diff --git a/flacinfo.py b/flacinfo.py index 3298a60..71f737d 100755 --- a/flacinfo.py +++ b/flacinfo.py @@ -27,14 +27,20 @@ VORBIS_ARG_NAME = { class NoSuchTag(Exception): + """Raised when trying to reverse the `VORBIS_ARG_NAME` dict on an invalid tag name""" + def __init__(self, tag): + super().__init__() self.tag = tag - super(NoSuchTag, self).__init__() def __str__(self): return "No such Vorbis tag {}".format(self.tag) +class MetaflacError(Exception): + """ Raised when an invocation of metaflac failed. """ + + def argparser(): """ Parses the arguments from sys.argv """ parser = argparse.ArgumentParser( @@ -63,12 +69,14 @@ def is_flac_file(path): """ Checks whether `path` refers to an existing, writeable flac file """ if not os.path.isfile(path) or not os.access(path, os.W_OK): return False - flac_run = subprocess.run( - ["metaflac", "--list", path], - stdout=subprocess.DEVNULL, - stderr=subprocess.DEVNULL, - ) - if flac_run.returncode != 0: + try: + subprocess.run( + ["metaflac", "--list", path], + stdout=subprocess.DEVNULL, + stderr=subprocess.DEVNULL, + check=True, + ) + except subprocess.CalledProcessError: return False # Metaflac failed to list the files' metadata return True @@ -94,18 +102,14 @@ def edit_flac(args): metaflac_args = make_metaflac_args(args) metaflac_args += args["file"] metaflac_args.insert(0, "metaflac") - metaflac_run = subprocess.run(metaflac_args) - - if metaflac_run.returncode != 0: - print( - ( - "\n\nMetaflac exited with return code {}. There was an error " - "during the execution, you should look at the output to " - "investigate it." - ).format(metaflac_run.returncode), - file=sys.stderr, - ) - sys.exit(metaflac_run.returncode) + try: + subprocess.run(metaflac_args, check=True) + except subprocess.CalledProcessError as exn: + raise MetaflacError( + "Failed to edit tags: metaflac exited with error {}. Output:\n{}".format( + exn.returncode, exn.stderr + ) + ) from exn def reverse_tag(vorbis_tag): @@ -123,7 +127,15 @@ def get_tags(path): metaflac_args += ["--show-tag", VORBIS_ARG_NAME[tag]] metaflac_args.append(path) - metaflac_run = subprocess.run(metaflac_args, stdout=subprocess.PIPE) + try: + metaflac_run = subprocess.run(metaflac_args, check=True, stdout=subprocess.PIPE) + except subprocess.CalledProcessError as exn: + raise MetaflacError( + ( + "Failed to get tags for {}: metaflac exited with error {}." + "Output:\n{}" + ).format(path, exn.returncode, exn.stderr) + ) from exn meta_out = metaflac_run.stdout.decode("utf-8") output = {} @@ -142,13 +154,14 @@ def show_tags(path): tags = get_tags(path) print("File: {}".format(path)) - max_len = max([len(tag) for tag in tags]) + tag_len = max([len(tag) for tag in tags]) + 1 for tag in tags: - print(" {}: {}{}".format(tag, " " * (max_len - len(tag)), tags[tag])) + print((" {:<" + str(tag_len) + "} {}").format(tag + ":", tags[tag])) print("") def main(): + """ Entrypoint function """ args = vars(argparser()) has_errors = False