test: make service-dependent tests portable

helpers_test.go

@@ -21,6 +21,7 @@ func TestGetStartTime(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping in short mode")
 	}
+	readOnlySystemUnit := systemTestUnit(t)
 	testCases := []struct {
 		unit      string
 		err       error
@@ -33,16 +34,16 @@ func TestGetStartTime(t *testing.T) {
 		// try existing unit in user mode as user
 		{"syncthing", ErrUnitNotActive, Options{UserMode: true}, true},
 		// try existing unit in system mode as user
-		{"nginx", nil, Options{UserMode: false}, true},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, true},
 
 		// Run these tests only as a superuser
 
 		// try nonexistant unit in system mode as system
 		{"nonexistant", ErrUnitNotActive, Options{UserMode: false}, false},
 		// try existing unit in system mode as system
-		{"nginx", ErrBusFailure, Options{UserMode: true}, false},
+		{readOnlySystemUnit, ErrBusFailure, Options{UserMode: true}, false},
 		// try existing unit in system mode as system
-		{"nginx", nil, Options{UserMode: false}, false},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, false},
 	}
 	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 	defer cancel()
@@ -94,6 +95,7 @@ func TestGetStartTime(t *testing.T) {
 }
 
 func TestGetNumRestarts(t *testing.T) {
+	readOnlySystemUnit := systemTestUnit(t)
 	type testCase struct {
 		unit      string
 		err       error
@@ -108,16 +110,16 @@ func TestGetNumRestarts(t *testing.T) {
 		// try existing unit in user mode as user (loaded, so NRestarts=0 is valid)
 		{"syncthing", nil, Options{UserMode: true}, true},
 		// try existing unit in system mode as user
-		{"nginx", nil, Options{UserMode: false}, true},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, true},
 
 		// Run these tests only as a superuser
 
 		// try nonexistant unit in system mode as system
 		{"nonexistant", ErrValueNotSet, Options{UserMode: false}, false},
 		// try existing unit in system mode as system
-		{"nginx", ErrBusFailure, Options{UserMode: true}, false},
+		{readOnlySystemUnit, ErrBusFailure, Options{UserMode: true}, false},
 		// try existing unit in system mode as system
-		{"nginx", nil, Options{UserMode: false}, false},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, false},
 	}
 	for _, tc := range testCases {
 		func(tc testCase) {
@@ -177,6 +179,7 @@ func TestGetNumRestarts(t *testing.T) {
 }
 
 func TestGetMemoryUsage(t *testing.T) {
+	readOnlySystemUnit := systemTestUnit(t)
 	type testCase struct {
 		unit      string
 		err       error
@@ -191,16 +194,16 @@ func TestGetMemoryUsage(t *testing.T) {
 		// try existing unit in user mode as user
 		{"syncthing", ErrValueNotSet, Options{UserMode: true}, true},
 		// try existing unit in system mode as user
-		{"nginx", nil, Options{UserMode: false}, true},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, true},
 
 		// Run these tests only as a superuser
 
 		// try nonexistant unit in system mode as system
 		{"nonexistant", ErrValueNotSet, Options{UserMode: false}, false},
 		// try existing unit in system mode as system
-		{"nginx", ErrBusFailure, Options{UserMode: true}, false},
+		{readOnlySystemUnit, ErrBusFailure, Options{UserMode: true}, false},
 		// try existing unit in system mode as system
-		{"nginx", nil, Options{UserMode: false}, false},
+		{readOnlySystemUnit, nil, Options{UserMode: false}, false},
 	}
 	for _, tc := range testCases {
 		func(tc testCase) {
@@ -224,9 +227,9 @@ func TestGetMemoryUsage(t *testing.T) {
 	t.Run("prove memory usage values change across services", func(t *testing.T) {
 		ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
 		defer cancel()
-		bytes, err := GetMemoryUsage(ctx, "nginx", Options{UserMode: false})
+		bytes, err := GetMemoryUsage(ctx, readOnlySystemUnit, Options{UserMode: false})
 		if err != nil {
-			t.Errorf("issue getting memory usage of nginx: %v", err)
+			t.Errorf("issue getting memory usage of %s: %v", readOnlySystemUnit, err)
 		}
 		secondBytes, err := GetMemoryUsage(ctx, "user.slice", Options{UserMode: false})
 		if err != nil {

systemctl_test.go

@@ -367,6 +367,7 @@ func TestRestart(t *testing.T) {
 	unit := "nginx"
 	userMode := false
 	if userString != "root" && userString != "system" {
+		t.Skip("skipping non-root lifecycle test without a portable controllable user unit")
 		userMode = true
 		unit = "syncthing"
 	}
@@ -406,7 +407,7 @@ func TestShow(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping test in short mode.")
 	}
-	unit := "nginx"
+	unit := systemTestUnit(t)
 	opts := Options{
 		UserMode: false,
 	}
@@ -429,6 +430,7 @@ func TestStart(t *testing.T) {
 	unit := "nginx"
 	userMode := false
 	if userString != "root" && userString != "system" {
+		t.Skip("skipping non-root lifecycle test without a portable controllable user unit")
 		userMode = true
 		unit = "syncthing"
 	}
@@ -461,7 +463,7 @@ func TestStart(t *testing.T) {
 }
 
 func TestStatus(t *testing.T) {
-	unit := "nginx"
+	unit := systemTestUnit(t)
 	userMode := false
 	opts := Options{UserMode: userMode}
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -476,6 +478,7 @@ func TestStop(t *testing.T) {
 	unit := "nginx"
 	userMode := false
 	if userString != "root" && userString != "system" {
+		t.Skip("skipping non-root lifecycle test without a portable controllable user unit")
 		userMode = true
 		unit = "syncthing"
 	}

test_units_test.go

@@ -0,0 +1,43 @@
+package systemctl
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/taigrr/systemctl/properties"
+)
+
+func systemTestUnit(t *testing.T) string {
+	t.Helper()
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	units, err := GetUnits(ctx, Options{UserMode: false})
+	if err != nil {
+		t.Fatalf("get system units: %v", err)
+	}
+	for _, unit := range units {
+		if unit.Active != "active" || unit.Sub != "running" || !strings.HasSuffix(unit.Name, ".service") {
+			continue
+		}
+		name := strings.TrimSuffix(unit.Name, ".service")
+		startTime, err := Show(ctx, name, properties.ExecMainStartTimestamp, Options{UserMode: false})
+		if err != nil || startTime == "" {
+			continue
+		}
+		restarts, err := Show(ctx, name, properties.NRestarts, Options{UserMode: false})
+		if err != nil || restarts == "" || restarts == "[not set]" {
+			continue
+		}
+		memory, err := Show(ctx, name, properties.MemoryCurrent, Options{UserMode: false})
+		if err != nil || memory == "" || memory == "[not set]" {
+			continue
+		}
+		return name
+	}
+
+	t.Skip("no readable active system service found for read-only tests")
+	return ""
+}