Improve test coverage for cmd package (#53)

* add test for runServerCmd

* update NewDependencies test tp return err if dependencies are not valid

* return err if dependencies are not valid

* create new cobra command with SetupSignalHandler

* refactor server Start with SetupSignalHandler for testable code

* add test for root cmd

* refactor root cmd

* add test for setupSignalHandler

* implement SetupSignalHandler

* add newRunCmdWithOpts to rootCmd with SetupSignalHandler

* add test for LifeCycleHook

* refactor if-else statement

* remove signals package and import it from sigs.k8s.io/controller-runtime

* add version cmd to root

* remove TDD cycle comments

Author: ajatprabha

cmd/root.go

@@ -2,20 +2,24 @@ package cmd
 
 import (
 	"github.com/spf13/cobra"
+	"sigs.k8s.io/controller-runtime/pkg/manager/signals"
 )
 
-var rootCmd = &cobra.Command{
-	Use:   "darkroom",
-	Short: "Darkroom is an Image Proxy on your image source",
+// newRootCmd represents the base command when called without any subcommands.
+func newRootCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "darkroom",
+		Short: "Darkroom is an Image Proxy on your image source",
+	}
+	cmd.AddCommand(newRunCmdWithOpts(runCmdOpts{
+		SetupSignalHandler: signals.SetupSignalHandler,
+	}))
+	cmd.AddCommand(newVersionCmd())
+	return cmd
 }
 
-func init() {
-	rootCmd.AddCommand(serverCmd)
-	rootCmd.AddCommand(newVersionCmd())
-}
-
-// Run function lets you run the commands
-func Run(args []string) error {
-	rootCmd.SetArgs(args)
-	return rootCmd.Execute()
+// Execute adds all child commands to the root command and sets flags appropriately.
+// This is called by main.main(). It only needs to happen once to the rootCmd.
+func Execute() error {
+	return newRootCmd().Execute()
 }

cmd/root_test.go

@@ -0,0 +1,11 @@
+package cmd
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestRootCmd(t *testing.T) {
+	err := Execute()
+	assert.NoError(t, err)
+}

cmd/server.go

@@ -1,30 +1,36 @@
 package cmd
 
 import (
-	"github.com/gojek/darkroom/pkg/logger"
 	"github.com/gojek/darkroom/pkg/router"
 	"github.com/gojek/darkroom/pkg/server"
 	"github.com/gojek/darkroom/pkg/service"
 	"github.com/spf13/cobra"
 )
 
-var serverCmd = &cobra.Command{
-	Use:   "server",
-	Short: "Start the app server",
-	Run:   serverCmdF,
+type runCmdOpts struct {
+	SetupSignalHandler func() (stopCh <-chan struct{})
 }
 
-func serverCmdF(cmd *cobra.Command, args []string) {
-	defer func() {
-		if e := recover(); e != nil {
-			logger.Errorf("failed to start the app due to error: %s", e)
-		}
-	}()
-	startServer()
-}
-
-func startServer() {
-	handler := router.NewRouter(service.NewDependencies())
-	s := server.NewServer(server.WithHandler(handler))
-	s.Start()
+func newRunCmdWithOpts(opts runCmdOpts) *cobra.Command {
+	args := struct {
+		port int
+	}{}
+	cmd := &cobra.Command{
+		Use:   "server",
+		Short: "Start the app server",
+		RunE: func(cmd *cobra.Command, _ []string) error {
+			deps, err := service.NewDependencies()
+			if err != nil {
+				return err
+			}
+			handler := router.NewRouter(deps)
+			s := server.NewServer(server.Options{
+				Handler: handler,
+				Port:    args.port,
+			})
+			return s.Start(opts.SetupSignalHandler())
+		},
+	}
+	cmd.PersistentFlags().IntVarP(&args.port, "port", "p", 3000, "server port")
+	return cmd
 }

