Update Go version and dependencies; add test cases for merging duplic… (#6)

* Update Go version and dependencies; add test cases for merging duplicated contexts, clusters, and users

* Update GitHub Actions workflows to use latest action versions

* formatted

* Refactor validation functions to export them and add unit tests for parsing and validation

* Fix missing newline at end of file in main_test.go

* Update README and main.go for improved CLI tool description and argument handling

Author: btungut

.github/workflows/ci.yml

@@ -11,12 +11,12 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup Go
-      uses: actions/setup-go@v3
+      uses: actions/setup-go@v5
       with:
-        go-version: 1.19
+        go-version: 1.23.6
         cache: true
         cache-dependency-path: go.sum
 
@@ -30,7 +30,7 @@ jobs:
       run: go mod tidy && git diff --no-patch --exit-code
 
     - name: Build with Goreleaser
-      uses: goreleaser/goreleaser-action@v2
+      uses: goreleaser/goreleaser-action@v6
       with:
         version: latest
         args: release --snapshot --clean
@@ -60,7 +60,7 @@ jobs:
         thresholds: '50 75'
 
     - name: Upload Go test results
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: go-test-coverage-report
         path: coverage.html

.github/workflows/release.yml

@@ -11,21 +11,21 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
 
     - run: git fetch --force --tags
 
     - name: Setup Go
-      uses: actions/setup-go@v3
+      uses: actions/setup-go@v5
       with:
-        go-version: 1.19
+        go-version: 1.23.6
         cache: true
         cache-dependency-path: go.sum
 
     - name: GoReleaser
-      uses: goreleaser/goreleaser-action@v4
+      uses: goreleaser/goreleaser-action@v6
       with:
         version: latest
         args: release --clean

.goreleaser.yaml

@@ -21,4 +21,4 @@ changelog:
   filters:
     exclude:
       - '^docs:'
-      - '^test:'
+      - '^test:'

README.md

@@ -5,11 +5,19 @@
 ![build](https://img.shields.io/github/actions/workflow/status/btungut/kubeconfig-merge/ci.yml?branch=master)
 ![go](https://img.shields.io/github/go-mod/go-version/btungut/kubeconfig-merge)
 
-## Why is it developed?
-If you are someone who works with a significant number of Kubernetes clusters, dealing with `kubecontext` in a manual way can be **boring** and also **result in problems**.
-In addition to that, I am currently working with more than 20 customers, which results in an average of five clusters per customer.
+# 🌟 kubeconfig-merge
 
-## Install
+`kubeconfig-merge` is a lightweight and efficient CLI tool designed to **merge multiple Kubernetes `kubeconfig` files** into a single, well-structured configuration. It ensures that the resulting configuration is clean, free of conflicts, and compatible with `kubectl` and other Kubernetes clients.
+
+## 🚀 Features
+
+✔ **Merge multiple `kubeconfig` files** into one unified configuration  
+✔ **Preserve existing contexts, clusters, and users** without conflicts  
+✔ **Ensure a clean and well-structured config file**  
+✔ **Works seamlessly with `kubectl` and Kubernetes clients**  
+✔ **Lightweight, fast, and easy to use**  
+
+## 📌 Installation
 
