WIP: check_ping

Changes

@@ -1,5 +1,8 @@
 This file documents the revision history for the SNClient+ agent.
 
+next:
+         - add check_ping
+
 0.25     Fri Jun 14 14:34:25 CEST 2024
          - update node exporter to 1.8.1
          - migrate v3 to github.com/shirou/gopsutil/v4

packaging/snclient.ini

@@ -55,6 +55,9 @@ CheckSystemUnix = enabled
 ; CheckDisk - Controls wether check_drivesize is allowed or not.
 CheckDisk = enabled
 
+; CheckNet - Controls wether check_ping is allowed or not.
+CheckNet = disabled
+
 ; CheckWMI - Controls wether check_wmi is allowed or not.
 CheckWMI = disabled
 

pkg/snclient/check_ping.go

@@ -0,0 +1,103 @@
+package snclient
+
+import (
+	"context"
+	"fmt"
+	"runtime"
+)
+
+func init() {
+	AvailableChecks["check_ping"] = CheckEntry{"check_ping", NewCheckPing}
+}
+
+type CheckPing struct {
+	snc     *Agent
+	hosts   []string
+	timeout int64
+	count   int64
+}
+
+func NewCheckPing() CheckHandler {
+	return &CheckPing{
+		hosts:   []string{},
+		timeout: 500,
+		count:   1,
+	}
+}
+
+func (l *CheckPing) Build() *CheckData {
+	return &CheckData{
+		name:         "check_ping",
+		description:  "Checks a remote host availability.",
+		implemented:  ALL,
+		hasInventory: NoInventory,
+		result: &CheckResult{
+			State: CheckExitOK,
+		},
+		args: map[string]CheckArgument{
+			"host":    {value: &l.hosts, description: "The remote host to ping."},
+			"hosts":   {value: &l.hosts, description: "Alias for host."},
+			"timeout": {value: &l.timeout, description: "Ping timeout in milliseconds. Default: 500ms"},
+			"count":   {value: &l.count, description: "Number of packets to send. Default: 1"},
+		},
+		defaultWarning:  "time > 60 or loss > 5%",
+		defaultCritical: "time > 100 or loss > 10%",
+		okSyntax:        "%(status): All %(count) hosts are ok",
+		detailSyntax:    "${ip} Packet loss = ${loss}%, RTA = ${time}ms",
+		topSyntax:       "${status}: ${ok_count}/${count} (${problem_list})",
+		emptyState:      CheckExitUnknown,
+		emptySyntax:     "No hosts found",
+		attributes: []CheckAttribute{
+			{name: "host", description: "The host name or ip address (as given on command line)"},
+			{name: "ip", description: "The resolved ip address"},
+			{name: "loss", description: "Packet loss (in percent)"},
+			{name: "recv", description: "Number of packets received from the host"},
+			{name: "sent", description: "Number of packets sent to the host"},
+			{name: "timeout", description: "Number of packets which timed out from the host"},
+			{name: "time", description: "Round trip time in ms"},
+		},
+		exampleDefault: `
+    check_ping host=omd.consol.de
+    OK - TODO: ...
+	`,
+		exampleArgs: `host=omd.consol.de timeout=100 count=2`,
+	}
+}
+
+func (l *CheckPing) Check(ctx context.Context, snc *Agent, check *CheckData, _ []Argument) (*CheckResult, error) {
+	l.snc = snc
+
+	enabled, _, _ := snc.config.Section("/modules").GetBool("CheckNet")
+	if !enabled {
+		return nil, fmt.Errorf("module CheckNet is not enabled in /modules section")
+	}
+
+	if len(l.hosts) == 0 {
+		return nil, fmt.Errorf("must specify at least one host")
+	}
+
+	switch runtime.GOOS {
+	case "linux":
+		for _, host := range l.hosts {
+			err := l.addPingLinux(ctx, check, host)
+			if err != nil {
+				return nil, err
+			}
+		}
+	default:
+		return nil, fmt.Errorf("os %s is not supported", runtime.GOOS)
+	}
+
+	return check.Finalize()
+}
+
+func (l *CheckPing) addPingLinux(ctx context.Context, check *CheckData, host string) error {
+	output, stderr, _, err := l.snc.execCommand(ctx, fmt.Sprintf("ping %s -c %d -W %d", host, l.count, l.timeout), DefaultCmdTimeout)
+	if err != nil {
+		return fmt.Errorf("ping failed: %s\n%s", err.Error(), stderr)
+	}
+
+	log.Debugf("%s", output)
+
+	return nil
+}

pkg/snclient/check_ping_test.go

@@ -0,0 +1,26 @@
+package snclient
+
+import (
+	"regexp"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCheckPing(t *testing.T) {
+	config := `
+[/modules]
+CheckBuiltinPlugins = enabled
+`
+	snc := StartTestAgent(t, config)
+
+	res := snc.RunCheck("check_ping", []string{"host=127.0.0.1", "count=1", "timeout=5000"})
+	assert.Equalf(t, CheckExitOK, res.State, "state ok")
+	assert.Regexpf(t,
+		regexp.MustCompile(`^OK - [\d.]+ seconds response time on port 45666`),
+		string(res.BuildPluginOutput()),
+		"output matches",
+	)
+
+	StopTestAgent(t, snc)
+}