re-structure blob, structured serialization

3 files changed, 156 insertions, 1 deletions

diff --git a/components/script_traits/Cargo.toml b/components/script_traits/Cargo.toml
index 87cb044d902..0635d99dda3 100644
--- a/components/script_traits/Cargo.toml
+++ b/components/script_traits/Cargo.toml
@@ -39,6 +39,7 @@ servo_url = {path = "../url"}
 style_traits = {path = "../style_traits", features = ["servo"]}
 time = "0.1.12"
 url = "2.0"
+uuid = {version = "0.8", features = ["v4"]}
 webdriver = "0.40"
 webgpu = {path = "../webgpu"}
 webrender_api = {git = "https://github.com/servo/webrender"}
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 13429a13251..440a412a979 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -17,9 +17,11 @@ extern crate malloc_size_of_derive;
 extern crate serde;
 
 mod script_msg;
+pub mod serializable;
 pub mod transferable;
 pub mod webdriver_msg;
 
+use crate::serializable::BlobImpl;
 use crate::transferable::MessagePortImpl;
 use crate::webdriver_msg::{LoadStatus, WebDriverScriptCommand};
 use bluetooth_traits::BluetoothRequest;
@@ -39,7 +41,9 @@ use libc::c_void;
 use log::warn;
 use media::WindowGLContext;
 use msg::constellation_msg::BackgroundHangMonitorRegister;
-use msg::constellation_msg::{BrowsingContextId, HistoryStateId, MessagePortId, PipelineId};
+use msg::constellation_msg::{
+    BlobId, BrowsingContextId, HistoryStateId, MessagePortId, PipelineId,
+};
 use msg::constellation_msg::{PipelineNamespaceId, TopLevelBrowsingContextId, TraversalDirection};
 use net_traits::image::base::Image;
 use net_traits::image_cache::ImageCache;
@@ -1039,6 +1043,8 @@ impl ScriptToConstellationChan {
 pub struct StructuredSerializedData {
     /// Data serialized by SpiderMonkey.
     pub serialized: Vec<u8>,
+    /// Serialized in a structured callback,
+    pub blobs: Option<HashMap<BlobId, BlobImpl>>,
     /// Transferred objects.
     pub ports: Option<HashMap<MessagePortId, MessagePortImpl>>,
 }
diff --git a/components/script_traits/serializable.rs b/components/script_traits/serializable.rs
new file mode 100644
index 00000000000..73840fb2c50
--- /dev/null
+++ b/components/script_traits/serializable.rs
@@ -0,0 +1,148 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! This module contains implementations in script that are serializable,
+//! as per https://html.spec.whatwg.org/multipage/#serializable-objects.
+//! The implementations are here instead of in script
+//! so that the other modules involved in the serialization don't have
+//! to depend on script.
+
+use msg::constellation_msg::BlobId;
+use net_traits::filemanager_thread::RelativePos;
+use std::cell::RefCell;
+use std::path::PathBuf;
+use uuid::Uuid;
+
+/// File-based blob
+#[derive(Debug, Deserialize, MallocSizeOf, Serialize)]
+pub struct FileBlob {
+    #[ignore_malloc_size_of = "Uuid are hard(not really)"]
+    id: Uuid,
+    #[ignore_malloc_size_of = "PathBuf are hard"]
+    name: Option<PathBuf>,
+    cache: RefCell<Option<Vec<u8>>>,
+    size: u64,
+}
+
+impl FileBlob {
+    /// Create a new file blob.
+    pub fn new(id: Uuid, name: Option<PathBuf>, cache: Option<Vec<u8>>, size: u64) -> FileBlob {
+        FileBlob {
+            id,
+            name,
+            cache: RefCell::new(cache),
+            size,
+        }
+    }
+
+    /// Get the size of the file.
+    pub fn get_size(&self) -> u64 {
+        self.size.clone()
+    }
+
+    /// Get the cached file data, if any.
+    pub fn get_cache(&self) -> Option<Vec<u8>> {
+        self.cache.borrow().clone()
+    }
+
+    /// Cache data.
+    pub fn cache_bytes(&self, bytes: Vec<u8>) {
+        *self.cache.borrow_mut() = Some(bytes);
+    }
+
+    /// Get the file id.
+    pub fn get_id(&self) -> Uuid {
+        self.id.clone()
+    }
+}
+
+/// The data backing a DOM Blob.
+#[derive(Debug, Deserialize, MallocSizeOf, Serialize)]
+pub struct BlobImpl {
+    /// UUID of the blob.
+    blob_id: BlobId,
+    /// Content-type string
+    type_string: String,
+    /// Blob data-type.
+    blob_data: BlobData,
+    /// Sliced blobs referring to this one.
+    slices: Vec<BlobId>,
+}
+
+/// Different backends of Blob
+#[derive(Debug, Deserialize, MallocSizeOf, Serialize)]
+pub enum BlobData {
+    /// File-based blob, whose content lives in the net process
+    File(FileBlob),
+    /// Memory-based blob, whose content lives in the script process
+    Memory(Vec<u8>),
+    /// Sliced blob, including parent blob-id and
+    /// relative positions of current slicing range,
+    /// IMPORTANT: The depth of tree is only two, i.e. the parent Blob must be
+    /// either File-based or Memory-based
+    Sliced(BlobId, RelativePos),
+}
+
+impl BlobImpl {
+    /// Construct memory-backed BlobImpl
+    pub fn new_from_bytes(bytes: Vec<u8>, type_string: String) -> BlobImpl {
+        let blob_id = BlobId::new();
+        let blob_data = BlobData::Memory(bytes);
+        BlobImpl {
+            blob_id,
+            type_string,
+            blob_data,
+            slices: vec![],
+        }
+    }
+
+    /// Construct file-backed BlobImpl from File ID
+    pub fn new_from_file(file_id: Uuid, name: PathBuf, size: u64, type_string: String) -> BlobImpl {
+        let blob_id = BlobId::new();
+        let blob_data = BlobData::File(FileBlob {
+            id: file_id,
+            name: Some(name),
+            cache: RefCell::new(None),
+            size: size,
+        });
+        BlobImpl {
+            blob_id,
+            type_string,
+            blob_data,
+            slices: vec![],
+        }
+    }
+
+    /// Construct a BlobImpl from a slice of a parent.
+    pub fn new_sliced(rel_pos: RelativePos, parent: BlobId, type_string: String) -> BlobImpl {
+        let blob_id = BlobId::new();
+        let blob_data = BlobData::Sliced(parent, rel_pos);
+        BlobImpl {
+            blob_id,
+            type_string,
+            blob_data,
+            slices: vec![],
+        }
+    }
+
+    /// Get a clone of the blob-id
+    pub fn blob_id(&self) -> BlobId {
+        self.blob_id.clone()
+    }
+
+    /// Get a clone of the type-string
+    pub fn type_string(&self) -> String {
+        self.type_string.clone()
+    }
+
+    /// Get a mutable ref to the data
+    pub fn blob_data(&self) -> &BlobData {
+        &self.blob_data
+    }
+
+    /// Get a mutable ref to the data
+    pub fn blob_data_mut(&mut self) -> &mut BlobData {
+        &mut self.blob_data
+    }
+}