DocBook: add script to start LilyPond on the generated file.

Not yet used anywhere in the code for now (see next commit).

lib/scripts/docbook_copy.py

@@ -0,0 +1,63 @@
+# -*- coding: utf-8 -*-
+
+# file docbook_copy.py
+# This file is part of LyX, the document processor.
+# Licence details can be found in the file COPYING.
+#
+# \author Thibaut Cuvelier
+#
+# Full author contact details are available in file CREDITS
+
+# Usage:
+#   python docbook_copy.py lilypond_book_command in.docbook out.docbook
+# This script copies the original DocBook file (directly produced by LyX) to the output DocBook file,
+# potentially applying a post-processing step. For now, the only implemented post-processing step is
+# LilyPond.
+# /!\ The original file may be modified by this script!
+
+
+import os
+import shutil
+import sys
+
+
+def need_lilypond(file):
+    # Really tailored to the kind of output lilypond.module makes (in lib/layouts).
+    with open(file, 'r') as f:
+        return "language='lilypond'" in f.read()
+
+
+def copy_docbook(args):
+    if len(args) != 4:
+        print('Exactly four arguments are expected, only %s found: %s.' % (len(args), args))
+        sys.exit(1)
+
+    # Parse the command line.
+    lilypond_command = args[1]
+    in_file = args[2]
+    out_file = args[3]
+
+    has_lilypond = lilypond_command != ""
+
+    # Apply LilyPond to the original file if available and needed.
+    if has_lilypond and need_lilypond(in_file):
+        # LilyPond requires that its input file has the .lyxml extension.
+        # Move the file, so that LilyPond doesn't have to erase the contents of the original file before
+        # writing the converted output.
+        in_lily_file = in_file.replace(".xml", ".lyxml")
+        shutil.move(in_file, in_lily_file)
+
+        # Start LilyPond on the copied file.
+        command = lilypond_command + ' --format=docbook ' + in_lily_file
+        if os.system(command) != 0:
+            print('Error from LilyPond')
+            sys.exit(1)
+
+        # Now, in_file should have the LilyPond-processed contents.
+
+    # Perform the final copy.
+    shutil.copyfile(in_file, out_file, follow_symlinks=False)
+
+
+if __name__ == '__main__':
+    copy_docbook(sys.argv)