[Presentation API] Mojo typemap for content::PresentationConnectionMessage

content/common/presentation/presentation_struct_traits.cc

+// Copyright 2017 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 "content/common/presentation/presentation_struct_traits.h"
+
+#include "url/mojo/url_gurl_struct_traits.h"
+
+namespace mojo {
+
+bool StructTraits<blink::mojom::PresentationSessionInfoDataView,
+                  content::PresentationSessionInfo>::
+    Read(blink::mojom::PresentationSessionInfoDataView data,
+         content::PresentationSessionInfo* out) {
+  if (!data.ReadUrl(&(out->presentation_url)) ||
+      !data.ReadId(&(out->presentation_id))) {
+    return false;
+  }
+
+  if (out->presentation_id.empty() ||
+      !base::IsStringASCII(out->presentation_id) ||
+      out->presentation_id.length() >
+          content::PresentationSessionInfo::kMaxIdLength) {
+    return false;
+  }
+  return true;
+}
+
+bool StructTraits<blink::mojom::PresentationErrorDataView,
+                  content::PresentationError>::
+    Read(blink::mojom::PresentationErrorDataView data,
+         content::PresentationError* out) {
+  if (!data.ReadErrorType(&(out->error_type)) ||
+      !data.ReadMessage(&(out->message))) {
+    return false;
+  }
+
+  if (!base::IsStringUTF8(out->message) ||

[dcheng, 2017/02/28 06:45:27]

I think Mojo requires that strings are utf-8. +yzshen to confirm

[yzshen1, 2017/02/28 18:22:07]

We don't enforce it during validation at the moment. At the blink side, we
convert to WTF::String using fromUTF8() which will be null if the string is not
valid UTF8.

You and I chatted about whether to enforce it a while ago. But I haven't got
around to measure the performance impact. :/

+      out->message.length() > content::PresentationError::kMaxMessageLength) {
+    return false;
+  }
+
+  return true;
+}
+
+bool UnionTraits<blink::mojom::PresentationConnectionMessageDataView,
+                 content::PresentationConnectionMessage>::
+    Read(blink::mojom::PresentationConnectionMessageDataView data,
+         content::PresentationConnectionMessage* out) {
+  if (data.is_message()) {
+    //    out->message = std::string();

[dcheng, 2017/02/28 06:45:27]

Nit: remove commented out code here and below

[mark a. foltz, 2017/02/28 18:35:21]

Done.

+    if (!data.ReadMessage(&(out->message)) ||
+        out->message->length() >
+            content::kMaxPresentationConnectionMessageSize) {
+      return false;
+    }
+  } else {
+    //      out->data = std::vector<uint8_t>();
+    if (!data.ReadData(&(out->data)) ||
+        out->data->size() > content::kMaxPresentationConnectionMessageSize) {
+      return false;
+    }
+  }
+  return true;
+}
+}