Add methods to CompiledFileSystem that memoize returned

file system interfaces for processing API schemas and
Parse()ing JSON configuration data.

This should reduce cron time by preventing configuration
files from being parsed multiple times.

BUG=295812, 305280
NOTRY=true

Review URL: https://codereview.chromium.org/32513005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230160 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 118 insertions, 0 deletions

diff --git a/chrome/common/extensions/docs/server2/schema_util.py b/chrome/common/extensions/docs/server2/schema_util.py
new file mode 100644
index 0000000..60c9f31
--- /dev/null
+++ b/chrome/common/extensions/docs/server2/schema_util.py
@@ -0,0 +1,118 @@
+# Copyright 2013 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 collections import defaultdict, Mapping
+
+from third_party.json_schema_compiler import json_parse, idl_schema, idl_parser
+
+
+def RemoveNoDocs(item):
+  '''Removes nodes that should not be rendered from an API schema.
+  '''
+  if json_parse.IsDict(item):
+    if item.get('nodoc', False):
+      return True
+    for key, value in item.items():
+      if RemoveNoDocs(value):
+        del item[key]
+  elif type(item) == list:
+    to_remove = []
+    for i in item:
+      if RemoveNoDocs(i):
+        to_remove.append(i)
+    for i in to_remove:
+      item.remove(i)
+  return False
+
+
+def DetectInlineableTypes(schema):
+  '''Look for documents that are only referenced once and mark them as inline.
+  Actual inlining is done by _InlineDocs.
+  '''
+  if not schema.get('types'):
+    return
+
+  ignore = frozenset(('value', 'choices'))
+  refcounts = defaultdict(int)
+  # Use an explicit stack instead of recursion.
+  stack = [schema]
+
+  while stack:
+    node = stack.pop()
+    if isinstance(node, list):
+      stack.extend(node)
+    elif isinstance(node, Mapping):
+      if '$ref' in node:
+        refcounts[node['$ref']] += 1
+      stack.extend(v for k, v in node.iteritems() if k not in ignore)
+
+  for type_ in schema['types']:
+    if not 'noinline_doc' in type_:
+      if refcounts[type_['id']] == 1:
+        type_['inline_doc'] = True
+
+
+def InlineDocs(schema):
+  '''Replace '$ref's that refer to inline_docs with the json for those docs.
+  '''
+  types = schema.get('types')
+  if types is None:
+    return
+
+  inline_docs = {}
+  types_without_inline_doc = []
+
+  # Gather the types with inline_doc.
+  for type_ in types:
+    if type_.get('inline_doc'):
+      inline_docs[type_['id']] = type_
+      for k in ('description', 'id', 'inline_doc'):
+        type_.pop(k, None)
+    else:
+      types_without_inline_doc.append(type_)
+  schema['types'] = types_without_inline_doc
+
+  def apply_inline(node):
+    if isinstance(node, list):
+      for i in node:
+        apply_inline(i)
+    elif isinstance(node, Mapping):
+      ref = node.get('$ref')
+      if ref and ref in inline_docs:
+        node.update(inline_docs[ref])
+        del node['$ref']
+      for k, v in node.iteritems():
+        apply_inline(v)
+
+  apply_inline(schema)
+
+
+def ProcessSchema(path, file_data):
+  '''Parses |file_data| using a method determined by checking the
+  extension of the file at the given |path|. Then, trims 'nodoc' and handles
+  inlineable types from the parsed schema data.
+  '''
+  def trim_and_inline(schema, is_idl=False):
+    '''Modifies an API schema in place by removing nodes that shouldn't be
+    documented and inlining schema types that are only referenced once.
+    '''
+    if RemoveNoDocs(schema):
+      # A return of True signifies that the entire schema should not be
+      # documented. Otherwise, only nodes that request 'nodoc' are removed.
+      return None
+    if is_idl:
+      DetectInlineableTypes(schema)
+    InlineDocs(schema)
+    return schema
+
+  if path.endswith('.idl'):
+    idl = idl_schema.IDLSchema(idl_parser.IDLParser().ParseData(file_data))
+    return trim_and_inline(idl.process()[0], is_idl=True)
+
+  schemas = json_parse.Parse(file_data)
+  for schema in schemas:
+    # Schemas could consist of one API schema (data for a specific API file)
+    # or multiple (data from extension_api.json).
+    trim_and_inline(schema)
+  return schemas