deprecation msgs for KUBECTX_CURRENT_{BG,FG}COLOR

Signed-off-by: Ahmet Alp Balkan <ahmetb@google.com>

cmd/kubectx/list.go

@@ -5,7 +5,6 @@ import (
 	"io"
 
 	"facette.io/natsort"
-	"github.com/fatih/color"
 	"github.com/pkg/errors"
 
 	"github.com/ahmetb/kubectx/internal/cmdutil"
@@ -30,17 +29,11 @@ func (_ ListOp) Run(stdout, stderr io.Writer) error {
 	ctxs := kc.ContextNames()
 	natsort.Sort(ctxs)
 
-	// TODO support KUBECTX_CURRENT_FGCOLOR
-	// TODO support KUBECTX_CURRENT_BGCOLOR
-
-	currentColor := color.New(color.FgGreen, color.Bold)
-	printer.EnableOrDisableColor(currentColor)
-
 	cur := kc.GetCurrentContext()
 	for _, c := range ctxs {
 		s := c
 		if c == cur {
-			s = currentColor.Sprint(c)
+			s = printer.ActiveItemColor.Sprint(c)
 		}
 		fmt.Fprintf(stdout, "%s\n", s)
 	}

cmd/kubectx/main.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"os"
 
+	"github.com/ahmetb/kubectx/internal/cmdutil"
 	"github.com/ahmetb/kubectx/internal/env"
 	"github.com/ahmetb/kubectx/internal/printer"
 )
@@ -14,6 +15,8 @@ type Op interface {
 }
 
 func main() {
+	cmdutil.PrintDeprecatedEnvWarnings(os.Stderr, os.Environ())
+
 	op := parseArgs(os.Args[1:])
 	if err := op.Run(os.Stdout, os.Stderr); err != nil {
 		printer.Error(os.Stderr, err.Error())

cmd/kubens/list.go

@@ -39,13 +39,11 @@ func (op ListOp) Run(stdout, stderr io.Writer) error {
 		return errors.Wrap(err, "could not list namespaces (is the cluster accessible?)")
 	}
 
-	currentColor := color.New(color.FgGreen, color.Bold)
-	printer.EnableOrDisableColor(currentColor)
 
 	for _, c := range ns {
 		s := c
 		if c == curNs {
-			s = currentColor.Sprint(c)
+			s = printer.ActiveItemColor.Sprint(c)
 		}
 		fmt.Fprintf(stdout, "%s\n", s)
 	}

cmd/kubens/main.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"os"
 
+	"github.com/ahmetb/kubectx/internal/cmdutil"
 	"github.com/ahmetb/kubectx/internal/env"
 	"github.com/ahmetb/kubectx/internal/printer"
 )
@@ -14,6 +15,7 @@ type Op interface {
 }
 
 func main() {
+	cmdutil.PrintDeprecatedEnvWarnings(os.Stderr, os.Environ())
 	op := parseArgs(os.Args[1:])
 	if err := op.Run(os.Stdout, os.Stderr); err != nil {
 		printer.Error(os.Stderr, err.Error())

internal/cmdutil/deprecated.go

@@ -0,0 +1,22 @@
+package cmdutil
+
+import (
+	"io"
+	"strings"
+
+	"github.com/ahmetb/kubectx/internal/printer"
+)
+
+func PrintDeprecatedEnvWarnings(out io.Writer, vars []string) {
+	for _, vv := range vars {
+		parts := strings.SplitN(vv, "=", 2)
+		if len(parts) != 2 {
+			continue
+		}
+		key := parts[0]
+
+		if key == `KUBECTX_CURRENT_FGCOLOR` || key == `KUBECTX_CURRENT_BGCOLOR` {
+				printer.Warning(out,"%s environment variable is now deprecated", key)
+		}
+	}
+}

internal/cmdutil/deprecated_test.go

@@ -0,0 +1,35 @@
+package cmdutil
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+func TestPrintDeprecatedEnvWarnings_noDeprecatedVars(t *testing.T){
+	var out bytes.Buffer
+	PrintDeprecatedEnvWarnings(&out, []string{
+		"A=B",
+		"PATH=/foo:/bar:/bin",
+	})
+	if v := out.String(); len(v) > 0{
+		t.Fatalf("something written to buf: %v", v)
+	}
+}
+
+
+func TestPrintDeprecatedEnvWarnings_bgColors(t *testing.T){
+	var out bytes.Buffer
+
+	PrintDeprecatedEnvWarnings(&out, []string{
+		"KUBECTX_CURRENT_FGCOLOR=1",
+		"KUBECTX_CURRENT_BGCOLOR=2",
+	})
+	v := out.String()
+	if !strings.Contains(v, "KUBECTX_CURRENT_FGCOLOR"){
+		t.Fatalf("output doesn't contain 'KUBECTX_CURRENT_FGCOLOR': %q", v)
+	}
+	if !strings.Contains(v, "KUBECTX_CURRENT_BGCOLOR"){
+		t.Fatalf("output doesn't contain 'KUBECTX_CURRENT_BGCOLOR': %q", v)
+	}
+}

internal/printer/color.go

@@ -8,6 +8,14 @@ import (
 	"github.com/ahmetb/kubectx/internal/env"
 )
 
+var (
+	ActiveItemColor = color.New(color.FgGreen, color.Bold)
+)
+
+func init(){
+	EnableOrDisableColor(ActiveItemColor)
+}
+
 // useColors returns true if colors are force-enabled,
 // false if colors are disabled, or nil for default behavior
 // which is determined based on factors like if stdout is tty.