From 35820222c5415695ebe58e3496f04fb7582c55eb Mon Sep 17 00:00:00 2001
From: nyl1001 <602645105@qq.com>
Date: Wed, 11 Oct 2023 02:07:47 +0800
Subject: [PATCH] when remove node, clean up engine cache & remove prometheus
 metrics (#615)

---
 cluster/calcium/node.go |  8 ++++-
 metrics/handler.go      |  3 ++
 metrics/metrics.go      | 75 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 85 insertions(+), 1 deletion(-)

diff --git a/cluster/calcium/node.go b/cluster/calcium/node.go
index 212ee9fbb..49c73e6fe 100644
--- a/cluster/calcium/node.go
+++ b/cluster/calcium/node.go
@@ -7,6 +7,7 @@ import (
 	enginefactory "github.com/projecteru2/core/engine/factory"
 	enginetypes "github.com/projecteru2/core/engine/types"
 	"github.com/projecteru2/core/log"
+	"github.com/projecteru2/core/metrics"
 	"github.com/projecteru2/core/resource/plugins"
 	resourcetypes "github.com/projecteru2/core/resource/types"
 	"github.com/projecteru2/core/types"
@@ -89,7 +90,12 @@ func (c *Calcium) RemoveNode(ctx context.Context, nodename string) error {
 			},
 			// then: remove node resource metadata
 			func(ctx context.Context) error {
-				return c.rmgr.RemoveNode(ctx, nodename)
+				if err = c.rmgr.RemoveNode(ctx, nodename); err != nil {
+					return err
+				}
+				enginefactory.RemoveEngineFromCache(ctx, node.Endpoint, node.Ca, node.Cert, node.Key)
+				metrics.Client.RemoveInvalidNodes([]string{nodename})
+				return nil
 			},
 			// rollback: do nothing
 			func(ctx context.Context, failureByCond bool) error {
diff --git a/metrics/handler.go b/metrics/handler.go
index 0b8a18113..7fc556d8b 100644
--- a/metrics/handler.go
+++ b/metrics/handler.go
@@ -20,14 +20,17 @@ func (m *Metrics) ResourceMiddleware(cluster cluster.Cluster) func(http.Handler)
 			if err != nil {
 				logger.Error(ctx, err, "Get all nodes err")
 			}
+			activeNodes := make(map[string]*types.Node, 0)
 			for node := range nodes {
 				metrics, err := m.rmgr.GetNodeMetrics(ctx, node)
 				if err != nil {
 					logger.Error(ctx, err, "Get metrics failed")
 					continue
 				}
+				activeNodes[node.Name] = node
 				m.SendMetrics(ctx, metrics...)
 			}
+			m.DeleteInactiveNodesWithCache(ctx, activeNodes)
 			h.ServeHTTP(w, r)
 		})
 	}
diff --git a/metrics/metrics.go b/metrics/metrics.go
index aa311a140..762cd5117 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -6,12 +6,15 @@ import (
 	"strconv"
 	"sync"
 
+	enginefactory "github.com/projecteru2/core/engine/factory"
 	"github.com/projecteru2/core/log"
 	"github.com/projecteru2/core/resource"
 	"github.com/projecteru2/core/resource/cobalt"
 	plugintypes "github.com/projecteru2/core/resource/plugins/types"
 	"github.com/projecteru2/core/types"
 	"github.com/projecteru2/core/utils"
+	io_prometheus_client "github.com/prometheus/client_model/go"
+	"golang.org/x/exp/slices"
 
 	statsdlib "github.com/CMGS/statsd"
 	"github.com/prometheus/client_golang/prometheus"
@@ -85,6 +88,78 @@ func (m *Metrics) SendMetrics(ctx context.Context, metrics ...*plugintypes.Metri
 	}
 }
 
+func (m *Metrics) DeleteInactiveNodesWithCache(ctx context.Context, activeNodesMap map[string]*types.Node) {
+	metricNodeNameMap := m.getNodeNameMapFromMetrics()
+	// 计算差集
+	invalidNodes := make([]string, 0)
+	for nodeName := range metricNodeNameMap {
+		if node, exists := activeNodesMap[nodeName]; !exists {
+			invalidNodes = append(invalidNodes, nodeName)
+			enginefactory.RemoveEngineFromCache(ctx, node.Endpoint, node.Ca, node.Cert, node.Key)
+		}
+	}
+	m.RemoveInvalidNodes(invalidNodes)
+}
+
+func (m *Metrics) getNodeNameMapFromMetrics() map[string]bool {
+	metrics, _ := prometheus.DefaultGatherer.Gather()
+	nodeNameMap := make(map[string]bool, 0)
+	for _, metric := range metrics {
+		for _, mf := range metric.GetMetric() {
+			if len(mf.Label) == 0 {
+				continue
+			}
+			for _, label := range mf.Label {
+				if label.GetName() == "nodename" {
+					nodeNameMap[label.GetValue()] = true
+					break
+				}
+			}
+		}
+	}
+	return nodeNameMap
+}
+
+// RemoveInvalidNodes 清除多余的metric标签值
+func (m *Metrics) RemoveInvalidNodes(invalidNodes []string) {
+	if len(invalidNodes) == 0 {
+		return
+	}
+	for _, collector := range m.Collectors {
+		if collector == nil {
+			return
+		}
+		metrics, _ := prometheus.DefaultGatherer.Gather()
+		for _, metric := range metrics {
+			for _, mf := range metric.GetMetric() {
+				if len(mf.Label) == 0 {
+					continue
+				}
+
+				if !slices.ContainsFunc(mf.Label, func(label *io_prometheus_client.LabelPair) bool {
+					return label.GetName() == "nodename" && slices.ContainsFunc(invalidNodes, func(nodename string) bool {
+						return label.GetValue() == nodename
+					})
+				}) {
+					continue
+				}
+				labels := prometheus.Labels{}
+				for _, label := range mf.Label {
+					labels[label.GetName()] = label.GetValue()
+				}
+				// 删除符合条件的度量标签
+				switch c := collector.(type) {
+				case *prometheus.GaugeVec:
+					c.Delete(labels)
+				case *prometheus.CounterVec:
+					c.Delete(labels)
+				}
+			}
+		}
+		// 添加更多的条件来处理其他类型的Collector
+	}
+}
+
 // Lazy connect
 func (m *Metrics) checkConn(ctx context.Context) error {
 	if m.statsdClient != nil {