Initial code generation for features.

tools/json_schema_compiler/features_compiler.py

Index: tools/json_schema_compiler/features_compiler.py
diff --git a/tools/json_schema_compiler/features_compiler.py b/tools/json_schema_compiler/features_compiler.py
new file mode 100755
index 0000000000000000000000000000000000000000..2303dd7c5ff5c78414a947e4dee2e917f3d0e7aa
--- /dev/null
+++ b/tools/json_schema_compiler/features_compiler.py
@@ -0,0 +1,76 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+"""Generator for C++ features from json files.
+
+Usage example:
+  features_compiler.py --destdir gen --root /home/Work/src _permissions.json
+"""
+
+import optparse
+import os
+
+from schema_loader import SchemaLoader
+from features_cc_generator import CCGenerator
+from features_h_generator import HGenerator
+from model import CreateFeature
+
+
+def _GenerateSchema(filename, root, destdir, namespace):
+  """Generates C++ features files from the json file |filename|.
+  """
+  # Load in the feature permissions from the JSON file.
+  schema = os.path.normpath(filename)
+  schema_loader = SchemaLoader(os.path.dirname(os.path.relpath(schema, root)),
+    os.path.dirname(schema))
+  schema_filename = os.path.splitext(schema)[0]
+  feature_defs = schema_loader.LoadSchema(schema)
+
+  # Generate a list of the features defined and a list of their models.
+  feature_list = []
+  for feature_def, feature in feature_defs.iteritems():
+    feature_list.append(CreateFeature(feature_def, feature))
+
+  source_file_dir, _ = os.path.split(schema)
+  relpath = os.path.relpath(os.path.normpath(source_file_dir), root)
+  full_path = os.path.join(relpath, schema)
+
+  generators = [
+      ('%s.cc' % schema_filename, CCGenerator()),
+      ('%s.h' % schema_filename, HGenerator())
+  ]
+
+  # Generate and output the code for all features.
+  output_code = []
+  for filename, generator in generators:
+    code = generator.Generate(feature_list, full_path, namespace).Render()
+    if destdir:
+      with open(os.path.join(destdir, relpath, filename), 'w') as f:
+        f.write(code)
+    output_code += [filename, '', code, '']
+
+  return '\n'.join(output_code)
+
+
+if __name__ == '__main__':
+  parser = optparse.OptionParser(
+      description='Generates a C++ features model from JSON schema',
+      usage='usage: %prog [option]... schema')
+  parser.add_option('-r', '--root', default='.',
+      help='logical include root directory. Path to schema files from '
+           'specified dir will be the include path.')
+  parser.add_option('-d', '--destdir',
+      help='root directory to output generated files.')
+  parser.add_option('-n', '--namespace', default='generated_features',
+      help='C++ namespace for generated files. e.g extensions::api.')
+  (opts, filenames) = parser.parse_args()
+
+  # Only one file is currently specified.
+  if len(filenames) != 1:
+    raise ValueError('One (and only one) file is required (for now).')
+
+  result = _GenerateSchema(filenames[0], opts.root, opts.destdir,
+                           opts.namespace)
+  if not opts.destdir:
+    print result