intergrate opensearch v2 (#5044)

intergrate opensearch

Signed-off-by: chengdehao <dehaocheng@kubesphere.io>

Co-authored-by: chengdehao <dehaocheng@kubesphere.io>

vendor/github.com/opensearch-project/opensearch-go/v2/opensearchtransport/metrics.go

@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// The OpenSearch Contributors require contributions made to
+// this file be licensed under the Apache-2.0 license or a
+// compatible open source license.
+//
+// Modifications Copyright OpenSearch Contributors. See
+// GitHub history for details.
+
+// Licensed to Elasticsearch B.V. under one or more contributor
+// license agreements. See the NOTICE file distributed with
+// this work for additional information regarding copyright
+// ownership. Elasticsearch B.V. licenses this file to you 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 opensearchtransport
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// Measurable defines the interface for transports supporting metrics.
+//
+type Measurable interface {
+	Metrics() (Metrics, error)
+}
+
+// connectionable defines the interface for transports returning a list of connections.
+//
+type connectionable interface {
+	connections() []*Connection
+}
+
+// Metrics represents the transport metrics.
+//
+type Metrics struct {
+	Requests  int         `json:"requests"`
+	Failures  int         `json:"failures"`
+	Responses map[int]int `json:"responses"`
+
+	Connections []fmt.Stringer `json:"connections"`
+}
+
+// ConnectionMetric represents metric information for a connection.
+//
+type ConnectionMetric struct {
+	URL       string     `json:"url"`
+	Failures  int        `json:"failures,omitempty"`
+	IsDead    bool       `json:"dead,omitempty"`
+	DeadSince *time.Time `json:"dead_since,omitempty"`
+
+	Meta struct {
+		ID    string   `json:"id"`
+		Name  string   `json:"name"`
+		Roles []string `json:"roles"`
+	} `json:"meta"`
+}
+
+// metrics represents the inner state of metrics.
+//
+type metrics struct {
+	sync.RWMutex
+
+	requests  int
+	failures  int
+	responses map[int]int
+
+	connections []*Connection
+}
+
+// Metrics returns the transport metrics.
+//
+func (c *Client) Metrics() (Metrics, error) {
+	if c.metrics == nil {
+		return Metrics{}, errors.New("transport metrics not enabled")
+	}
+	c.metrics.RLock()
+	defer c.metrics.RUnlock()
+
+	if lockable, ok := c.pool.(sync.Locker); ok {
+		lockable.Lock()
+		defer lockable.Unlock()
+	}
+
+	m := Metrics{
+		Requests:  c.metrics.requests,
+		Failures:  c.metrics.failures,
+		Responses: c.metrics.responses,
+	}
+
+	if pool, ok := c.pool.(connectionable); ok {
+		for _, c := range pool.connections() {
+			c.Lock()
+
+			cm := ConnectionMetric{
+				URL:      c.URL.String(),
+				IsDead:   c.IsDead,
+				Failures: c.Failures,
+			}
+
+			if !c.DeadSince.IsZero() {
+				cm.DeadSince = &c.DeadSince
+			}
+
+			if c.ID != "" {
+				cm.Meta.ID = c.ID
+			}
+
+			if c.Name != "" {
+				cm.Meta.Name = c.Name
+			}
+
+			if len(c.Roles) > 0 {
+				cm.Meta.Roles = c.Roles
+			}
+
+			m.Connections = append(m.Connections, cm)
+			c.Unlock()
+		}
+	}
+
+	return m, nil
+}
+
+// String returns the metrics as a string.
+//
+func (m Metrics) String() string {
+	var (
+		i int
+		b strings.Builder
+	)
+	b.WriteString("{")
+
+	b.WriteString("Requests:")
+	b.WriteString(strconv.Itoa(m.Requests))
+
+	b.WriteString(" Failures:")
+	b.WriteString(strconv.Itoa(m.Failures))
+
+	if len(m.Responses) > 0 {
+		b.WriteString(" Responses: ")
+		b.WriteString("[")
+
+		for code, num := range m.Responses {
+			b.WriteString(strconv.Itoa(code))
+			b.WriteString(":")
+			b.WriteString(strconv.Itoa(num))
+			if i+1 < len(m.Responses) {
+				b.WriteString(", ")
+			}
+			i++
+		}
+		b.WriteString("]")
+	}
+
+	b.WriteString(" Connections: [")
+	for i, c := range m.Connections {
+		b.WriteString(c.String())
+		if i+1 < len(m.Connections) {
+			b.WriteString(", ")
+		}
+		i++
+	}
+	b.WriteString("]")
+
+	b.WriteString("}")
+	return b.String()
+}
+
+// String returns the connection information as a string.
+//
+func (cm ConnectionMetric) String() string {
+	var b strings.Builder
+	b.WriteString("{")
+	b.WriteString(cm.URL)
+	if cm.IsDead {
+		fmt.Fprintf(&b, " dead=%v", cm.IsDead)
+	}
+	if cm.Failures > 0 {
+		fmt.Fprintf(&b, " failures=%d", cm.Failures)
+	}
+	if cm.DeadSince != nil {
+		fmt.Fprintf(&b, " dead_since=%s", cm.DeadSince.Local().Format(time.Stamp))
+	}
+	b.WriteString("}")
+	return b.String()
+}