firehol/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package mongo

import (
    "fmt"
    "strings"

    "github.com/netdata/netdata/go/plugins/plugin/go.d/agent/module"
)

// https://www.mongodb.com/docs/manual/reference/replica-states/#replica-set-member-states
var replicaSetMemberStates = map[string]int{
    "startup":    0,
    "primary":    1,
    "secondary":  2,
    "recovering": 3,
    "startup2":   5,
    "unknown":    6,
    "arbiter":    7,
    "down":       8,
    "rollback":   9,
    "removed":    10,
}

// TODO: deal with duplicates if we collect metrics from all cluster nodes
// should we only collect ReplSetStatus (at least by default) from primary nodes? (db.runCommand( { isMaster: 1 } ))
func (m *Mongo) collectReplSetStatus(mx map[string]int64) error {
    s, err := m.conn.replSetGetStatus()
    if err != nil {
        return fmt.Errorf("error get status of the replica set from mongo: %s", err)
    }

    seen := make(map[string]documentReplSetMember)

    for _, member := range s.Members {
        seen[member.Name] = member

        px := fmt.Sprintf("repl_set_member_%s_", member.Name)

        mx[px+"replication_lag"] = s.Date.Sub(member.OptimeDate).Milliseconds()

        for k, v := range replicaSetMemberStates {
            mx[px+"state_"+k] = boolToInt(member.State == v)
        }

        mx[px+"health_status_up"] = boolToInt(member.Health == 1)
        mx[px+"health_status_down"] = boolToInt(member.Health == 0)

        if member.Self == nil {
            mx[px+"uptime"] = member.Uptime
            if v := member.LastHeartbeatRecv; v != nil && !v.IsZero() {
                mx[px+"heartbeat_latency"] = s.Date.Sub(*v).Milliseconds()
            }
            if v := member.PingMs; v != nil {
                mx[px+"ping_rtt"] = *v
            }
        }
    }

    for name, member := range seen {
        if !m.replSetMembers[name] {
            m.replSetMembers[name] = true
            m.Debugf("new replica set member '%s': adding charts", name)
            m.addReplSetMemberCharts(member)
        }
    }

    for name := range m.replSetMembers {
        if _, ok := seen[name]; !ok {
            delete(m.replSetMembers, name)
            m.Debugf("stale replica set member '%s': removing charts", name)
            m.removeReplSetMemberCharts(name)
        }
    }

    return nil
}

func (m *Mongo) addReplSetMemberCharts(v documentReplSetMember) {
    charts := chartsTmplReplSetMember.Copy()

    if v.Self != nil {
        _ = charts.Remove(chartTmplReplSetMemberHeartbeatLatencyTime.ID)
        _ = charts.Remove(chartTmplReplSetMemberPingRTTTime.ID)
        _ = charts.Remove(chartTmplReplSetMemberUptime.ID)
    }

    for _, chart := range *charts {
        chart.ID = fmt.Sprintf(chart.ID, v.Name)
        chart.Labels = []module.Label{
            {Key: "repl_set_member", Value: v.Name},
        }
        for _, dim := range chart.Dims {
            dim.ID = fmt.Sprintf(dim.ID, v.Name)
        }
    }

    if err := m.Charts().Add(*charts...); err != nil {
        m.Warning(err)
    }
}

func (m *Mongo) removeReplSetMemberCharts(name string) {
    px := fmt.Sprintf("%s%s_", chartPxReplSetMember, name)

    for _, chart := range *m.Charts() {
        if strings.HasPrefix(chart.ID, px) {
            chart.MarkRemove()
            chart.MarkNotCreated()
        }
    }
}