tools/json_schema_compiler/features_compiler.py

   1 #!/usr/bin/env python
   2 # Copyright 2013 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5 """Generator for C++ features from json files.
   6
   7 Usage example:
   8   features_compiler.py --destdir gen --root /home/Work/src _permissions.json
   9 """
  10
  11 import optparse
  12 import os
  13
  14 from schema_loader import SchemaLoader
  15 from features_cc_generator import CCGenerator
  16 from features_h_generator import HGenerator
  17 from model import CreateFeature
  18
  19
  20 def _GenerateSchema(filename, root, destdir, namespace):
  21   """Generates C++ features files from the json file |filename|.
  22   """
  23   # Load in the feature permissions from the JSON file.
  24   schema = os.path.normpath(filename)
  25   schema_loader = SchemaLoader(os.path.dirname(os.path.relpath(schema, root)),
  26     os.path.dirname(schema))
  27   schema_filename = os.path.splitext(schema)[0]
  28   feature_defs = schema_loader.LoadSchema(schema)
  29
  30   # Generate a list of the features defined and a list of their models.
  31   feature_list = []
  32   for feature_def, feature in feature_defs.iteritems():
  33     feature_list.append(CreateFeature(feature_def, feature))
  34
  35   source_file_dir, _ = os.path.split(schema)
  36   relpath = os.path.relpath(os.path.normpath(source_file_dir), root)
  37   full_path = os.path.join(relpath, schema)
  38
  39   generators = [
  40       ('%s.cc' % schema_filename, CCGenerator()),
  41       ('%s.h' % schema_filename, HGenerator())
  42   ]
  43
  44   # Generate and output the code for all features.
  45   output_code = []
  46   for filename, generator in generators:
  47     code = generator.Generate(feature_list, full_path, namespace).Render()
  48     if destdir:
  49       with open(os.path.join(destdir, relpath, filename), 'w') as f:
  50         f.write(code)
  51     output_code += [filename, '', code, '']
  52
  53   return '\n'.join(output_code)
  54
  55
  56 if __name__ == '__main__':
  57   parser = optparse.OptionParser(
  58       description='Generates a C++ features model from JSON schema',
  59       usage='usage: %prog [option]... schema')
  60   parser.add_option('-r', '--root', default='.',
  61       help='logical include root directory. Path to schema files from '
  62            'specified dir will be the include path.')
  63   parser.add_option('-d', '--destdir',
  64       help='root directory to output generated files.')
  65   parser.add_option('-n', '--namespace', default='generated_features',
  66       help='C++ namespace for generated files. e.g extensions::api.')
  67   (opts, filenames) = parser.parse_args()
  68
  69   # Only one file is currently specified.
  70   if len(filenames) != 1:
  71     raise ValueError('One (and only one) file is required (for now).')
  72
  73   result = _GenerateSchema(filenames[0], opts.root, opts.destdir,
  74                            opts.namespace)
  75   if not opts.destdir:
  76     print result