nmon/internal/simagent/simagent_test.go

package simagent

import (
	"context"
	"strings"
	"testing"
	"time"

	"github.com/gosnmp/gosnmp"

	"github.com/v10networks/nmon/internal/snmprec"
)

const sample = `# comment
1.3.6.1.2.1.1.1.0|4|Linux box
1.3.6.1.2.1.1.2.0|6|1.3.6.1.4.1.8072.3.2.10
1.3.6.1.2.1.1.3.0|67|123456
1.3.6.1.2.1.1.4.0|4x|00ff7c
1.3.6.1.2.1.1.5.0|5|
1.3.6.1.2.1.4.20.1.1.10.0.0.1|64|10.0.0.1
1.3.6.1.2.1.2.2.1.5.1|66|1000000000
1.3.6.1.2.1.2.2.1.10.1|65|42
1.3.6.1.2.1.2.1.0|2|-3
1.3.6.1.2.1.31.1.1.1.6.1|70|18446744073709551615
1.3.6.1.2.1.1.9.0|68x|0102
1.3.6.1.2.1.1.9.0|68x|0304
.1.3.6.1.2.1.31.1.1.1.10.1|70:numeric|rate=125000,initial=7,wrap=999
`

func TestGetNextAndBulkSemantics(t *testing.T) {
	rec, err := snmprec.Parse(strings.NewReader(sample))
	if err != nil {
		t.Fatal(err)
	}
	a, err := Start(context.Background(), Config{Recording: rec})
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = a.Close() }() // test cleanup
	g := &gosnmp.GoSNMP{
		Target: a.Addr().Addr().String(), Port: a.Addr().Port(), Version: gosnmp.Version2c, Community: "public",
		Timeout: time.Second, Retries: 0,
	}
	if err := g.Connect(); err != nil {
		t.Fatal(err)
	}
	defer func() { _ = g.Close() }() // test cleanup

	p, err := g.GetNext([]string{"1.3.6.1.2.1.31.1.1.1.10.1"})
	if err != nil || len(p.Variables) != 1 || p.Variables[0].Type != gosnmp.EndOfMibView {
		t.Fatalf("past the end: %v %+v", err, p)
	}
	// 2 repeaters from the start, one non-repeater: non-repeater first, then rows interleaved.
	p, err = g.GetBulk([]string{"1.3.6.1.2.1.1.1.0", "1.3.6.1.2.1.1.3.0", "1.3.6.1.2.1.2.2.1.5"}, 1, 3)
	if err != nil {
		t.Fatal(err)
	}
	var names []string
	for _, v := range p.Variables {
		names = append(names, v.Name)
	}
	want := []string{
		".1.3.6.1.2.1.1.2.0",
		".1.3.6.1.2.1.1.4.0", ".1.3.6.1.2.1.2.2.1.5.1",
		".1.3.6.1.2.1.1.5.0", ".1.3.6.1.2.1.2.2.1.10.1",
		".1.3.6.1.2.1.1.9.0", ".1.3.6.1.2.1.4.20.1.1.10.0.0.1",
	}
	if strings.Join(names, ",") != strings.Join(want, ",") {
		t.Fatalf("bulk order:\n got %v\nwant %v", names, want)
	}
	// Bulk off the end stops once every repeater is exhausted.
	p, err = g.GetBulk([]string{"1.3.6.1.2.1.31.1.1.1.6.1"}, 0, 50)
	if err != nil || len(p.Variables) != 2 || p.Variables[1].Type != gosnmp.EndOfMibView {
		t.Fatalf("bulk tail: %v %+v", err, p.Variables)
	}
	// Set is refused.
	if p, err = g.Set([]gosnmp.SnmpPDU{{Name: "1.3.6.1.2.1.1.5.0", Type: gosnmp.OctetString, Value: "x"}}); err != nil || p.Error == gosnmp.NoError {
		t.Fatalf("set: %v %+v", err, p)
	}
}

func TestPool(t *testing.T) {
	rec, _ := snmprec.Parse(strings.NewReader(sample))
	cfgs := make([]Config, 100)
	for i := range cfgs {
		cfgs[i] = Config{Recording: rec}
	}
	var p Pool
	if err := p.Start(context.Background(), cfgs); err != nil {
		t.Fatal(err)
	}
	seen := map[uint16]bool{}
	for _, a := range p.Agents() {
		seen[a.Addr().Port()] = true
	}
	if len(seen) != 100 {
		t.Fatalf("%d distinct ports", len(seen))
	}
	if err := p.Close(); err != nil {
		t.Fatal(err)
	}
	if err := p.Start(context.Background(), []Config{{Recording: rec}, {}}); err == nil || len(p.Agents()) != 0 {
		t.Fatal("a failing config must leave the pool empty")
	}
}

func TestContextCancelStopsAgent(t *testing.T) {
	rec, _ := snmprec.Parse(strings.NewReader(sample))
	ctx, cancel := context.WithCancel(context.Background())
	a, err := Start(ctx, Config{Recording: rec})
	if err != nil {
		t.Fatal(err)
	}
	cancel()
	done := make(chan struct{})
	go func() { _ = a.Close(); close(done) }()
	select {
	case <-done:
	case <-time.After(5 * time.Second):
		t.Fatal("Close hung after cancel")
	}
}