Move "oauth2" manifest key parsing out of Extension class.

chrome/common/extensions/api/identity/oauth2_manifest_handler.cc

+// Copyright (c) 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.
+
+#include "chrome/common/extensions/api/identity/oauth2_manifest_handler.h"
+
+#include "base/memory/scoped_ptr.h"
+#include "base/utf_string_conversions.h"
+#include "base/values.h"
+#include "chrome/common/extensions/extension_manifest_constants.h"
+#include "extensions/common/error_utils.h"
+
+namespace keys = extension_manifest_keys;
+namespace errors = extension_manifest_errors;
+
+namespace {
+
+// Manifest keys.
+const char kClientId[] = "client_id";
+const char kScopes[] = "scopes";
+
+}  // namespace
+
+namespace extensions {
+
+OAuth2Info::OAuth2Info() {}
+OAuth2Info::~OAuth2Info() {}
+
+// static
+const OAuth2Info& OAuth2Info::GetOAuth2Info(const Extension* extension) {

[Devlin, 2013/01/16 19:36:12]

I interpreted Yoyo's comment as "if it's never going to be NULL under normal
circumstances (i.e., access after key-parse), have it return a const & which is
guaranteed to exist (avoiding ever crashing)." This would mean returning an
empty const & ('empty' here being a default-constructed OAuth2Info) in the cases
where we haven't parsed it.

Yoyo, is this correct?

[SanjoyPal, 2013/01/16 20:11:28]

Do you mean, we should return a default-constructed OAuth2Info instead of a
CHECK() ?
// static
const OAuth2Info& OAuth2Info::GetOAuth2Info(const Extension* extension) {
  OAuth2Info* info = static_cast<OAuth2Info*>(
      extension->GetManifestData(keys::kOAuth2));
  return info ? *info : *scoped_ptr<OAuth2Info>(new OAuth2Info).get();
}


On 2013/01/16 19:36:12, D Cronin wrote:

[Devlin, 2013/01/16 20:26:39]

Yes and no. If we return a const &, it should always be valid, and if the
extension doesn't have one (because the key hasn't been parsed yet), then it
should return a default-constructed OAuth2Info. That part is correct. :)

But the code in your comment would break - it's returning a const & to an object
which is destructed at the end of the method call, the moment the scoped_ptr
goes out of scope.  And creating an object which will not be deleted at the end
of the function won't work, because it'll leak.  Instead, use a LazyInstance or
a Singleton to hold a single default-constructed OAuth2Info, and return the
reference to that when needed.

On 2013/01/16 20:11:28, SanjoyPal wrote:

[Yoyo Zhou, 2013/01/16 21:06:12]

Yes, that's what I meant. You should have an empty OAuth2Info lazy instance that
you return a reference to if the extension doesn't have any OAuth2-associated
data.

[SanjoyPal, 2013/01/16 23:03:13]

Done.

+  OAuth2Info* info = static_cast<OAuth2Info*>(
+      extension->GetManifestData(keys::kOAuth2));
+  CHECK(info);
+  return *info;
+}
+
+OAuth2ManifestHandler::OAuth2ManifestHandler() {
+}
+
+OAuth2ManifestHandler::~OAuth2ManifestHandler() {
+}
+
+bool OAuth2ManifestHandler::Parse(const base::Value* value,
+                                  Extension* extension, string16* error) {
+  scoped_ptr<OAuth2Info> info(new OAuth2Info);
+  const DictionaryValue* dict = NULL;
+  if (!value->GetAsDictionary(&dict) ||
+      !dict->GetString(kClientId, &info->client_id) ||
+      info->client_id.empty()) {
+    *error = ASCIIToUTF16(errors::kInvalidOAuth2ClientId);
+    return false;
+  }
+
+  const ListValue* list = NULL;
+  if (!dict->GetList(kScopes, &list)) {
+    *error = ASCIIToUTF16(errors::kInvalidOAuth2Scopes);
+    return false;
+  }
+
+  for (size_t i = 0; i < list->GetSize(); ++i) {
+    std::string scope;
+    if (!list->GetString(i, &scope)) {
+      *error = ASCIIToUTF16(errors::kInvalidOAuth2Scopes);
+      return false;
+    }
+    info->scopes.push_back(scope);
+  }
+
+  extension->SetManifestData(keys::kOAuth2, info.release());
+  return true;
+}
+
+bool OAuth2ManifestHandler::HasNoKey(Extension* extension, string16* error) {
+  extension->SetManifestData(keys::kOAuth2, new OAuth2Info);
+  return true;
+}
+
+}  // namespace extensions