Code generation for extensions api

tools/json_schema_compiler/generate_h.py

+# Copyright (c) 2011 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.
+
+from model import PropertyType
+import code
+
+class H_Generator(object):
+  """A .h generator for a namespace."""
+
+  def __init__(self, namespace, model):
+    self.type_manager = code.TypeManager(namespace, model)
+    self.namespace = namespace
+
+  def generate(self):
+    """Generates the .h code for self.namespace.
+
+    Returns a code.Code object.
+    """
+    include_path = self.namespace.parent_dir
+    filename = self.namespace.filename
+    c = code.Code()
+    c.append(code.CHROMIUM_LICENSE).append()
+    c.append(code.WARNING_MESSAGE % self.namespace.parent_path)
+    c.append()
+
+    ifndef_name = generate_ifndef_name(include_path, filename)
+    c.append('#ifndef %s' % ifndef_name)
+    c.append('#define %s' % ifndef_name)
+    c.append('#pragma once')
+    c.append()
+    c.append('#include <string>')
+    c.append('#include <vector>')
+    c.append()
+    c.append('#include "base/basictypes.h"')
+    c.append('#include "base/memory/scoped_ptr.h"')
+    c.append('#include "base/values.h"')
+    c.append()
+    c.append('using base::Value;')
+    c.append('using base::DictionaryValue;')
+    c.append('using base::ListValue;')
+    c.append()
+
+    includes = self.type_manager.resolve_generated_includes()
+    if includes.code:
+      c.add(includes)
+      c.append()
+
+    c.append('namespace extensions {')
+    c.append('namespace %s {' % filename)
+    c.append()
+    c.append('//')
+    c.append('// Types')
+    c.append('//')
+    c.append()
+    for tipe in self.namespace.types.values():
+      c.add(self.generate_type(tipe))
+      c.append()
+    c.append('//')
+    c.append('// Functions')
+    c.append('//')
+    c.append()
+    for function in self.namespace.functions.values():
+      c.add(self.generate_function(function))
+      c.append()
+    c.append()
+    c.append()
+    c.append('} // namespace extensions')
+    c.append('} // namespace %s' % filename)
+    c.append()
+    c.append('#endif // %s' % ifndef_name)
+    return c
+
+  def generate_type(self, tipe, serializable=True):
+    """Generates a struct for a type."""
+    classname = code.cpp_name(tipe.name)
+    c = code.Code()
+    if tipe.description:
+      c.comment(tipe.description)
+    c.sblock('struct %(classname)s {')
+    c.append('~%(classname)s();')
+    c.append('%(classname)s();')
+    c.append()
+    for prop in tipe.properties.values():
+      if prop.description:
+        c.comment(prop.description)
+      if prop.optional:
+        c.append('scoped_ptr<%s> %s;' % (
+            self.type_manager.get_generic_type(prop), prop.name))
+      else:
+        c.append('%s %s;' % (self.type_manager.get_type(prop), prop.name))
+      c.append()
+
+    c.append('// Populates a %(classname)s object from a Value. Returns')
+    c.append('// whether |out| was successfully populated.')
+    c.append('static bool Populate(const Value& value, %(classname)s* out);')
+    c.append()
+    if serializable:
+      c.append('// Returns a new Value representing the serialized form')
+      c.append('// of this %(classname)s object.')
+      c.append('Value* ToValue() const;')
+    c.eblock()
+    c.sblock(' private:')
+    c.append('DISALLOW_COPY_AND_ASSIGN(%(classname)s);')
+
+    c.eblock('};')
+    c.substitute({'classname': classname})
+    return c
+
+  def generate_function(self, function):
+    """Generates the structs for a function."""
+    c = code.Code()
+    c.sblock('struct %s {' % code.cpp_name(function.name))
+    c.add(self.generate_function_params(function))
+    c.add(self.generate_function_result(function))
+    c.eblock('};')
+    return c
+
+  def generate_function_params(self, function):
+    """Generates the struct for passing parameters into a function."""
+    c = code.Code()
+
+    c.sblock('struct Params {')
+    for param in function.params:
+      if param.description:
+        c.comment(param.description)
+      if param.type == PropertyType.OBJECT:
+        c.add(self.generate_type(param, serializable=False))
+        c.append()
+    for param in function.params:
+      c.append('%s %s;' % (self.type_manager.get_type(param), param.name))
+
+    if function.params:
+      c.append()
+      c.append('Params();')
+      c.append('~Params();')
+
+      c.append()
+      c.append('static bool Populate(const ListValue& args, Params* out);')
+      c.eblock()
+      c.sblock(' private:')
+      c.append('DISALLOW_COPY_AND_ASSIGN(Params);')
+
+    c.eblock('};')
+    c.append()
+
+    return c
+
+  def generate_function_result(self, function):
+    """Generates the struct for passing a function's result back."""
+    # TODO(calamity): Handle returning an object
+    c = code.Code()
+
+    # TODO(calamity): Put this comment in less stupid place
+    if function.callback.param.description:
+      c.comment(function.callback.param.description)
+    c.append('class Result {')
+    c.sblock(' public:')
+    arg = ''
+    # TODO(calamity): handle object
+    if function.callback.param:
+      arg = 'const ' + self.type_manager.parameter_declaration(
+          function.callback.param,
+          type_modifiers={PropertyType.REF: code.ParamFormat.REFERENCE})
+    c.append('static Value* Create(%s);' % arg)
+    c.eblock()
+    c.sblock(' private:')
+    c.append('Result() {};')
+    c.append('DISALLOW_COPY_AND_ASSIGN(Result);')
+    c.eblock('};')
+    c.append()
+
+    return c
+
+def generate_ifndef_name(path, filename):
+  """Formats a path and filename as a #define name.
+
+  e.g chrome/extensions/gen, file.h becomes CHROME_EXTENSIONS_GEN_FILE_H__.
+  """
+  return ('%s/%s_H__' % (path, filename)).upper().replace('/', '_')
+