banner.txt ansi color code not working in Windows 10 console

Hello. banner.txt ansi colors doesn’t work in Windows 10 console. Example:

banner.txt ${AnsiColor.RED}HELLO

The “HELLO” word should be red colored, but it doesn’t in both cmd console and powershell console. But Window10 still supports ansi colors:

https://msdn.microsoft.com/en-us/library/windows/desktop/mt638032(v=vs.85).aspx

To test it I wrote a simple .bat file able to show colors in a standard cmd console:

test.bat @echo <ESC>[31mHELLO<ESC>[0m

Where <ESC> is the escape character (alt+027). This .bat shows the “HELLO” word red colored.

I tried to use the same escape sequence in banner.txt but it doesn’t work too. It displays a broken character followed by [31m

Perhaps Spring Boot ansi constants are incorrect for a Window 10 environment?

[wzgy]

Windows 10 turns the Virtual Terminal Support OFF by default. You have three options: 1.In registry key [HKEY_CURRENT_USER\Console], create or set the VirtualTerminalLevel DWORD value to 1 2.Call to the SetConsoleMode() Windows API inside your program 3.Pipe output from external programs to Out-Host, like java -jar xxx.jar | Out-Host

https://stackoverflow.com/a/51681675/9480909

[maurocap]

I did a small research: it looks like pure java is not able to output ansi color the way a Windows console want them. I’ve found this project:

https://github.com/fusesource/jansi

Which expose two functions to enable/disable colored ansi output even on Windows. By using the library I was able to see colored output in a dos console:

public static void main(String[] args) {        
    AnsiConsole.systemInstall();
    System.out.println("\u001B[31mHELLO\u001B[37m");
    AnsiConsole.systemUninstall();
}

Anyway I was not able to see spring boot colored banner even with Jansi:

public static void main(String[] args) {
    AnsiConsole.systemInstall();
    SpringApplication.run(MyApplication.class, args);
    AnsiConsole.systemUninstall();
}

To summarize:

1. the missing banner colors in Windows console is not a Spring Boot issue
2. a Spring Boot very-low-priority feature could be to add Jansi or part of its functionalities to have colored consoles even in Windows environment

Thanks to everyone!