feat(cli): default command and global init functionality

pkg/cli/cli.go

@@ -4,12 +4,14 @@ import (
 	"github.com/conplementag/cops-hq/internal"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
+	"os"
 )
 
 type cli struct {
-	programName string
-	version     string
-	rootCmd     *cobra.Command
+	programName    string
+	version        string
+	rootCmd        *cobra.Command
+	defaultCommand string
 }
 
 func (cli *cli) AddBaseCommand(use string, shortInfo string, longDescription string, runFunction func()) Command {
@@ -48,10 +50,39 @@ func (cli *cli) AddBaseCommand(use string, shortInfo string, longDescription str
 }
 
 func (cli *cli) Run() error {
+	if cli.defaultCommand != "" {
+		rootCommand := cli.GetRootCommand()
+		registeredCommands := rootCommand.Commands()
+
+		var isCommandSet = false
+		for _, a := range registeredCommands {
+			for _, b := range os.Args[1:] {
+				if a.Name() == b {
+					isCommandSet = true
+					break
+				}
+			}
+		}
+
+		// if no command set on the command line, use the default command by extending the existing command line args
+		if !isCommandSet {
+			args := append([]string{cli.defaultCommand}, os.Args[1:]...)
+			rootCommand.SetArgs(args)
+		}
+	}
+
 	err := cli.rootCmd.Execute()
 	return internal.ReturnErrorOrPanic(err)
 }
 
 func (cli *cli) GetRootCommand() *cobra.Command {
 	return cli.rootCmd
 }
+
+func (cli *cli) OnInitialize(initFunction func()) {
+	cobra.OnInitialize(initFunction)
+}
+
+func (cli *cli) SetDefaultCommand(command string) {
+	cli.defaultCommand = command
+}

pkg/cli/cli_test.go

@@ -115,7 +115,6 @@ func Test_PersistentParametersAreAvailableThroughViperInSubcommands(t *testing.T
 
 func Test_ParametersFromDifferentCommandsShouldNotOverwriteEachOtherInViper(t *testing.T) {
 	// Arrange
-
 	cli := New("myprog", "0.0.1")
 
 	// Act
@@ -140,3 +139,61 @@ func Test_ParametersFromDifferentCommandsShouldNotOverwriteEachOtherInViper(t *t
 	assert.Equal(t, "johndoe", viper.GetString("my-arg"))
 	assert.Equal(t, true, viper.GetBool("truth"))
 }
+
+func Test_DefaultCommands(t *testing.T) {
+	// Arrange
+	cli := New("myprog", "0.0.1")
+	cli.SetDefaultCommand("first")
+
+	wasCalled := false
+
+	cli.AddBaseCommand("first", "Simple test command 1", "big description", func() {
+		wasCalled = true
+	})
+	cli.AddBaseCommand("second", "Simple test command 2", "big description", func() {})
+
+	// Act
+	testing_utils.PrepareCommandForTesting(cli.GetRootCommand(), "") // intentionally no args, to test the default was called
+	cli.Run()
+
+	// Assert
+	assert.True(t, wasCalled)
+}
+
+func Test_InitializerFunctionCalledWhenCommandExecuted(t *testing.T) {
+	// Arrange
+	cli := New("myprog", "0.0.1")
+	wasCalled := false
+
+	cli.OnInitialize(func() {
+		wasCalled = true
+	})
+
+	// Act
+	cli.AddBaseCommand("first", "Simple test command 1", "big description", nil)
+
+	testing_utils.PrepareCommandForTesting(cli.GetRootCommand(), "first")
+	cli.Run()
+
+	// Assert
+	assert.True(t, wasCalled)
+}
+
+func Test_InitializerFunctionNotCalledWhenNoCommandMatching(t *testing.T) {
+	// Arrange
+	cli := New("myprog", "0.0.1")
+	wasCalled := false
+
+	cli.OnInitialize(func() {
+		wasCalled = true
+	})
+
+	// Act
+	cli.AddBaseCommand("first", "Simple test command 1", "big description", nil)
+
+	testing_utils.PrepareCommandForTesting(cli.GetRootCommand(), "non-existing")
+	cli.Run()
+
+	// Assert
+	assert.False(t, wasCalled)
+}

pkg/cli/factory.go

@@ -18,6 +18,12 @@ type Cli interface {
 	// GetRootCommand returns the root top level command, directly as cobra.Command which is the library used
 	// under the hood.
 	GetRootCommand() *cobra.Command
+
+	// OnInitialize sets the passed function to be run when each command is called. Consider this like a global initializer
+	// hook.
+	OnInitialize(initFunction func())
+
+	SetDefaultCommand(command string)
 }
 
 // New creates a new Cli instance