| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | package pipeline |
| 4 | |
| 5 | import ( |
| 6 | "context" |
| 7 | "sync" |
| 8 | "time" |
| 9 | |
| 10 | "github.com/netdata/netdata/go/plugins/logger" |
| 11 | "github.com/netdata/netdata/go/plugins/plugin/agent/discovery/sd/model" |
| 12 | ) |
| 13 | |
| 14 | func newAccumulator() *accumulator { |
| 15 | return &accumulator{ |
| 16 | send: make(chan struct{}, 1), |
| 17 | sendEvery: time.Second * 2, |
| 18 | mux: &sync.Mutex{}, |
| 19 | tggs: make(map[string]model.TargetGroup), |
| 20 | } |
| 21 | } |
| 22 | |
| 23 | type accumulator struct { |
| 24 | *logger.Logger |
| 25 | discoverers []model.Discoverer |
| 26 | send chan struct{} |
| 27 | sendEvery time.Duration |
| 28 | mux *sync.Mutex |
| 29 | tggs map[string]model.TargetGroup |
| 30 | } |
| 31 | |
| 32 | func (a *accumulator) run(ctx context.Context, in chan []model.TargetGroup) { |
| 33 | updates := make(chan []model.TargetGroup) |
| 34 | |
| 35 | var wg sync.WaitGroup |
| 36 | for _, d := range a.discoverers { |
| 37 | wg.Add(1) |
| 38 | d := d |
| 39 | go func() { defer wg.Done(); a.runDiscoverer(ctx, d, updates) }() |
| 40 | } |
| 41 | |
| 42 | done := make(chan struct{}) |
| 43 | go func() { defer close(done); wg.Wait() }() |
| 44 | |
| 45 | tk := time.NewTicker(a.sendEvery) |
| 46 | defer tk.Stop() |
| 47 | |
| 48 | for { |
| 49 | select { |
| 50 | case <-ctx.Done(): |
| 51 | select { |
| 52 | case <-done: |
| 53 | a.Info("all discoverers exited") |
| 54 | case <-time.After(time.Second * 10): |
| 55 | a.Warning("not all discoverers exited") |
| 56 | } |
| 57 | a.finalSend(ctx, in) |
| 58 | return |
| 59 | case <-done: |
| 60 | if !isDone(ctx) { |
| 61 | a.Info("all discoverers exited before ctx done") |
| 62 | } else { |
| 63 | a.Info("all discoverers exited") |
| 64 | } |
| 65 | a.finalSend(ctx, in) |
| 66 | return |
| 67 | case <-tk.C: |
| 68 | select { |
| 69 | case <-a.send: |
| 70 | a.trySend(in) |
| 71 | default: |
| 72 | } |
| 73 | } |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | func (a *accumulator) runDiscoverer(ctx context.Context, d model.Discoverer, updates chan []model.TargetGroup) { |
| 78 | done := make(chan struct{}) |
| 79 | go func() { defer close(done); d.Discover(ctx, updates) }() |
| 80 | |
| 81 | for { |
| 82 | select { |
| 83 | case <-ctx.Done(): |
| 84 | select { |
| 85 | case <-done: |
| 86 | case <-time.After(time.Second * 10): |
| 87 | a.Warningf("discoverer '%v' didn't exit on ctx done", d) |
| 88 | } |
| 89 | return |
| 90 | case <-done: |
| 91 | if !isDone(ctx) { |
| 92 | a.Infof("discoverer '%v' exited before ctx done", d) |
| 93 | } |
| 94 | return |
| 95 | case tggs := <-updates: |
| 96 | a.mux.Lock() |
| 97 | a.groupsUpdate(tggs) |
| 98 | a.mux.Unlock() |
| 99 | a.triggerSend() |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | func (a *accumulator) trySend(in chan<- []model.TargetGroup) { |
| 105 | a.mux.Lock() |
| 106 | defer a.mux.Unlock() |
| 107 | |
| 108 | select { |
| 109 | case in <- a.groupsList(): |
| 110 | a.groupsReset() |
| 111 | default: |
| 112 | a.triggerSend() |
| 113 | } |
| 114 | } |
| 115 | |
| 116 | func (a *accumulator) finalSend(ctx context.Context, in chan<- []model.TargetGroup) { |
| 117 | a.mux.Lock() |
| 118 | tggs := a.groupsList() |
| 119 | if len(tggs) == 0 { |
| 120 | a.mux.Unlock() |
| 121 | return |
| 122 | } |
| 123 | a.mux.Unlock() |
| 124 | |
| 125 | select { |
| 126 | case in <- tggs: |
| 127 | a.mux.Lock() |
| 128 | a.groupsReset() |
| 129 | a.mux.Unlock() |
| 130 | return |
| 131 | default: |
| 132 | } |
| 133 | |
| 134 | select { |
| 135 | case <-ctx.Done(): |
| 136 | case in <- tggs: |
| 137 | a.mux.Lock() |
| 138 | a.groupsReset() |
| 139 | a.mux.Unlock() |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | func (a *accumulator) triggerSend() { |
| 144 | select { |
| 145 | case a.send <- struct{}{}: |
| 146 | default: |
| 147 | } |
| 148 | } |
| 149 | |
| 150 | func (a *accumulator) groupsUpdate(tggs []model.TargetGroup) { |
| 151 | for _, tgg := range tggs { |
| 152 | a.tggs[tgg.Source()] = tgg |
| 153 | } |
| 154 | } |
| 155 | |
| 156 | func (a *accumulator) groupsReset() { |
| 157 | for key := range a.tggs { |
| 158 | delete(a.tggs, key) |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | func (a *accumulator) groupsList() []model.TargetGroup { |
| 163 | tggs := make([]model.TargetGroup, 0, len(a.tggs)) |
| 164 | for _, tgg := range a.tggs { |
| 165 | if tgg != nil { |
| 166 | tggs = append(tggs, tgg) |
| 167 | } |
| 168 | } |
| 169 | return tggs |
| 170 | } |
| 171 | |
| 172 | func isDone(ctx context.Context) bool { |
| 173 | select { |
| 174 | case <-ctx.Done(): |
| 175 | return true |
| 176 | default: |
| 177 | return false |
| 178 | } |
| 179 | } |