cmd/server_test.go

@@ -0,0 +1,92 @@
+package cmd
+
+import (
+	"fmt"
+	"github.com/gojek/darkroom/pkg/config"
+	"github.com/stretchr/testify/assert"
+	"net/http"
+	"testing"
+	"time"
+)
+
+func TestRunServer(t *testing.T) {
+	errCh := make(chan error)
+	stopCh := make(chan struct{})
+	diagnosticsPort := 9999
+	v := config.Viper()
+	v.Set("source.kind", "WebFolder")
+	v.Set("source.baseURL", "https://example.com/path/to/folder")
+	config.Update()
+
+	cmd := newRunCmdWithOpts(runCmdOpts{
+		SetupSignalHandler: func() <-chan struct{} {
+			return stopCh
+		},
+	})
+	cmd.SetArgs([]string{"-p", fmt.Sprintf("%d", diagnosticsPort)})
+
+	go func() {
+		defer close(errCh)
+		errCh <- cmd.Execute()
+	}()
+
+	assert.True(t, assert.Eventually(t, func() bool {
+		resp, err := http.Get(fmt.Sprintf("http://localhost:%d/ping", diagnosticsPort))
+		if err != nil {
+			return false
+		}
+		defer func() {
+			_ = resp.Body.Close()
+		}()
+		return resp.StatusCode == http.StatusOK
+	}, 5*time.Second, 100*time.Millisecond), "failed to run server")
+
+	close(stopCh)
+
+	assert.NoError(t, <-errCh)
+}
+
+func TestRunServerWithInvalidPort(t *testing.T) {
+	errCh := make(chan error)
+	stopCh := make(chan struct{})
+	v := config.Viper()
+	v.Set("source.kind", "WebFolder")
+	v.Set("source.baseURL", "https://example.com/path/to/folder")
+	config.Update()
+
+	cmd := newRunCmdWithOpts(runCmdOpts{
+		SetupSignalHandler: func() <-chan struct{} {
+			return stopCh
+		},
+	})
+	cmd.SetArgs([]string{"-p", fmt.Sprintf("%d", -9000)})
+
+	go func() {
+		defer close(errCh)
+		errCh <- cmd.Execute()
+	}()
+
+	assert.Error(t, <-errCh)
+}
+
+func TestRunServerWithInvalidDependencies(t *testing.T) {
+	errCh := make(chan error)
+	stopCh := make(chan struct{})
+	v := config.Viper()
+	v.Set("source.kind", "")
+	v.Set("source.baseURL", "")
+	config.Update()
+
+	cmd := newRunCmdWithOpts(runCmdOpts{
+		SetupSignalHandler: func() <-chan struct{} {
+			return stopCh
+		},
+	})
+
+	go func() {
+		defer close(errCh)
+		errCh <- cmd.Execute()
+	}()
+
+	assert.EqualError(t, <-errCh, "handler dependencies are not valid")
+}

go.mod

@@ -18,14 +18,10 @@ require (
 	github.com/rcrowley/go-metrics v0.0.0-20190706150252-9beb055b7962 // indirect
 	github.com/smartystreets/assertions v1.0.0 // indirect
 	github.com/smartystreets/goconvey v0.0.0-20190710185942-9d28bd7c0945 // indirect
-	github.com/spf13/afero v1.2.2 // indirect
 	github.com/spf13/cobra v0.0.5
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/viper v1.4.0
-	github.com/stretchr/objx v0.2.0 // indirect
-	github.com/stretchr/testify v1.3.0
+	github.com/stretchr/testify v1.6.1
 	go.uber.org/zap v1.10.0
-	golang.org/x/net v0.0.0-20190628185345-da137c7871d7 // indirect
-	golang.org/x/sys v0.0.0-20190712062909-fae7ac547cb7 // indirect
-	golang.org/x/text v0.3.2 // indirect
+	sigs.k8s.io/controller-runtime v0.6.1
 )