 ### Install on Linux
 
@@ -25,7 +33,6 @@ The following instruction list covers all of the Linux distributions (Ubuntu, De
         FILENAME="kubeconfig-merge_${OS}_${ARCH}" &&
         curl -fsSLO "https://github.com/btungut/kubeconfig-merge/releases/latest/download/${FILENAME}" &&
         sudo rm -rf "$EXEC_PATH" && sudo cp "${FILENAME}" "$EXEC_PATH" && sudo chmod +x "$EXEC_PATH"
-)
 ```
 
 ### Install on Windows
@@ -34,26 +41,16 @@ TBD
 
 ## Arguments
 
-| Argument     | Description                                                                | Default                                        |
-|--------------|----------------------------------------------------------------------------|------------------------------------------------|
-| file       | The additional kubeconfig file | *Required* |
-| kubeconfig | The kubeconfig file which to be append into        | `KUBECONFIG` env variable, or `~/.kube/config` |
-| name       | Context, cluster and user name of new entries                              | File name of `--file`|
+| Argument   | Type    | Description                                     | Default                                        |
+| ---------- | ------- | ----------------------------------------------- | ---------------------------------------------- |
+| kubeconfig | string  | The kubeconfig file which to be append into     | `KUBECONFIG` env variable, or `~/.kube/config` |
+| file       | string  | To be appended kubeconfig file                  | **Required**                                   |
+| override   | boolean | Use file name for the cluster, context and user | Optional                                       |
 
-## Examples
 
----
-### `./kubeconfig-merge --file valid-default-cluster.yaml`
-
-![kubeconfig-merge without name](.assets/kubeconfig-merge-01.png)
+## Examples
 
-<br/>
 
----
-
-### `./kubeconfig-merge --file valid-default-cluster.yaml --name foo`
-![kubeconfig-merge with name](.assets/kubeconfig-merge-02.png)
+### `./kubeconfig-merge --file valid-default-cluster.yaml`
 
-## Contributors
-[Ohki Nozomu](https://github.com/ohkinozomu)
- 
+![kubeconfig-merge without name](.assets/kubeconfig-merge-01.png)

go.mod

@@ -1,10 +1,10 @@
 module github.com/btungut/kubeconfig-merge
 
-go 1.19
+go 1.23.6
 
 require (
-	github.com/google/uuid v1.3.0
-	github.com/stretchr/testify v1.8.1
+	github.com/google/uuid v1.6.0
+	github.com/stretchr/testify v1.10.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 

go.sum

@@ -1,19 +1,12 @@
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
-github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
-github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
-github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
-github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
-github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

main.go

@@ -56,7 +56,14 @@ type KubectlClusterWithName struct {
 
 const KUBECONFIG_ENV = "KUBECONFIG"
 const KUBECONFIG_ENV_KEY = "$KUBECONFIG"
-const KUBECONFIG_DEFAULT_PATH = "~/.kube/config"
+
+var KUBECONFIG_DEFAULT_PATH = func() string {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		log.Panic(err)
+	}
+	return filepath.Join(home, ".kube", "config")
+}()
 
 func ParseKubeConfig(path string) (*KubectlConfig, error) {
 
@@ -74,7 +81,7 @@ func ParseKubeConfig(path string) (*KubectlConfig, error) {
 	return &kubeConfig, nil
 }
 
-func validate(toBeAppend KubectlConfig, kubectlConfig KubectlConfig, name string) error {
+func ValidateOnlyOneContext(toBeAppend KubectlConfig, kubectlConfig KubectlConfig) error {
 
 	if len(toBeAppend.Clusters) != 1 {
 		return errors.New("only one cluster can be merged into original kubeconfig")
@@ -88,49 +95,91 @@ func validate(toBeAppend KubectlConfig, kubectlConfig KubectlConfig, name string
 		return errors.New("only one context can be merged into original kubeconfig")
 	}
 
-	for _, v := range kubectlConfig.Clusters {
-		if strings.EqualFold(v.Name, name) {
-			return fmt.Errorf("a cluster entry with %s already exists in kubeconfig, merge failed", name)
+	return nil
+}
+
+func ValidateDuplication(toBeAppend KubectlConfig, kubectlConfig KubectlConfig) error {
+
+	for _, v1 := range kubectlConfig.Clusters {
+		for _, v2 := range toBeAppend.Clusters {
+			if strings.EqualFold(v1.Name, v2.Name) {
+				return fmt.Errorf("a cluster entry with %s already exists in kubeconfig, merge failed", v1.Name)
+			}
 		}
 	}
 
-	for _, v := range kubectlConfig.Contexts {
-		if strings.EqualFold(v.Name, name) {
