netdata/netdata

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

package main

import (
    "errors"
    "fmt"
    "log/slog"
    "math/rand"
    "os"
    "path"

    "github.com/netdata/netdata/go/go.d.plugin/agent"
    "github.com/netdata/netdata/go/go.d.plugin/agent/module"
    "github.com/netdata/netdata/go/go.d.plugin/cli"
    "github.com/netdata/netdata/go/go.d.plugin/logger"
    "github.com/netdata/netdata/go/go.d.plugin/pkg/multipath"

    "github.com/jessevdk/go-flags"
)

var version = "v0.0.1-example"

type example struct{ module.Base }

func (example) Cleanup() {}

func (example) Init() error { return nil }

func (example) Check() error { return nil }

func (example) Charts() *module.Charts {
    return &module.Charts{
        {
            ID:    "random",
            Title: "A Random Number", Units: "random", Fam: "random",
            Dims: module.Dims{
                {ID: "random0", Name: "random 0"},
                {ID: "random1", Name: "random 1"},
            },
        },
    }
}
func (example) Configuration() any { return nil }

func (e *example) Collect() map[string]int64 {
    return map[string]int64{
        "random0": rand.Int63n(100),
        "random1": rand.Int63n(100),
    }
}

var (
    cd, _    = os.Getwd()
    name     = "goplugin"
    userDir  = os.Getenv("NETDATA_USER_CONFIG_DIR")
    stockDir = os.Getenv("NETDATA_STOCK_CONFIG_DIR")
)

func confDir(dirs []string) (mpath multipath.MultiPath) {
    if len(dirs) > 0 {
        return dirs
    }
    if userDir != "" && stockDir != "" {
        return multipath.New(
            userDir,
            stockDir,
        )
    }
    return multipath.New(
        path.Join(cd, "/../../../../etc/netdata"),
        path.Join(cd, "/../../../../usr/lib/netdata/conf.d"),
    )
}

func modulesConfDir(dirs []string) multipath.MultiPath {
    if len(dirs) > 0 {
        return dirs
    }
    if userDir != "" && stockDir != "" {
        return multipath.New(
            path.Join(userDir, name),
            path.Join(stockDir, name),
        )
    }
    return multipath.New(
        path.Join(cd, "/../../../../etc/netdata", name),
        path.Join(cd, "/../../../../usr/lib/netdata/conf.d", name),
    )
}

func main() {
    opt := parseCLI()

    if opt.Debug {
        logger.Level.Set(slog.LevelDebug)
    }
    if opt.Version {
        fmt.Println(version)
        os.Exit(0)
    }

    module.Register("example", module.Creator{
        Create: func() module.Module { return &example{} }},
    )

    p := agent.New(agent.Config{
        Name:                 name,
        ConfDir:              confDir(opt.ConfDir),
        ModulesConfDir:       modulesConfDir(opt.ConfDir),
        ModulesConfWatchPath: opt.WatchPath,
        RunModule:            opt.Module,
        MinUpdateEvery:       opt.UpdateEvery,
    })

    p.Run()
}

func parseCLI() *cli.Option {
    opt, err := cli.Parse(os.Args)
    var flagsErr *flags.Error
    if errors.As(err, &flagsErr) && errors.Is(flagsErr.Type, flags.ErrHelp) {
        os.Exit(0)
    } else {
        os.Exit(1)
    }
    return opt
}