fix using arguments in aliased checks (#69)

Changes

@@ -1,5 +1,8 @@
 This file documents the revision history for the SNClient+ agent.
 
+next:
+         - fix using arguments in aliased checks (#69)
+
 0.15     Fri Dec 15 23:31:08 CET 2023
          - improve counter memory consumption
          - change internal wmi library

pkg/snclient/check_alias.go

@@ -1,6 +1,12 @@
 package snclient
 
-import "context"
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"pkg/utils"
+)
 
 type CheckAlias struct {
 	noCopy  noCopy
@@ -15,7 +21,7 @@ func (a *CheckAlias) Build() *CheckData {
 	}
 }
 
-func (a *CheckAlias) Check(ctx context.Context, snc *Agent, check *CheckData, _ []Argument) (*CheckResult, error) {
+func (a *CheckAlias) Check(ctx context.Context, snc *Agent, check *CheckData, _ []Argument) (res *CheckResult, err error) {
 	userArgs := check.rawArgs
 	var statusResult *CheckResult
 	switch {
@@ -30,9 +36,27 @@ func (a *CheckAlias) Check(ctx context.Context, snc *Agent, check *CheckData, _
 			Output: "Exception processing request: Request contained illegal characters (check the allow nasty characters option).",
 		}
 	default:
-		args := a.args
-		args = append(args, userArgs...)
-		statusResult = snc.runCheck(ctx, a.command, args)
+		cmdArgs := a.args
+		argStr := strings.Join(a.args, " ")
+		if strings.Contains(argStr, "$ARG") {
+			log.Debugf("command before macros expanded: %s %s", a.command, argStr)
+			macros := map[string]string{
+				"ARGS": strings.Join(userArgs, " "),
+			}
+			for i := range userArgs {
+				macros[fmt.Sprintf("ARG%d", i+1)] = check.rawArgs[i]
+			}
+
+			replacedStr := ReplaceRuntimeMacros(strings.Join(a.args, " "), macros)
+			cmdArgs = utils.Tokenize(replacedStr)
+			cmdArgs, err = utils.TrimQuotesAll(cmdArgs)
+			if err != nil {
+				return nil, fmt.Errorf("argument error: %s", err.Error())
+			}
+
+			log.Debugf("command after macros expanded: %s %s", a.command, replacedStr)
+		}
+		statusResult = snc.runCheck(ctx, a.command, cmdArgs)
 	}
 
 	statusResult.ParsePerformanceDataFromOutputCond(a.command, a.config)

pkg/snclient/check_alias_test.go

@@ -27,6 +27,14 @@ allow arguments = yes
 command = check_cpu warn=load=101 crit=load=102
 allow arguments = yes
 nasty characters = []{}
+
+[/settings/external scripts/alias/alias_dummy]
+command = check_dummy $ARG1$ "$ARG2$ $ARG3$"
+allow arguments = yes
+
+[/settings/external scripts/alias/alias_dummy2]
+command = check_dummy $ARGS$
+allow arguments = yes
 `
 	snc := StartTestAgent(t, config)
 
@@ -65,5 +73,15 @@ nasty characters = []{}
 	res = snc.RunCheck("alias_cpu4", []string{"filter=core!=$"})
 	assert.Equalf(t, CheckExitOK, res.State, "state OK")
 
+	// dummy check with arguments
+	res = snc.RunCheck("alias_dummy", []string{"0", "test 123", "456"})
+	assert.Equalf(t, CheckExitOK, res.State, "state OK")
+	assert.Equalf(t, "test 123 456", string(res.BuildPluginOutput()), "plugin output matches")
+
+	// dummy check with arguments
+	res = snc.RunCheck("alias_dummy2", []string{"0", "test 123", "456"})
+	assert.Equalf(t, CheckExitOK, res.State, "state OK")
+	assert.Equalf(t, "test 123 456", string(res.BuildPluginOutput()), "plugin output matches")
+
 	StopTestAgent(t, snc)
 }

pkg/snclient/task_external_scripts.go

@@ -140,7 +140,7 @@ func (e *ExternalScriptsHandler) registerAliases(conf *Config) error {
 		cmdConf := conf.Section(sectionName)
 		if command, ok := cmdConf.GetString("command"); ok {
 			f := utils.Tokenize(command)
-			log.Tracef("registered wrapped script: %s -> %s", name, command)
+			log.Tracef("registered alias script: %s -> %s", name, command)
 			AvailableChecks[name] = CheckEntry{name, func() CheckHandler { return &CheckAlias{command: f[0], args: f[1:], config: cmdConf} }}
 		} else {
 			return fmt.Errorf("missing command in alias script %s", name)