-ctx.Done():
|
|
case ch <- []*targetgroup.Group{tg}:
|
|
}
|
|
}
|