netdata/netdata

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

package envoy

import (
    _ "embed"
    "errors"
    "time"

    "github.com/netdata/netdata/go/go.d.plugin/agent/module"
    "github.com/netdata/netdata/go/go.d.plugin/pkg/prometheus"
    "github.com/netdata/netdata/go/go.d.plugin/pkg/web"
)

//go:embed "config_schema.json"
var configSchema string

func init() {
    module.Register("envoy", module.Creator{
        JobConfigSchema: configSchema,
        Create:          func() module.Module { return New() },
        Config:          func() any { return &Config{} },
    })
}

func New() *Envoy {
    return &Envoy{
        Config: Config{
            HTTP: web.HTTP{
                Request: web.Request{
                    URL: "http://127.0.0.1:9091/stats/prometheus",
                },
                Client: web.Client{
                    Timeout: web.Duration(time.Second),
                },
            },
        },

        charts: &module.Charts{},

        servers:                 make(map[string]bool),
        clusterMgrs:             make(map[string]bool),
        clusterUpstream:         make(map[string]bool),
        listenerMgrs:            make(map[string]bool),
        listenerAdminDownstream: make(map[string]bool),
        listenerDownstream:      make(map[string]bool),
    }
}

type Config struct {
    UpdateEvery int `yaml:"update_every,omitempty" json:"update_every"`
    web.HTTP    `yaml:",inline" json:""`
}

type Envoy struct {
    module.Base
    Config `yaml:",inline" json:""`

    charts *module.Charts

    prom prometheus.Prometheus

    servers                 map[string]bool
    clusterMgrs             map[string]bool
    clusterUpstream         map[string]bool
    listenerMgrs            map[string]bool
    listenerAdminDownstream map[string]bool
    listenerDownstream      map[string]bool
}

func (e *Envoy) Configuration() any {
    return e.Config
}

func (e *Envoy) Init() error {
    if err := e.validateConfig(); err != nil {
        e.Errorf("config validation: %v", err)
        return err
    }

    prom, err := e.initPrometheusClient()
    if err != nil {
        e.Errorf("init Prometheus client: %v", err)
        return err
    }
    e.prom = prom

    return nil
}

func (e *Envoy) Check() error {
    mx, err := e.collect()
    if err != nil {
        e.Error(err)
        return err
    }
    if len(mx) == 0 {
        return errors.New("no metrics collected")

    }
    return nil
}

func (e *Envoy) Charts() *module.Charts {
    return e.charts
}

func (e *Envoy) Collect() map[string]int64 {
    mx, err := e.collect()
    if err != nil {
        e.Error(err)
    }

    if len(mx) == 0 {
        return nil
    }
    return mx
}

func (e *Envoy) Cleanup() {
    if e.prom == nil || e.prom.HTTPClient() == nil {
        return
    }

    e.prom.HTTPClient().CloseIdleConnections()
}