add testcases for cos and ubuntu to retrieve modules

pkg/util/metrics/system/common.go

@@ -19,7 +19,7 @@ import (
 )
 
 // ReadFile reads contents from a file and returns lines.
-func ReadFile(filename string) ([]string, error) {
+func ReadFileIntoLines(filename string) ([]string, error) {
 	file, err := os.Open(filename)
 	if err != nil {
 		return nil, err

pkg/util/metrics/system/module_stats.go

@@ -20,7 +20,9 @@ import (
 	"strings"
 )
 
-type ModuleStat struct {
+var modulesFilePath = "/proc/modules"
+
+type Module struct {
 	ModuleName  string `json:"moduleName"`
 	Instances   uint64 `json:"instances"`
 	Proprietary bool   `json:"proprietary"`
@@ -28,20 +30,19 @@ type ModuleStat struct {
 	Unsigned    bool   `json:"unsigned"`
 }
 
-func (d ModuleStat) String() string {
+func (d Module) String() string {
 	s, _ := json.Marshal(d)
 	return string(s)
 }
 
 // Module returns all the kernel modules and their
 // usage. It is read from cat /proc/modules.
-func Modules() ([]ModuleStat, error) {
+func Modules() ([]Module, error) {
-	filename := "/proc/modules"
+	lines, err := ReadFileIntoLines(modulesFilePath)
-	lines, err := ReadFile(filename)
 	if err != nil {
-		return nil, fmt.Errorf("Error reading the contents of %s: %s", filename, err)
+		return nil, fmt.Errorf("error reading the contents of %s: %s", modulesFilePath, err)
 	}
-	var result = make([]ModuleStat, 0, len(lines))
+	var result = make([]Module, 0, len(lines))
 
 	/* a line of /proc/modules has the following structure
 	  nf_nat 61440 2 xt_MASQUERADE,iptable_nat, Live 0x0000000000000000  (O)
@@ -58,28 +59,23 @@ func Modules() ([]ModuleStat, error) {
 		fields := strings.Fields(line)
 		moduleName := fields[0] // name of the module
 		numberOfInstances, err :=
-			strconv.ParseUint((fields[1]), 10, 64) // instances of the module are currently loaded
+			strconv.ParseUint((fields[2]), 10, 64) // instances of the module are currently loaded
 		if err != nil {
-			return nil, err
+			numberOfInstances = 0
 		}
 
-		var isProprietary = false
+		var module = Module{
-		var isOutofTree = false
+			ModuleName: moduleName,
-		var isUnsigned = false
+			Instances:  numberOfInstances,
+		}
 		// if the len of the fields is greater than 6, then the kernel taint state is available.
 		if len(fields) > 6 {
-			isProprietary = strings.Contains(fields[6], "P")
+			module.Proprietary = strings.Contains(fields[6], "P")
-			isOutofTree = strings.Contains(fields[6], "O")
+			module.OutOfTree = strings.Contains(fields[6], "O")
-			isUnsigned = strings.Contains(fields[6], "E")
+			module.Unsigned = strings.Contains(fields[6], "E")
 		}
-		var stats = ModuleStat{
+
-			ModuleName:  moduleName,
+		result = append(result, module)
-			Instances:   numberOfInstances,
-			Proprietary: isProprietary,
-			OutOfTree:   isOutofTree,
-			Unsigned:    isUnsigned,
-		}
-		result = append(result, stats)
 	}
 	return result, nil
 }

pkg/util/metrics/system/module_stats_test.go

@@ -21,17 +21,99 @@ import (
 )
 
 func TestModules(t *testing.T) {
-	modules, err := Modules()
+	testcases := []struct {
-	if err != nil {
+		name               string
-		t.Errorf("error %v", err)
+		fakeModuleFilePath string
+		expectedModules    []Module
+	}{
+		{
+			name:               "default_cos",
+			fakeModuleFilePath: "testdata/modules_cos.txt",
+			expectedModules: []Module{
+				{
+					ModuleName:  "crypto_simd",
+					Instances:   0x1,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "virtio_balloon",
+					Instances:   0x0,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "cryptd",
+					Instances:   0x1,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "loadpin_trigger",
+					Instances:   0x0,
+					Proprietary: false,
+					OutOfTree:   true,
+					Unsigned:    false,
+				},
+			},
+		},
+		{
+			name:               "default_ubuntu",
+			fakeModuleFilePath: "testdata/modules_ubuntu.txt",
+			expectedModules: []Module{
+				{
+					ModuleName:  "drm",
+					Instances:   0x0,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "virtio_rng",
+					Instances:   0x0,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "x_tables",
+					Instances:   0x1,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+				{
+					ModuleName:  "autofs4",
+					Instances:   0x2,
+					Proprietary: false,
+					OutOfTree:   false,
+					Unsigned:    false,
+				},
+			},
+		},
 	}
-	if modules == nil {
+	for _, test := range testcases {
-		t.Error("Error retrieving modules")
+		t.Run(test.name, func(t *testing.T) {
+			originalModuleFilePath := modulesFilePath
+			defer func() {
+				modulesFilePath = originalModuleFilePath
+			}()
+
+			modulesFilePath = test.fakeModuleFilePath
+			modules, err := Modules()
+			if err != nil {
+				t.Errorf("Unexpected error retrieving modules: %v\nModulesFilePath: %s\n", err, modulesFilePath)
+			}
+			assert.Equal(t, modules, test.expectedModules, "unpected modules retrieved: %v, expected: %v", modules, test.expectedModules)
+		})
 	}
 }
 
 func TestModuleStat_String(t *testing.T) {
-	v := ModuleStat{
+	v := Module{
 		ModuleName: "test",
 		Instances:  2,
 		OutOfTree:  false,
@@ -39,6 +121,6 @@ func TestModuleStat_String(t *testing.T) {
 	}
 	e := `{"moduleName":"test","instances":2,"proprietary":false,"outOfTree":false,"unsigned":false}`
 	assert.Equal(t,
-		e, fmt.Sprintf("%v", v), "ModuleStat string is invalid: %v", v)
+		e, fmt.Sprintf("%v", v), "Module string is invalid: %v", v)
 
 }

pkg/util/metrics/system/testdata/modules_cos.txt

@@ -0,0 +1,4 @@
+crypto_simd 16384 1 aesni_intel, Live 0x0000000000000000
+virtio_balloon 24576 0 - Live 0x0000000000000000
+cryptd 24576 1 crypto_simd, Live 0x0000000000000000
+loadpin_trigger 12288 0 [permanent], Live 0x0000000000000000 (O)

pkg/util/metrics/system/testdata/modules_ubuntu.txt

@@ -0,0 +1,4 @@
+drm 491520 0 - Live 0x0000000000000000
+virtio_rng 16384 0 - Live 0x0000000000000000
+x_tables 40960 1 ip_tables, Live 0x0000000000000000
+autofs4 45056 2 - Live 0x0000000000000000