Merge pull request #108 from patacrep/convert

Added a command line tool to convert between file formats

patacrep/songs/chordpro/__init__.py

@@ -1,8 +1,9 @@
 """Chordpro parser"""
 
 from jinja2 import Environment, FileSystemLoader, contextfunction
-import pkg_resources
+import jinja2
 import os
+import pkg_resources
 
 from patacrep import encoding, files
 from patacrep.songs import Song
@@ -63,11 +64,14 @@ class ChordproSong(Song):
         jinjaenv.filters['search_image'] = self.search_image
         jinjaenv.filters['search_partition'] = self.search_partition
 
-        return Renderer(
-            template=template,
-            encoding='utf8',
-            jinjaenv=jinjaenv,
-            ).template.render(context)
+        try:
+            return Renderer(
+                template=template,
+                encoding='utf8',
+                jinjaenv=jinjaenv,
+                ).template.render(context)
+        except jinja2.exceptions.TemplateNotFound:
+            raise NotImplementedError("Cannot convert to format '{}'.".format(output_format))
 
     @staticmethod
     @contextfunction

patacrep/songs/convert/__main__.py

@@ -0,0 +1,78 @@
+"""Conversion between formats
+
+See the :meth:`__usage` method for more information.
+"""
+
+import os
+import logging
+import sys
+
+from patacrep.build import DEFAULT_CONFIG
+from patacrep import files
+
+LOGGER = logging.getLogger(__name__)
+
+def __usage():
+    return "python3 -m patacrep.songs.convert INPUTFORMAT OUTPUTFORMAT FILES"
+
+def yesno(prompt):
+    while True:
+        answer = input("{} [yn](append * to remember) ".format(prompt)).strip().lower()
+        remember = (answer[-1] == "*")
+        if remember:
+            answer = answer[0:-1]
+        if answer == "y":
+            return True, remember
+        if answer == "n":
+            return False, remember
+
+def confirm(destname):
+    return yesno("File '{}' already exist. Overwrite?".format(destname))
+
+if __name__ == "__main__":
+    if len(sys.argv) < 4:
+        LOGGER.error("Invalid number of arguments.")
+        LOGGER.error("Usage: %s", __usage())
+        sys.exit(1)
+
+    source = sys.argv[1]
+    dest = sys.argv[2]
+    song_files = sys.argv[3:]
+
+    song_parsers = files.load_plugins(
+        datadirs=DEFAULT_CONFIG.get('datadir', []),
+        root_modules=['songs'],
+        keyword='SONG_PARSERS',
+        )
+
+    if source not in song_parsers:
+        LOGGER.error(
+            "Unknown file format '%s'. Available ones are %s.",
+            source,
+            ", ".join(["'{}'".format(key) for key in song_parsers.keys()])
+            )
+        sys.exit(1)
+
+    remember = False
+    for file in song_files:
+        song = song_parsers[source]("", file, DEFAULT_CONFIG)
+        try:
+            destname = "{}.{}".format(".".join(file.split(".")[:-1]), dest)
+            dest_exists = os.path.exists(destname)
+            if dest_exists and not remember:
+                overwrite, remember = confirm(destname)
+            if dest_exists and not overwrite:
+                continue
+            converted = song.render(dest)
+            with open(destname, "w") as destfile:
+                destfile.write(converted)
+
+        except NotImplementedError:
+            LOGGER.error("Cannot convert to format '%s'.", dest)
+            sys.exit(1)
+        except KeyboardInterrupt:
+            print()
+            LOGGER.info("Aborted by user.")
+            sys.exit(0)
+
+    sys.exit(0)