ANSI processing workaround for Windows command prompt

[God-damnit-all]

For some reason, this little line of code in Python enables virtual terminal processing for Windows command prompt, allowing it to display ANSI color.

Details can be found in this comment on Stack Overflow: https://stackoverflow.com/questions/287871/how-do-i-print-colored-text-to-the-terminal/293633#comment124648740_54955094

[mikf]

I've also found this:

import ctypes

kernel32 = ctypes.windll.kernel32
kernel32.SetConsoleMode(kernel32.GetStdHandle(-11), 7)

I would prefer using the Windows API if possible. Could you test if this actually works? I only have access to Win7 at the moment and neither method does anything there.

I'd also like to put this functionality behind an option, especially if it were to call os.system("") on each program start:

diff --git a/gallery_dl/__init__.py b/gallery_dl/__init__.py
index d66e285c..104df063 100644
--- a/gallery_dl/__init__.py
+++ b/gallery_dl/__init__.py
@@ -154,6 +154,12 @@ def main():
                 else:
                     signal.signal(signal_num, signal.SIG_IGN)
 
+        # ANSI on Windows
+        if util.WINDOWS and config.get(("output",), "ansi"):
+            import ctypes
+            kernel32 = ctypes.windll.kernel32
+            kernel32.SetConsoleMode(kernel32.GetStdHandle(-11), 7)
+
         # extractor modules
         modules = config.get(("extractor",), "modules")
         if modules is not None:

[rautamiekka]

I only have access to Win7 at the moment

If you can run an x86-32 or x64 VM and get the installer ISO some way (M$ has an official tool to download an official Win10 ISO, and Win10 doesn't have a nearly as restricted trial period as before cuz it never runs out nor limits in such ways), that would work.

[God-damnit-all]

I've also found this:

import ctypes

kernel32 = ctypes.windll.kernel32
kernel32.SetConsoleMode(kernel32.GetStdHandle(-11), 7)

I would prefer using the Windows API if possible. Could you test if this actually works? I only have access to Win7 at the moment and neither method does anything there.

I'd also like to put this functionality behind an option, especially if it were to call os.system("") on each program start:

diff --git a/gallery_dl/__init__.py b/gallery_dl/__init__.py
index d66e285c..104df063 100644
--- a/gallery_dl/__init__.py
+++ b/gallery_dl/__init__.py
@@ -154,6 +154,12 @@ def main():
                 else:
                     signal.signal(signal_num, signal.SIG_IGN)
 
+        # ANSI on Windows
+        if util.WINDOWS and config.get(("output",), "ansi"):
+            import ctypes
+            kernel32 = ctypes.windll.kernel32
+            kernel32.SetConsoleMode(kernel32.GetStdHandle(-11), 7)
+
         # extractor modules
         modules = config.get(("extractor",), "modules")
         if modules is not None:

I'll give it a try, but people reported mix success with it so I went with the one everyone seemed to be recommending.

My first instinct was to put it behind an option like you suggested, but it seemed like the code for checking the options came after code that began writing to the console, and I was concerned that could have a negative effect.

[God-damnit-all]

Good news, the code seems to work. Though, instead of having an ansi option, it might be better to determine if ANSI is even going to be used to begin with. That would probably have to include checking the output settings defined by #2529 to see if they contain any ANSI escape codes.

Now that you know the code works, this PR is probably unnecessary since you likely have a more elegant implementation in mind than I can provide.