[TANGO_RES_2_JSON] Refactoring

scripts/tango_res_2_json

@@ -6,14 +6,6 @@ import argparse
 import json
 from contextlib import closing
 
-parser = argparse.ArgumentParser(description='Tango DB res -> JSON converter.')
-parser.add_argument('res_in', nargs='?', default='-',
-                    help='input Tango DB res. file name or "-" for stdin')
-parser.add_argument('json_out', nargs='?', default='-',
-                    help='output JSON file name or "-" for stdout')
-
-args = parser.parse_args()
-
 def load_tango_res(f):
     executable = 'lima_launcher'
     klass = 'LimaLauncher'
@@ -66,22 +58,36 @@ def load_tango_res(f):
     return dict(executable=executable, server=server, klass=klass,
                 device=device, config=config)
 
-def json_indent(x, levels=1, indent=4):
+def json_indent_body(x, levels=1, indent=4):
     raw_lines = x.split('\n')
     lines = [' ' * (levels * indent) + l for l in raw_lines[1:-1]]
-    return '\n'.join(raw_lines[:1] + lines + raw_lines[-1:])
+    return raw_lines[:1] + lines + raw_lines[-1:]
+
+def main():
+    parser = argparse.ArgumentParser(description=('Tango DB res -> '
+                                                  'JSON converter.'))
+    parser.add_argument('res_in', nargs='?', default='-',
+                        help='input Tango DB res. file name or "-" for stdin')
+    parser.add_argument('json_out', nargs='?', default='-',
+                        help='output JSON file name or "-" for stdout')
 
-out_file = sys.stdout if args.json_out == '-' else open(args.json_out, 'wt')
-with closing(out_file):
-    in_file = sys.stdin if args.res_in == '-' else open(args.res_in, 'rt')
-    with closing(in_file):
-        data = load_tango_res(in_file)
-        json_data = dict([(k, v if k == 'config' else f'"{v}"')
-                          for k, v in data.items()])
+    args = parser.parse_args()
+
+    out_file = sys.stdout if args.json_out == '-' else open(args.json_out, 'wt')
+    with closing(out_file):
+        in_file = sys.stdin if args.res_in == '-' else open(args.res_in, 'rt')
+        with closing(in_file):
+            data = load_tango_res(in_file)
+        data = {k: v if k == 'config' else f'"{v}"' for k, v in data.items()}
         keys = ['executable', 'server', 'klass', 'device', 'config']
         good_key = lambda x: 'class' if x == 'klass' else x
         json_lines = ['{']
-        json_lines += [',\n'.join([f'"{good_key(k)}": {json_data[k]}'
+        json_lines += [',\n'.join([f'"{good_key(k)}": {data[k]}'
                                    for k in keys])]
         json_lines += ['}']
-    out_file.write(json_indent('\n'.join(json_lines)) + '\n')
+        lines = json_indent_body('\n'.join(json_lines))
+        out_file.write('\n'.join(lines + ['']))
+
+if __name__ == '__main__':
+    main()
+