refactor: improve help handling (#2241)

Author: josedonizetti

cmd/tracee-ebpf/flags/cache.go

@@ -8,7 +8,7 @@ import (
 	"github.com/aquasecurity/tracee/pkg/events/queue"
 )
 
-func CacheHelp() string {
+func cacheHelp() string {
 	return `Select different cache types for the event pipeline queueing.
 Possible options:
 cache-type={none,mem}                              pick the appropriate cache type.

cmd/tracee-ebpf/flags/capabilities.go

@@ -16,7 +16,7 @@ const (
 	AddReqCapsFlag      = "add"
 )
 
-func CapabilitiesHelp() string {
+func capabilitiesHelp() string {
 	mainHelp := fmt.Sprintf(`Manage the capabilities and capabilities-related operations of tracee-ebpf
 Normally, tracee will drop all capabilities not required to its operations.
 

cmd/tracee-ebpf/flags/capture.go

@@ -9,7 +9,7 @@ import (
 	tracee "github.com/aquasecurity/tracee/pkg/ebpf"
 )
 
-func CaptureHelp() string {
+func captureHelp() string {
 	return `Capture artifacts that were written, executed or found to be suspicious.
 Captured artifacts will appear in the 'output-path' directory.
 Possible options:

cmd/tracee-ebpf/flags/containers.go

@@ -9,7 +9,7 @@ import (
 	"github.com/aquasecurity/tracee/pkg/containers/runtime"
 )
 
-func ContainersHelp() string {
+func containersHelp() string {
 	return `Select which container runtimes to connect to for container events enrichment.
 By default, if no flag is passed, tracee will automatically detect installed runtimes by going through known runtime socket paths.
 

cmd/tracee-ebpf/flags/filter.go

@@ -8,7 +8,7 @@ import (
 	"github.com/aquasecurity/tracee/pkg/filters"
 )
 
-func FilterHelp() string {
+func filterHelp() string {
 	return `Select which events to trace by defining trace expressions that operate on events or process metadata.
 Only events that match all trace expressions will be traced (trace flags are ANDed).
 The following types of expressions are supported:

cmd/tracee-ebpf/flags/help.go

@@ -0,0 +1,52 @@
+package flags
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/urfave/cli/v2"
+)
+
+func PrintAndExitIfHelp(ctx *cli.Context) {
+	keys := []string{
+		"crs",
+		"cache",
+		"capture",
+		"trace",
+		"output",
+		"caps",
+	}
+
+	for _, k := range keys {
+		stringSlice := ctx.StringSlice(k)
+		if checkIsHelp(stringSlice) {
+			fmt.Print(getHelpString(k))
+			os.Exit(0)
+		}
+	}
+}
+
+func checkIsHelp(s []string) bool {
+	if len(s) == 1 && s[0] == "help" {
+		return true
+	}
+	return false
+}
+
+func getHelpString(key string) string {
+	switch key {
+	case "crs":
+		return containersHelp()
+	case "cache":
+		return cacheHelp()
+	case "capture":
+		return captureHelp()
+	case "trace":
+		return filterHelp()
+	case "output":
+		return outputHelp()
+	case "caps":
+		return capabilitiesHelp()
+	}
+	return ""
+}

cmd/tracee-ebpf/flags/help_test.go

@@ -0,0 +1,29 @@
+package flags
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_checkIsHelp(t *testing.T) {
+	testCases := []struct {
+		testName string
+		input    []string
+		expected bool
+	}{
+		{"no flag", []string{""}, false},
+		{"help flag", []string{"help"}, true},
+		{"capture flag", []string{"capture"}, false},
+		{"output flag", []string{"output"}, false},
+		{"trace flag", []string{"trace"}, false},
+		{"multiple flags", []string{"help", "capture"}, false},
+	}
+
+	for _, testcase := range testCases {
+		t.Run(testcase.testName, func(t *testing.T) {
+			actual := checkIsHelp(testcase.input)
+			assert.Equal(t, testcase.expected, actual)
+		})
+	}
+}

cmd/tracee-ebpf/flags/output.go

@@ -10,7 +10,7 @@ import (
 	tracee "github.com/aquasecurity/tracee/pkg/ebpf"
 )
 
