Add colored console output

[poelzi]

TODO:

• Rebase after merging logging: Add support for QT_MESSAGE_PATTERN env var #3204

Colorize log level, thread-name and category of console output.
Supports the NO_COLOR environment for disabling color output.

Errors, warnings are clearly visible. Controllers and debug output is also clearly distinguished.

[Holzhaus]

These ANSI escape codes are only supported on Unix. Let's find out that broke QT_MESSAGE_PATTERN support and just use that instead.

[Holzhaus]

These ANSI escape codes are only supported on Unix. Let's find out that broke QT_MESSAGE_PATTERN support and just use that instead.

Found the issue. Just apply this patch:

diff --git a/src/util/logging.cpp b/src/util/logging.cpp
index c967947789..047f9a4902 100644
--- a/src/util/logging.cpp
+++ b/src/util/logging.cpp
@@ -195,24 +195,9 @@ void handleMessage(
         }
     }

-    QByteArray ba;
-    ba.reserve(baSize);
-
-    ba.append(levelName);
-    ba.append(" [");
-    ba.append(threadName, threadName.size());
-    if (categoryName) {
-        ba.append("] ");
-        ba.append(categoryName, categoryName_len);
-        ba.append(": ");
-    } else {
-        ba.append("]: ");
-    }
-    ba.append(input8Bit, input8Bit.size());
-    ba.append('\n');
-
-    // Verify that the reserved size matches the actual size
-    DEBUG_ASSERT(ba.size() == baSize);
+    QString logMessage = qFormatLogMessage(type, context, input);
+    QByteArray ba = logMessage.toLocal8Bit();
+    ba.append("\n");

     if (isDebugAssert) {
         if (s_debugAssertBreak) {

Then you can set QT_MESSAGE_PATTERN however you want, e.g.:

export QT_MESSAGE_PATTERN="`echo -e "\033[32m%{time h:mm:ss.zzz}%{if-category}\033[32m %{category}:%{endif} %{if-debug}\033[34m%{function}%{endif}%{if-warning}\033[31m%{backtrace depth=3}%{endif}%{if-critical}\033[31m%{backtrace depth=3}%{endif}%{if-fatal}\033[31m%{backtrace depth=3}%{endif}\033[0m %{message}"`"

[poelzi]

newer consoles of windows 10, alternative consoles, macosx support ansi colors. only old windows cmd does not support it.

[Holzhaus]

newer consoles of windows 10, alternative consoles, macosx support ansi colors. only old windows cmd does not support it.

OK, but why choose a more complex and way less powerful solution than what I posted above?

[poelzi]

[uklotzde]

Let's first merge #3204 before introducing any custom extensions.

[Be-ing]

#3204 has been merged. What is that status of this now?

[poelzi]

@Be-ing I don't know. The problem wtih #3204 is, that it now pollutes the log file with ansi codes if I set there something that looks nice. I added it to my nix-shell environment because I know that I will not look at those files and only use the log file.

So, I'm somehow inclined to simply close this, otherwise we would need some ansi sequence remover before writing to the log file.

[poelzi]

We could use https://code.woboq.org/qt5/qt-creator/src/libs/utils/ansiescapecodehandler.cpp.html to create the logfile version

[poelzi]

This one is better: https://stackoverflow.com/questions/43743242/qregularexpression-to-strip-ansi-control-codes

[uklotzde]

I am against adding more code to a performance critical path. Instead you could color your log file afterwards by applying regular expressions. This is nothing that needs to be added to production code where it runs for all users if only a few developers are actually using such a feature.

Only exception: Hidden behind a feature flag that is disabled by default. But then we still have to maintain the addtional code.

[Holzhaus]

The proper way would be to format log file messages always with the standard format, and only use the custom pattern to the terminal output. I don't know if that is possible though.

[uklotzde]

The proper way would be to format log file messages always with the standard format, and only use the custom pattern to the terminal output. I don't know if that is possible though.

Exactly, it should be additive and optional, not subtractive and mandatory.

[poelzi]

I misread the code. the formatting is only used for the terminal

[poelzi]

This is a new minimal version of it. I'm using this format now since the pull request and came to like it really much.
Looks like this:

[poelzi]

Would be cool if the scripting engine could determine which js function triggered the debug() and would fill the variable, but otherwise I'm super happy with that.

[daschuer]

15:22:34.647 [Main] warning  QCheckBox(0x55fdbf655b00, name="LibraryBPMButton")  does not have a property named  "alignment"
              warning [Main] QCheckBox(0x55afcafb1fa0, name="LibraryBPMButton")  does not have a property named  "alignment"

This swaps type and thread name. This should not happen.
This also adds a time stamp which is not related to color.

Not sure about the default value --color=auto. Mixxx is no console application so it should not waste CPU time to beautify the console output. However it is now only if one starts Mixxx from a console and makes Warnings more visible.

Maybe a good trade off. What doe other think?

In the same scene we can add a bash-completion snippet. :-P

[poelzi]

@daschuer changed the layout to reassemble the normal layout

[daschuer]

For the future: Please do not rebase an active PR. Else we need to review the PR from the beginning instead of only the fix.

[daschuer]

LGTM, Thank you.

[daschuer]

@uklotzde What do you think now?

[Holzhaus]

I don't see anything in the diff about the log file. Generally this looks good, but the log file should always be written without colors. Is that the case? I'm short on time atm, I'll have a look asap.

[poelzi]

@Holzhaus the file log is always without colors. The default is no colors and only if the stdout is detected as a tty the console output is colorized.

[uklotzde]

Works well and is helpful for debugging. Thank you! LGTM

[Be-ing]

Thanks for working on this. Mixxx's console output is easier to read now.