OP#792 initial commit after fork

cmd/update-notifier.go

@@ -0,0 +1,103 @@
+// Copyright (c) 2015-2021 MinIO, Inc.
+//
+// This file is part of MinIO Object Storage stack
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package cmd
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+	"time"
+
+	"github.com/cheggaaa/pb"
+	humanize "github.com/dustin/go-humanize"
+	"github.com/minio/minio/internal/color"
+)
+
+// prepareUpdateMessage - prepares the update message, only if a
+// newer version is available.
+func prepareUpdateMessage(downloadURL string, older time.Duration) string {
+	if downloadURL == "" || older <= 0 {
+		return ""
+	}
+
+	// Compute friendly duration string to indicate time
+	// difference between newer and current release.
+	t := time.Time{}
+	newerThan := humanize.RelTime(t, t.Add(older), "before the latest release", "")
+
+	if globalServerCtxt.JSON {
+		return fmt.Sprintf("You are running an older version of MinIO released %s, update: %s", newerThan, downloadURL)
+	}
+
+	// Return the nicely colored and formatted update message.
+	return colorizeUpdateMessage(downloadURL, newerThan)
+}
+
+// colorizeUpdateMessage - inspired from Yeoman project npm package https://github.com/yeoman/update-notifier
+func colorizeUpdateMessage(updateString string, newerThan string) string {
+	msgLine1Fmt := " You are running an older version of MinIO released %s "
+	msgLine2Fmt := " Update: %s "
+
+	// Calculate length *without* color coding: with ANSI terminal
+	// color characters, the result is incorrect.
+	line1Length := len(fmt.Sprintf(msgLine1Fmt, newerThan))
+	line2Length := len(fmt.Sprintf(msgLine2Fmt, updateString))
+
+	// Populate lines with color coding.
+	line1InColor := fmt.Sprintf(msgLine1Fmt, color.YellowBold(newerThan))
+	line2InColor := fmt.Sprintf(msgLine2Fmt, color.CyanBold(updateString))
+
+	// calculate the rectangular box size.
+	maxContentWidth := max(line1Length, line2Length)
+
+	// termWidth is set to a default one to use when we are
+	// not able to calculate terminal width via OS syscalls
+	termWidth := 25
+	if width, err := pb.GetTerminalWidth(); err == nil {
+		termWidth = width
+	}
+
+	// Box cannot be printed if terminal width is small than maxContentWidth
+	if maxContentWidth > termWidth {
+		return "\n" + line1InColor + "\n" + line2InColor + "\n\n"
+	}
+
+	topLeftChar := "┏"
+	topRightChar := "┓"
+	bottomLeftChar := "┗"
+	bottomRightChar := "┛"
+	horizBarChar := "━"
+	vertBarChar := "┃"
+	// on windows terminal turn off unicode characters.
+	if runtime.GOOS == globalWindowsOSName {
+		topLeftChar = "+"
+		topRightChar = "+"
+		bottomLeftChar = "+"
+		bottomRightChar = "+"
+		horizBarChar = "-"
+		vertBarChar = "|"
+	}
+
+	lines := []string{
+		color.YellowBold(topLeftChar + strings.Repeat(horizBarChar, maxContentWidth) + topRightChar),
+		color.YellowBold(vertBarChar) + line1InColor + strings.Repeat(" ", maxContentWidth-line1Length) + color.YellowBold(vertBarChar),
+		color.YellowBold(vertBarChar) + line2InColor + strings.Repeat(" ", maxContentWidth-line2Length) + color.YellowBold(vertBarChar),
+		color.YellowBold(bottomLeftChar + strings.Repeat(horizBarChar, maxContentWidth) + bottomRightChar),
+	}
+	return "\n" + strings.Join(lines, "\n") + "\n"
+}