helper functions added

helpers.go

@@ -0,0 +1,43 @@
+package systemctl
+
+import (
+	"context"
+	"strconv"
+	"time"
+
+	"github.com/taigrr/systemctl/properties"
+)
+
+const dateFormat = "Mon 2006-01-02 15:04:05 MST"
+
+// Get start time of a service (`systemctl show [unit] --property ExecMainStartTimestamp`) as a `Time` type
+func GetStartTime(ctx context.Context, unit string, opts Options) (time.Time, error) {
+	value, err := Show(ctx, unit, properties.ExecMainStartTimestamp, opts)
+
+	if err != nil {
+		return time.Unix(0, 0), err
+	}
+	// ExecMainStartTimestamp returns an empty string if the unit is not running
+	if value == "" {
+		return time.Unix(0, 0), ErrUnitNotRunning
+	}
+	return time.Parse(dateFormat, value)
+}
+
+// Get current memory in bytes (`systemctl show [unit] --property MemoryCurrent`) an an int
+func GetMemoryUsage(ctx context.Context, unit string, opts Options) (int, error) {
+	value, err := Show(ctx, unit, properties.MemoryCurrent, opts)
+	if err != nil {
+		return -1, err
+	}
+	return strconv.Atoi(value)
+}
+
+// Get the PID of the main process (`systemctl show [unit] --property MainPID`) as an int
+func GetPID(ctx context.Context, unit string, opts Options) (int, error) {
+	value, err := Show(ctx, unit, properties.MainPID, opts)
+	if err != nil {
+		return -1, err
+	}
+	return strconv.Atoi(value)
+}