Structural refactoring for multiple kubeconfig support (#219)

internal/cmdutil/util.go

@@ -0,0 +1,29 @@
+package cmdutil
+
+import (
+	"os"
+
+	"github.com/pkg/errors"
+)
+
+func HomeDir() string {
+	if v := os.Getenv("XDG_CACHE_HOME"); v != "" {
+		return v
+	}
+	home := os.Getenv("HOME")
+	if home == "" {
+		home = os.Getenv("USERPROFILE") // windows
+	}
+	return home
+}
+
+// IsNotFoundErr determines if the underlying error is os.IsNotExist. Right now
+// errors from github.com/pkg/errors doesn't work with os.IsNotExist.
+func IsNotFoundErr(err error) bool {
+	for e := err; e != nil; e = errors.Unwrap(e) {
+		if os.IsNotExist(e) {
+			return true
+		}
+	}
+	return false
+}

internal/cmdutil/util_test.go

@@ -0,0 +1,68 @@
+package cmdutil
+
+import (
+	"testing"
+
+	"github.com/ahmetb/kubectx/internal/testutil"
+)
+
+func Test_homeDir(t *testing.T) {
+	type env struct{ k, v string }
+	cases := []struct {
+		name string
+		envs []env
+		want string
+	}{
+		{
+			name: "XDG_CACHE_HOME precedence",
+			envs: []env{
+				{"XDG_CACHE_HOME", "xdg"},
+				{"HOME", "home"},
+			},
+			want: "xdg",
+		},
+		{
+			name: "HOME over USERPROFILE",
+			envs: []env{
+				{"HOME", "home"},
+				{"USERPROFILE", "up"},
+			},
+			want: "home",
+		},
+		{
+			name: "only USERPROFILE available",
+			envs: []env{
+				{"XDG_CACHE_HOME", ""},
+				{"HOME", ""},
+				{"USERPROFILE", "up"},
+			},
+			want: "up",
+		},
+		{
+			name: "none available",
+			envs: []env{
+				{"XDG_CACHE_HOME", ""},
+				{"HOME", ""},
+				{"USERPROFILE", ""},
+			},
+			want: "",
+		},
+	}
+
+	for _, c := range cases {
+		t.Run(c.name, func(tt *testing.T) {
+			var unsets []func()
+			for _, e := range c.envs {
+				unsets = append(unsets, testutil.WithEnvVar(e.k, e.v))
+			}
+
+			got := HomeDir()
+			if got != c.want {
+				t.Errorf("expected:%q got:%q", c.want, got)
+			}
+			for _, u := range unsets {
+				u()
+			}
+		})
+	}
+}

internal/kubeconfig/helper_test.go

@@ -11,12 +11,14 @@ type MockKubeconfigLoader struct {
 	out bytes.Buffer
 }
 
-func (t *MockKubeconfigLoader) Read(p []byte) (n int, err error)    { return t.in.Read(p) }
-func (t *MockKubeconfigLoader) Write(p []byte) (n int, err error)   { return t.out.Write(p) }
-func (t *MockKubeconfigLoader) Close() error                        { return nil }
-func (t *MockKubeconfigLoader) Reset() error                        { return nil }
-func (t *MockKubeconfigLoader) Load() (ReadWriteResetCloser, error) { return t, nil }
-func (t *MockKubeconfigLoader) Output() string                      { return t.out.String() }
+func (t *MockKubeconfigLoader) Read(p []byte) (n int, err error)  { return t.in.Read(p) }
+func (t *MockKubeconfigLoader) Write(p []byte) (n int, err error) { return t.out.Write(p) }
+func (t *MockKubeconfigLoader) Close() error                      { return nil }
+func (t *MockKubeconfigLoader) Reset() error                      { return nil }
+func (t *MockKubeconfigLoader) Load() ([]ReadWriteResetCloser, error) {
+	return []ReadWriteResetCloser{ReadWriteResetCloser(t)}, nil
+}
+func (t *MockKubeconfigLoader) Output() string { return t.out.String() }
 
 func WithMockKubeconfigLoader(kubecfg string) *MockKubeconfigLoader {
 	return &MockKubeconfigLoader{in: strings.NewReader(kubecfg)}

internal/kubeconfig/kubeconfig.go

@@ -15,7 +15,7 @@ type ReadWriteResetCloser interface {
 }
 
 type Loader interface {
-	Load() (ReadWriteResetCloser, error)
+	Load() ([]ReadWriteResetCloser, error)
 }
 
 type Kubeconfig struct {
@@ -38,11 +38,14 @@ func (k *Kubeconfig) Close() error {
 }
 
 func (k *Kubeconfig) Parse() error {
-	f, err := k.loader.Load()
+	files, err := k.loader.Load()
 	if err != nil {
 		return errors.Wrap(err, "failed to load")
 	}
 
+	// TODO since we don't support multiple kubeconfig files at the moment, there's just 1 file
+	f := files[0]
+
 	k.f = f
 	var v yaml.Node
 	if err := yaml.NewDecoder(f).Decode(&v); err != nil {

internal/kubeconfig/kubeconfigloader.go

@@ -1,27 +1,27 @@
-package cmdutil
+package kubeconfig
 
 import (
+	"github.com/ahmetb/kubectx/internal/cmdutil"
 	"os"
 	"path/filepath"
 
