Refactor config and split them in packages (#8351)

This change is related to larger config migration PR
change, this is a first stage change to move our
configs to `cmd/config/` - divided into its subsystems

pkg/color/color.go

@@ -0,0 +1,85 @@
+package color
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/fatih/color"
+	"github.com/mattn/go-isatty"
+)
+
+// global colors.
+var (
+	// Check if we stderr, stdout are dumb terminals, we do not apply
+	// ansi coloring on dumb terminals.
+	IsTerminal = func() bool {
+		return isatty.IsTerminal(os.Stdout.Fd()) && isatty.IsTerminal(os.Stderr.Fd())
+	}
+
+	Bold = func() func(a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.Bold).SprintFunc()
+		}
+		return fmt.Sprint
+	}()
+	Red = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgRed).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	Blue = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgBlue).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	Yellow = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgYellow).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	CyanBold = func() func(a ...interface{}) string {
+		if IsTerminal() {
+			color.New(color.FgCyan, color.Bold).SprintFunc()
+		}
+		return fmt.Sprint
+	}()
+	YellowBold = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgYellow, color.Bold).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	BgYellow = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.BgYellow).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	Black = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgBlack).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	FgRed = func() func(a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgRed).SprintFunc()
+		}
+		return fmt.Sprint
+	}()
+	BgRed = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.BgRed).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+	FgWhite = func() func(format string, a ...interface{}) string {
+		if IsTerminal() {
+			return color.New(color.FgWhite).SprintfFunc()
+		}
+		return fmt.Sprintf
+	}()
+)

pkg/env/env.go

@@ -0,0 +1,21 @@
+package env
+
+import "os"
+
+// Get retrieves the value of the environment variable named
+// by the key. If the variable is present in the environment the
+// value (which may be empty) is returned. Otherwise it returns
+// the specified default value.
+func Get(key, defaultValue string) string {
+	if v, ok := os.LookupEnv(key); ok {
+		return v
+	}
+	return defaultValue
+}
+
+// Lookup retrieves the value of the environment variable named
+// by the key. If the variable is present in the environment the
+// value (which may be empty) is returned and the boolean is true.
+// Otherwise the returned value will be empty and the boolean will
+// be false.
+func Lookup(key string) (string, bool) { return os.LookupEnv(key) }