Add --context flag

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- [#215](https://github.com/deviceinsight/kafkactl/pull/215) Add `--context` option to set command's context
 
 ## 5.3.0 - 2024-08-14
 ### Added

cmd/config/useContext.go

@@ -1,10 +1,7 @@
 package config
 
 import (
-	"sort"
-
 	"github.com/deviceinsight/kafkactl/v5/internal/global"
-
 	"github.com/deviceinsight/kafkactl/v5/internal/output"
 	"github.com/pkg/errors"
 
@@ -42,15 +39,7 @@ func newUseContextCmd() *cobra.Command {
 				return nil, cobra.ShellCompDirectiveNoFileComp
 			}
 
-			contextMap := viper.GetStringMap("contexts")
-			contexts := make([]string, 0, len(contextMap))
-			for k := range contextMap {
-				contexts = append(contexts, k)
-			}
-
-			sort.Strings(contexts)
-
-			return contexts, cobra.ShellCompDirectiveNoFileComp
+			return global.ListAvailableContexts(), cobra.ShellCompDirectiveNoFileComp
 		},
 	}
 

cmd/root.go

@@ -54,6 +54,14 @@ func NewKafkactlCommand(streams output.IOStreams) *cobra.Command {
 	rootCmd.PersistentFlags().StringVarP(&globalFlags.ConfigFile, "config-file", "C", "",
 		fmt.Sprintf("config file. default locations: %v", globalConfig.DefaultPaths()))
 	rootCmd.PersistentFlags().BoolVarP(&globalFlags.Verbose, "verbose", "V", false, "verbose output")
+	rootCmd.PersistentFlags().StringVar(&globalFlags.Context, "context", "", "The name of the context to use")
+
+	err := rootCmd.RegisterFlagCompletionFunc("context", func(_ *cobra.Command, _ []string, _ string) ([]string, cobra.ShellCompDirective) {
+		return global.ListAvailableContexts(), cobra.ShellCompDirectiveNoFileComp
+	})
+	if err != nil {
+		panic(err)
+	}
 
 	k8s.KafkaCtlVersion = Version
 

cmd/root_test.go

@@ -3,8 +3,11 @@ package cmd_test
 import (
 	"fmt"
 	"os"
+	"strings"
 	"testing"
 
+	"github.com/deviceinsight/kafkactl/v5/internal/output"
+
 	"github.com/deviceinsight/kafkactl/v5/internal/global"
 
 	"github.com/deviceinsight/kafkactl/v5/internal/testutil"
@@ -125,3 +128,53 @@ func TestEnvironmentVariableLoadingAliases(t *testing.T) {
 	testutil.AssertEquals(t, "WaitForAll", viper.GetString("contexts.default.producer.requiredAcks"))
 	testutil.AssertEquals(t, "1234", viper.GetString("contexts.default.producer.maxMessageBytes"))
 }
+
+func TestContextFlag(t *testing.T) {
+
+	testutil.StartUnitTest(t)
+
+	kafkaCtl := testutil.CreateKafkaCtlCommand()
+
+	if _, err := kafkaCtl.Execute("version", "--context", "sasl-user"); err != nil {
+		t.Fatalf("failed to execute command: %v", err)
+	}
+
+	testutil.AssertEquals(t, "sasl-user", global.GetCurrentContext())
+}
+
+func TestContextFlagProvidesUnknownContext(t *testing.T) {
+
+	testutil.StartUnitTest(t)
+
+	kafkaCtl := testutil.CreateKafkaCtlCommand()
+
+	if _, err := kafkaCtl.Execute("version", "--context", "unknown-context"); err != nil {
+		t.Fatalf("failed to execute command: %v", err)
+	}
+
+	var failError error
+
+	output.Fail = func(err error) {
+		failError = err
+	}
+
+	global.GetCurrentContext()
+
+	testutil.AssertErrorContains(t, "not a valid context: unknown-context", failError)
+}
+
+func TestContextFlagAutoCompletion(t *testing.T) {
+
+	testutil.StartUnitTest(t)
+
+	kafkaCtl := testutil.CreateKafkaCtlCommand()
+	kafkaCtl.Verbose = false
+
+	if _, err := kafkaCtl.Execute("__complete", "--context", ""); err != nil {
+		t.Fatalf("failed to execute command: %v", err)
+	}
+
+	outputLines := strings.Split(strings.TrimSpace(kafkaCtl.GetStdOut()), "\n")
+
+	testutil.AssertArraysEquals(t, []string{"default", "k8s-mock", "no-avro", "sasl-admin", "sasl-user"}, outputLines[:len(outputLines)-1])
+}

internal/global/config.go

@@ -2,9 +2,11 @@ package global
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
 	"runtime"
+	"sort"
 	"strings"
 
 	"github.com/deviceinsight/kafkactl/v5/internal/output"
@@ -13,6 +15,7 @@ import (
 
 type Flags struct {
 	ConfigFile string
+	Context    string
 	Verbose    bool
 }
 
@@ -51,7 +54,30 @@ func GetFlags() Flags {
 	return configInstance.flags
 }
 
+func ListAvailableContexts() []string {
+
+	var contexts []string
+	for k := range viper.GetStringMap("contexts") {
+		contexts = append(contexts, k)
+	}
+
+	sort.Strings(contexts)
+	return contexts
+}
+
 func GetCurrentContext() string {
+	var context = configInstance.Flags().Context
+	if context != "" {
+		contexts := viper.GetStringMap("contexts")
+
+		// check if it is an existing context
+		if _, ok := contexts[context]; !ok {
+			output.Fail(fmt.Errorf("not a valid context: %s", context))
+		}
+
+		return context
+	}
+
 	return configInstance.currentContext()
 }