 	"github.com/pkg/errors"
-
-	"github.com/ahmetb/kubectx/internal/kubeconfig"
 )
 
 var (
-	DefaultLoader kubeconfig.Loader = new(StandardKubeconfigLoader)
+	DefaultLoader Loader = new(StandardKubeconfigLoader)
 )
 
 type StandardKubeconfigLoader struct{}
 
 type kubeconfigFile struct{ *os.File }
 
-func (*StandardKubeconfigLoader) Load() (kubeconfig.ReadWriteResetCloser, error) {
+func (*StandardKubeconfigLoader) Load() ([]ReadWriteResetCloser, error) {
 	cfgPath, err := kubeconfigPath()
 	if err != nil {
 		return nil, errors.Wrap(err, "cannot determine kubeconfig path")
 	}
+
 	f, err := os.OpenFile(cfgPath, os.O_RDWR, 0)
 	if err != nil {
 		if os.IsNotExist(err) {
@@ -29,7 +29,9 @@ func (*StandardKubeconfigLoader) Load() (kubeconfig.ReadWriteResetCloser, error)
 		}
 		return nil, errors.Wrap(err, "failed to open file")
 	}
-	return &kubeconfigFile{f}, nil
+
+	// TODO we'll return all kubeconfig files when we start implementing multiple kubeconfig support
+	return []ReadWriteResetCloser{ReadWriteResetCloser(&kubeconfigFile{f})}, nil
 }
 
 func (kf *kubeconfigFile) Reset() error {
@@ -52,31 +54,9 @@ func kubeconfigPath() (string, error) {
 	}
 
 	// default path
-	home := HomeDir()
+	home := cmdutil.HomeDir()
 	if home == "" {
 		return "", errors.New("HOME or USERPROFILE environment variable not set")
 	}
 	return filepath.Join(home, ".kube", "config"), nil
 }
-
-func HomeDir() string {
-	if v := os.Getenv("XDG_CACHE_HOME"); v != "" {
-		return v
-	}
-	home := os.Getenv("HOME")
-	if home == "" {
-		home = os.Getenv("USERPROFILE") // windows
-	}
-	return home
-}
-
-// IsNotFoundErr determines if the underlying error is os.IsNotExist. Right now
-// errors from github.com/pkg/errors doesn't work with os.IsNotExist.
-func IsNotFoundErr(err error) bool {
-	for e := err; e != nil; e = errors.Unwrap(e) {
-		if os.IsNotExist(e) {
-			return true
-		}
-	}
-	return false
-}

internal/kubeconfig/kubeconfigloader_test.go

@@ -1,76 +1,15 @@
-package cmdutil
+package kubeconfig
 
 import (
+	"github.com/ahmetb/kubectx/internal/cmdutil"
 	"os"
 	"path/filepath"
 	"strings"
 	"testing"
 
-	"github.com/ahmetb/kubectx/internal/kubeconfig"
 	"github.com/ahmetb/kubectx/internal/testutil"
 )
 
-func Test_homeDir(t *testing.T) {
-	type env struct{ k, v string }
-	cases := []struct {
-		name string
-		envs []env
-		want string
-	}{
-		{
-			name: "XDG_CACHE_HOME precedence",
-			envs: []env{
-				{"XDG_CACHE_HOME", "xdg"},
-				{"HOME", "home"},
-			},
-			want: "xdg",
-		},
-		{
-			name: "HOME over USERPROFILE",
-			envs: []env{
-				{"HOME", "home"},
-				{"USERPROFILE", "up"},
-			},
-			want: "home",
-		},
-		{
-			name: "only USERPROFILE available",
-			envs: []env{
-				{"XDG_CACHE_HOME", ""},
-				{"HOME", ""},
-				{"USERPROFILE", "up"},
-			},
-			want: "up",
-		},
-		{
-			name: "none available",
-			envs: []env{
-				{"XDG_CACHE_HOME", ""},
-				{"HOME", ""},
-				{"USERPROFILE", ""},
-			},
-			want: "",
-		},
-	}
-
-	for _, c := range cases {
-		t.Run(c.name, func(tt *testing.T) {
-			var unsets []func()
-			for _, e := range c.envs {
-				unsets = append(unsets, testutil.WithEnvVar(e.k, e.v))
-			}
-
-			got := HomeDir()
-			if got != c.want {
-				t.Errorf("expected:%q got:%q", c.want, got)
-			}
-			for _, u := range unsets {
-				u()
-			}
-		})
-	}
-}
-
 func Test_kubeconfigPath(t *testing.T) {
 	defer testutil.WithEnvVar("HOME", "/x/y/z")()
 
@@ -119,12 +58,12 @@ func Test_kubeconfigPath_envOvverideDoesNotSupportPathSeparator(t *testing.T) {
 
 func TestStandardKubeconfigLoader_returnsNotFoundErr(t *testing.T) {
 	defer testutil.WithEnvVar("KUBECONFIG", "foo")()
-	kc := new(kubeconfig.Kubeconfig).WithLoader(DefaultLoader)
+	kc := new(Kubeconfig).WithLoader(DefaultLoader)
 	err := kc.Parse()
 	if err == nil {
 		t.Fatal("expected err")
 	}
-	if !IsNotFoundErr(err) {
+	if !cmdutil.IsNotFoundErr(err) {
 		t.Fatalf("expected ENOENT error; got=%v", err)
 	}
 }