-func OutputHelp() string {
+func outputHelp() string {
 	return `Control how and where output is printed.
 Possible options:
 [format:]table                                     output events in table format

cmd/tracee-ebpf/main.go

@@ -38,6 +38,8 @@ func main() {
 				return cli.ShowAppHelp(c)
 			}
 
+			flags.PrintAndExitIfHelp(c)
+
 			if c.Bool("list") {
 				printList()
 				return nil
@@ -88,23 +90,13 @@ func main() {
 				ContainersEnrich:   enrich,
 			}
 
-			containerRuntimesSlice := c.StringSlice("crs")
-			if checkCommandIsHelp(containerRuntimesSlice) {
-				fmt.Print(flags.ContainersHelp())
-				return nil
-			}
-			sockets, err := flags.PrepareContainers(containerRuntimesSlice)
+			sockets, err := flags.PrepareContainers(c.StringSlice("crs"))
 			if err != nil {
 				return err
 			}
 			cfg.Sockets = sockets
 
-			cacheSlice := c.StringSlice("cache")
-			if checkCommandIsHelp(cacheSlice) {
-				fmt.Print(flags.CacheHelp())
-				return nil
-			}
-			cache, err := flags.PrepareCache(cacheSlice)
+			cache, err := flags.PrepareCache(c.StringSlice("cache"))
 			if err != nil {
 				return err
 			}
@@ -113,23 +105,13 @@ func main() {
 				logger.Debug("cache", "type", cfg.Cache.String())
 			}
 
-			captureSlice := c.StringSlice("capture")
-			if checkCommandIsHelp(captureSlice) {
-				fmt.Print(flags.CaptureHelp())
-				return nil
-			}
-			capture, err := flags.PrepareCapture(captureSlice)
+			capture, err := flags.PrepareCapture(c.StringSlice("capture"))
 			if err != nil {
 				return err
 			}
 			cfg.Capture = &capture
 
-			traceSlice := c.StringSlice("trace")
-			if checkCommandIsHelp(traceSlice) {
-				fmt.Print(flags.FilterHelp())
-				return nil
-			}
-			filter, err := flags.PrepareFilter(traceSlice)
+			filter, err := flags.PrepareFilter(c.StringSlice("trace"))
 			if err != nil {
 				return err
 			}
@@ -139,25 +121,15 @@ func main() {
 				(cfg.Filter.NewContFilter.Enabled() && cfg.Filter.NewContFilter.Value()) ||
 				cfg.Filter.ContIDFilter.Enabled()
 
-			outputSlice := c.StringSlice("output")
-			if checkCommandIsHelp(outputSlice) {
-				fmt.Print(flags.OutputHelp())
-				return nil
-			}
-			output, printerConfig, err := flags.PrepareOutput(outputSlice)
+			output, printerConfig, err := flags.PrepareOutput(c.StringSlice("output"))
 			if err != nil {
 				return err
 			}
 
 			printerConfig.ContainerMode = containerMode
 			cfg.Output = &output
 
-			capsCfgSlice := c.StringSlice("caps")
-			if checkCommandIsHelp(capsCfgSlice) {
-				fmt.Print(flags.CapabilitiesHelp())
-				return nil
-			}
-			capsCfg, err := flags.PrepareCapsConfig(capsCfgSlice)
+			capsCfg, err := flags.PrepareCapsConfig(c.StringSlice("caps"))
 			if err != nil {
 				return err
 			}
@@ -379,13 +351,6 @@ func main() {
 	}
 }
 
-func checkCommandIsHelp(s []string) bool {
-	if len(s) == 1 && s[0] == "help" {
-		return true
-	}
-	return false
-}
-
 func getFormattedEventParams(eventID events.ID) string {
 	evtDef, exists := events.Definitions.GetSafe(eventID)
 	if !exists {

cmd/tracee-ebpf/main_test.go

@@ -8,28 +8,6 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func Test_checkCommandIsHelp(t *testing.T) {
-	testCases := []struct {
-		testName string
-		input    []string
-		expected bool
-	}{
-		{"no flag", []string{""}, false},
-		{"help flag", []string{"help"}, true},
-		{"capture flag", []string{"capture"}, false},
-		{"output flag", []string{"output"}, false},
-		{"trace flag", []string{"trace"}, false},
-		{"multiple flags", []string{"help", "capture"}, false},
-	}
-
-	for _, testcase := range testCases {
-		t.Run(testcase.testName, func(t *testing.T) {
-			actual := checkCommandIsHelp(testcase.input)
-			assert.Equal(t, testcase.expected, actual)
-		})
-	}
-}
-
 func Test_getFormattedEventParams(t *testing.T) {
 	testCases := []struct {
 		input  events.ID