dev: Set active source in ttnv3 command

Execute parent's persistent pre-run in subcommands spf13/cobra#252

cmd/ttnv3/application.go

@@ -23,8 +23,10 @@ import (
 
 var applicationsCmd = &cobra.Command{
 	Use:     "application [app-id] ...",
-	Aliases: []string{"applications", "app"},
 	Short:   "Export all devices of an application",
+	Aliases: []string{"applications", "app"},
+
+	PersistentPreRunE: commands.ExecuteParentPersistentPreRun,
 	Run: func(cmd *cobra.Command, args []string) {
 		commands.Export(cmd, args, func(s source.Source, item string) error {
 			return s.RangeDevices(item, export.FromContext(cmd.Context()).ExportDev)

cmd/ttnv3/devices.go

@@ -25,6 +25,8 @@ var devicesCmd = &cobra.Command{
 	Use:     "device [dev-id] ...",
 	Short:   "Export devices by DevEUI",
 	Aliases: []string{"end-devices", "end-device", "devices", "dev"},
+
+	PersistentPreRunE: commands.ExecuteParentPersistentPreRun,
 	RunE: func(cmd *cobra.Command, args []string) error {
 		return commands.Export(cmd, args, export.FromContext(cmd.Context()).ExportDev)
 	},

cmd/ttnv3/ttnv3.go

@@ -16,13 +16,22 @@ package ttnv3
 
 import (
 	"github.com/spf13/cobra"
+
+	"go.thethings.network/lorawan-stack-migrate/pkg/commands"
+	"go.thethings.network/lorawan-stack-migrate/pkg/source"
 )
 
 const sourceName = "ttnv3"
 
 // TTNv3Cmd represents the ttnv3 source.
 var TTNv3Cmd = &cobra.Command{
-	Use:          sourceName + " ...",
-	Short:        "Export devices from The Things Stack",
+	Use:   sourceName + " ...",
+	Short: "Export devices from The Things Stack",
+
 	SilenceUsage: true,
+	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+		source.RootConfig.Source = sourceName
+
+		return commands.ExecuteParentPersistentPreRun(cmd, args)
+	},
 }

pkg/commands/parent.go

@@ -0,0 +1,49 @@
+// Copyright © 2023 The Things Network Foundation, The Things Industries B.V.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package commands
+
+import "github.com/spf13/cobra"
+
+func ExecuteParentPersistentPreRun(cmd *cobra.Command, args []string) error {
+	if !cmd.HasParent() {
+		return nil
+	}
+	p := cmd.Parent()
+
+	if f := p.PersistentPreRunE; f != nil {
+		if err := f(p, args); err != nil {
+			return err
+		}
+	} else if f := p.PersistentPreRun; f != nil {
+		f(p, args)
+	}
+	return nil
+}
+
+func ExecuteParentPersistentPostRun(cmd *cobra.Command, args []string) error {
+	if !cmd.HasParent() {
+		return nil
+	}
+	p := cmd.Parent()
+
+	if f := p.PersistentPostRunE; f != nil {
+		if err := f(p, args); err != nil {
+			return err
+		}
+	} else if f := p.PersistentPostRun; f != nil {
+		f(p, args)
+	}
+	return nil
+}