Code generation for extensions api

tools/json_schema_compiler/compiler.py

Index: tools/json_schema_compiler/compiler.py
diff --git a/tools/json_schema_compiler/compiler.py b/tools/json_schema_compiler/compiler.py
new file mode 100644
index 0000000000000000000000000000000000000000..8315e9b0b92a08f18398fdf650c6523f96c55686
--- /dev/null
+++ b/tools/json_schema_compiler/compiler.py
@@ -0,0 +1,80 @@
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.

[not at google - send to devlin, 2012/01/17 05:42:32]

#!/usr/bin/env python

[calamity, 2012/01/18 05:43:08]

Done.

+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+

[not at google - send to devlin, 2012/01/17 05:42:32]

We should probably add a general of comment of what this tool is for and how to
use it beyond the 'usage' stuff. Mention its history as a tool for generating
extension API code.

See like tools/coverity/coverity.py for inspiration.

[calamity, 2012/01/18 05:43:08]

Done.

+import model
+import os.path
+import json
+import cc_generator
+import h_generator
+import optparse
+import sys
+
+parser = optparse.OptionParser(
+    description='Generate C++ boilerplate code for extension apis from json',

[not at google - send to devlin, 2012/01/17 05:42:32]

"Generates a C++ model of a JSON schema" or something.  Take out reference to
extension APIs.

[calamity, 2012/01/18 05:43:08]

Done.

+    usage='usage: %prog [options] target referenced_jsons')

[not at google - send to devlin, 2012/01/17 05:42:32]

I think a more unixy way of saying something like this is

usage='usage: %prog [option]... schema [referenced_schema]...'

[calamity, 2012/01/18 05:43:08]

Done.

+parser.add_option('-r', '--root', default='.',
+    help='logical include root directory. Path to json 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',
+    help='C++ namespace for generated files')
+parser.add_option('-s', '--suffix', default='_api',
+    help='C++ namespace suffix for generated files')
+
+(opts, args) = parser.parse_args()
+if not args:
+  sys.exit('Error: No input json file')

[not at google - send to devlin, 2012/01/17 05:42:32]

Print usage instead of just "Error.." ?

[calamity, 2012/01/18 05:43:08]

Done.

+dest_dir = opts.destdir
+root_namespace = opts.namespace
+filename_suffix = opts.suffix
+
+target_json = os.path.normpath(args[0])

[not at google - send to devlin, 2012/01/17 05:42:32]

it's not actually target, that implies output.  this is input, so should be
"source_schema" or just "schema" (that would match the "usage" line).

likewise for all use of "target*" in this file.

+referenced_jsons = args[1:]
+
+json_model = model.Model()
+
+# Load type dependencies into the model

[not at google - send to devlin, 2012/01/17 05:42:32]

fullstop

[calamity, 2012/01/18 05:43:08]

Done.

+for json_path in referenced_jsons:
+  json_path = os.path.normpath(json_path)
+  api_file = open(json_path, 'r')
+  api_defs = json.loads(api_file.read())
+  api_file.close()
+
+  for namespace in api_defs:
+    json_model.add_namespace(namespace, root_namespace,
+        os.path.relpath(json_path, opts.root), filename_suffix)
+
+# Actually generate for target file.
+target_api_file = open(target_json, 'r')
+target_api_defs = json.loads(target_api_file.read())
+target_api_file.close()
+for target_namespace in target_api_defs:
+  namespace = json_model.add_namespace(target_namespace, root_namespace,
+      # Gets the relative path from opts.root to the target_json to correctly
+      # determine the include path
+      os.path.relpath(target_json, opts.root), filename_suffix)

[not at google - send to devlin, 2012/01/17 05:42:32]

pull this comment and the os.path.relpath(...) thing into a local variable.
also "include path" is confusing to me, implies #include or something, it's just
a relative path to the source file right?

[calamity, 2012/01/18 05:43:08]

Include path is the #include path? The relative path from src is being used as
the #include path to the file.

[calamity, 2012/01/18 05:43:08]

Well, it's the output path here, but the #include path for the referenced
jsons...

[not at google - send to devlin, 2012/01/18 06:57:28]

Cool, this can be 1 line now?

Also, comment above needs a fullstop.

+  if not namespace:
+    continue
+  cc_generator = cc_generator.CCGenerator(namespace, json_model)
+  cc_code = cc_generator.generate().render()
+  h_generator = h_generator.HGenerator(namespace, json_model)
+  h_code = h_generator.generate().render()
+  if dest_dir:
+    cc_file = open(os.path.join(dest_dir, namespace.parent_dir,
+        namespace.filename + '.cc'), 'w')
+    cc_file.write(cc_code)
+    cc_file.close()
+    h_file = open(os.path.join(dest_dir, namespace.parent_dir,
+        namespace.filename + '.h'), 'w')
+    h_file.write(h_code)
+    h_file.close()
+  else:
+    print '%s.h' % namespace.filename
+    print
+    print h_code
+    print
+    print '%s.cc\n' % namespace.filename
+    print
+    print cc_code