-			return fmt.Errorf("a context entry with %s already exists in kubeconfig, merge failed", name)
+	for _, v1 := range kubectlConfig.Users {
+		for _, v2 := range toBeAppend.Users {
+			if strings.EqualFold(v1.Name, v2.Name) {
+				return fmt.Errorf("a user entry with %s already exists in kubeconfig, merge failed", v1.Name)
+			}
 		}
 	}
 
-	for _, v := range kubectlConfig.Users {
-		if strings.EqualFold(v.Name, name) {
-			return fmt.Errorf("a user entry with %s already exists in kubeconfig, merge failed", name)
+	for _, v1 := range kubectlConfig.Contexts {
+		for _, v2 := range toBeAppend.Contexts {
+			if strings.EqualFold(v1.Name, v2.Name) {
+				return fmt.Errorf("a context entry with %s already exists in kubeconfig, merge failed", v1.Name)
+			}
 		}
 	}
 
 	return nil
 }
 
-func Merge(kubeConfig KubectlConfig, toBeAppend KubectlConfig, name, toBeAppendFileName string) (*KubectlConfig, error) {
+func Merge(kubeConfig KubectlConfig, toBeAppend KubectlConfig, name string, override bool) (*KubectlConfig, error) {
 
-	var newName = toBeAppendFileName
-	if len(name) > 0 {
-		newName = name
+	var err = ValidateOnlyOneContext(toBeAppend, kubeConfig)
+	if err != nil {
+		return nil, err
 	}
 
-	var err = validate(toBeAppend, kubeConfig, toBeAppendFileName)
+	toBeAppend.Clusters[0].Name = name
+	toBeAppend.Users[0].Name = name
+	toBeAppend.Contexts[0].Name = name
+	toBeAppend.Contexts[0].Context.Cluster = name
+	toBeAppend.Contexts[0].Context.User = name
+
+	var needOverride = false
+	err = ValidateDuplication(toBeAppend, kubeConfig)
 	if err != nil {
-		return nil, err
+		if !override {
+			return nil, err
+		}
+		needOverride = true
+	}
+
+	if needOverride {
+		// remove the existing cluster, user and context
+		for i, v := range kubeConfig.Clusters {
+			if strings.EqualFold(v.Name, name) {
+				kubeConfig.Clusters = append(kubeConfig.Clusters[:i], kubeConfig.Clusters[i+1:]...)
+				break
+			}
+		}
+
+		for i, v := range kubeConfig.Users {
+			if strings.EqualFold(v.Name, name) {
+				kubeConfig.Users = append(kubeConfig.Users[:i], kubeConfig.Users[i+1:]...)
+				break
+			}
+		}
+
+		for i, v := range kubeConfig.Contexts {
+			if strings.EqualFold(v.Name, name) {
+				kubeConfig.Contexts = append(kubeConfig.Contexts[:i], kubeConfig.Contexts[i+1:]...)
+				break
+			}
+		}
+
+		fmt.Printf("Cluster, context and user with '%s' name is removed because of override flag\n", name)
 	}
 
-	toBeAppend.Clusters[0].Name = newName
-	toBeAppend.Users[0].Name = newName
-	toBeAppend.Contexts[0].Name = newName
-	toBeAppend.Contexts[0].Context.Cluster = newName
-	toBeAppend.Contexts[0].Context.User = newName
 	kubeConfig.Clusters = append(kubeConfig.Clusters, toBeAppend.Clusters[0])
 	kubeConfig.Users = append(kubeConfig.Users, toBeAppend.Users[0])
 	kubeConfig.Contexts = append(kubeConfig.Contexts, toBeAppend.Contexts[0])
 
-	fmt.Printf("Cluster, context and user will be added with '%s' name\n", newName)
+	fmt.Printf("Cluster, context and user will be added with '%s' name\n", name)
 
 	return &kubeConfig, nil
 }
@@ -156,7 +205,7 @@ func getKubeConfigPath(passedValue string) string {
 func main() {
 	kubeConfigPtr := flag.String("kubeconfig", "", fmt.Sprintf("path to the kubeconfig file (defaults '%s' or '%s')", KUBECONFIG_ENV_KEY, KUBECONFIG_DEFAULT_PATH))
 	filePtr := flag.String("file", "", "path to the yaml file that to be append into kubeconfig")
-	namePtr := flag.String("name", "", "Replaces the name of context, user and cluster (default file name of --file argument)")
+	overridePtr := flag.Bool("override", false, "Override the existing context, user and cluster with the file name, or the fields in the file will be used")
 	flag.Parse()
 
 	var kubeConfigPath = getKubeConfigPath(*kubeConfigPtr)
@@ -165,14 +214,19 @@ func main() {
 	if err != nil {
 		log.Panic(err)
 	}
+	if filepath.Ext(*filePtr) == "" {
+		log.Panic("the file specified by --file must have a valid extension")
+	}
 
 	toBeAppend, err := ParseKubeConfig(*filePtr)
 	if err != nil {
 		log.Panic(err)
 	}
 
 	var fileName = filepath.Base(*filePtr)
-	result, err := Merge(*kubeConfig, *toBeAppend, *namePtr, fileName[:len(fileName)-len(filepath.Ext(fileName))])
+	fileName = strings.TrimSuffix(fileName, filepath.Ext(fileName))
+	fileName = strings.ToLower(fileName)
+	result, err := Merge(*kubeConfig, *toBeAppend, fileName, *overridePtr)
 	if err != nil {
 		log.Panic(err)
 	}
@@ -186,5 +240,5 @@ func main() {
 	if err != nil {
 		log.Panic(err)
 	}
-	fmt.Printf("%s was modified successfully\n", kubeConfigPath)
+	log.Printf("%s was modified successfully\n", kubeConfigPath)
 }