feat: refactor app in a separate package

internal/app/app.go

@@ -0,0 +1,35 @@
+package app
+
+import (
+	"github.com/miekg/dns"
+	"github.com/mr-karan/doggo/pkg/models"
+	"github.com/mr-karan/doggo/pkg/resolvers"
+	"github.com/sirupsen/logrus"
+)
+
+// App represents the structure for all app wide configuration.
+type App struct {
+	Logger       *logrus.Logger
+	Version      string
+	QueryFlags   models.QueryFlags
+	Questions    []dns.Question
+	Resolvers    []resolvers.Resolver
+	ResolverOpts resolvers.Options
+	Nameservers  []models.Nameserver
+}
+
+// NewApp initializes an instance of App which holds app wide configuration.
+func New(logger *logrus.Logger, buildVersion string) App {
+	app := App{
+		Logger:  logger,
+		Version: buildVersion,
+		QueryFlags: models.QueryFlags{
+			QNames:      []string{},
+			QTypes:      []string{},
+			QClasses:    []string{},
+			Nameservers: []string{},
+		},
+		Nameservers: []models.Nameserver{},
+	}
+	return app
+}