Auto merge of #11536 - izgzhen:add-blob-loader, r=Manishearth

Add blob loader

Add a blob loader to implement [Blob URL](https://w3c.github.io/FileAPI/#url). The related interfaces to script thread are also declared.

Progressing in parallel with PR #11534. Related to #11131.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix part of #10539

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- [x] These changes do not require tests because not integrated yet.

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components/net/blob_loader.rs

@@ -0,0 +1,87 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+use filemanager_thread::BlobURLStore;
+use hyper::header::{DispositionType, ContentDisposition, DispositionParam};
+use hyper::header::{Headers, ContentType, ContentLength, Charset};
+use hyper::http::RawStatus;
+use mime::{Mime, Attr};
+use mime_classifier::MIMEClassifier;
+use net_traits::ProgressMsg::Done;
+use net_traits::blob_url_store::{parse_blob_url, BlobURLStoreEntry, BlobURLStoreError};
+use net_traits::response::HttpsState;
+use net_traits::{LoadConsumer, LoadData, Metadata, NetworkError};
+use resource_thread::{send_error, start_sending_sniffed_opt};
+use std::str;
+use std::sync::{Arc, RwLock};
+
+
+// TODO: Check on GET
+// https://w3c.github.io/FileAPI/#requestResponseModel
+
+pub fn load(load_data: LoadData, consumer: LoadConsumer,
+            blob_url_store: Arc<RwLock<BlobURLStore>>,
+            classifier: Arc<MIMEClassifier>) { // XXX: Move it into net process later
+
+    match parse_blob_url(&load_data.url) {
+        None => {
+            let format_err = NetworkError::Internal(format!("Invalid blob URL format {:?}", load_data.url));
+            send_error(load_data.url.clone(), format_err, consumer);
+        }
+        Some((uuid, _fragment)) => {
+            match blob_url_store.read().unwrap().request(uuid, &load_data.url.origin()) {
+                Ok(entry) => load_blob(&load_data, consumer, classifier, entry),
+                Err(e) => {
+                    let err = match e {
+                        BlobURLStoreError::InvalidKey =>
+                            format!("Invalid blob URL key {:?}", uuid.simple().to_string()),
+                        BlobURLStoreError::InvalidOrigin =>
+                            format!("Invalid blob URL origin {:?}", load_data.url.origin()),
+                    };
+                    send_error(load_data.url.clone(), NetworkError::Internal(err), consumer);
+                }
+            }
+        }
+    }
+}
+
+fn load_blob(load_data: &LoadData,
+             start_chan: LoadConsumer,
+             classifier: Arc<MIMEClassifier>,
+             entry: &BlobURLStoreEntry) {
+    let content_type: Mime = entry.type_string.parse().unwrap_or(mime!(Text / Plain));
+    let charset = content_type.get_param(Attr::Charset);
+
+    let mut headers = Headers::new();
+
+    if let Some(ref name) = entry.filename {
+        let charset = charset.and_then(|c| c.as_str().parse().ok());
+        headers.set(ContentDisposition {
+            disposition: DispositionType::Inline,
+            parameters: vec![
+                DispositionParam::Filename(charset.unwrap_or(Charset::Us_Ascii),
+                                           None, name.as_bytes().to_vec())
+            ]
+        });
+    }
+
+    headers.set(ContentType(content_type.clone()));
+    headers.set(ContentLength(entry.size));
+
+    let metadata = Metadata {
+        final_url: load_data.url.clone(),
+        content_type: Some(ContentType(content_type.clone())),
+        charset: charset.map(|c| c.as_str().to_string()),
+        headers: Some(headers),
+        // https://w3c.github.io/FileAPI/#TwoHundredOK
+        status: Some(RawStatus(200, "OK".into())),
+        https_state: HttpsState::None,
+    };
+
+    if let Ok(chan) =
+        start_sending_sniffed_opt(start_chan, metadata, classifier,
+                                  &entry.bytes, load_data.context.clone()) {
+        let _ = chan.send(Done(Ok(())));
+    }
+}

components/net/filemanager_thread.rs

@@ -2,20 +2,27 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use blob_loader;
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
+use mime_classifier::MIMEClassifier;
 use mime_guess::guess_mime_type_opt;
+use net_traits::blob_url_store::{BlobURLStoreEntry, BlobURLStoreError};
 use net_traits::filemanager_thread::{FileManagerThreadMsg, FileManagerResult};
 use net_traits::filemanager_thread::{SelectedFile, FileManagerThreadError};
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::Read;
 use std::path::{Path, PathBuf};
+use std::sync::{Arc, RwLock};
+use url::Origin;
 use util::thread::spawn_named;
 use uuid::Uuid;
 
 pub struct FileManager {
     receiver: IpcReceiver<FileManagerThreadMsg>,
     idmap: HashMap<Uuid, PathBuf>,
+    classifier: Arc<MIMEClassifier>,
+    blob_url_store: Arc<RwLock<BlobURLStore>>,
 }
 
 pub trait FileManagerThreadFactory {
@@ -41,6 +48,8 @@ impl FileManager {
         FileManager {
             receiver: recv,
             idmap: HashMap::new(),
+            classifier: Arc::new(MIMEClassifier::new()),
+            blob_url_store: Arc::new(RwLock::new(BlobURLStore::new())),
         }
     }
 
@@ -52,6 +61,11 @@ impl FileManager {
                 FileManagerThreadMsg::SelectFiles(sender) => self.select_files(sender),
                 FileManagerThreadMsg::ReadFile(sender, id) => self.read_file(sender, id),
                 FileManagerThreadMsg::DeleteFileID(id) => self.delete_fileid(id),
+                FileManagerThreadMsg::LoadBlob(load_data, consumer) => {
+                    blob_loader::load(load_data, consumer,
+                                      self.blob_url_store.clone(),
+                                      self.classifier.clone());
+                },
                 FileManagerThreadMsg::Exit => break,
             }
         }
@@ -156,3 +170,37 @@ impl FileManager {
         self.idmap.remove(&id);
     }
 }
+
+pub struct BlobURLStore {
+    entries: HashMap<Uuid, (Origin, BlobURLStoreEntry)>,
+}
+
+impl BlobURLStore {
+    pub fn new() -> BlobURLStore {
+        BlobURLStore {
+            entries: HashMap::new(),
+        }
+    }
+
+    pub fn request(&self, id: Uuid, origin: &Origin) -> Result<&BlobURLStoreEntry, BlobURLStoreError> {
+        match self.entries.get(&id) {
+            Some(ref pair) => {
+                if pair.0 == *origin {
+                    Ok(&pair.1)
+                } else {
+                    Err(BlobURLStoreError::InvalidOrigin)
+                }
+            }
+            None => Err(BlobURLStoreError::InvalidKey)
+        }
+    }
+
+    pub fn add_entry(&mut self, id: Uuid, origin: Origin, blob: BlobURLStoreEntry) {
+        self.entries.insert(id, (origin, blob));
+    }
+
+    pub fn delete_entry(&mut self, id: Uuid) {
+        self.entries.remove(&id);
+    }
+}
+

components/net/lib.rs

@@ -49,6 +49,7 @@ extern crate webrender_traits;
 extern crate websocket;
 
 pub mod about_loader;
+pub mod blob_loader;
 pub mod bluetooth_thread;
 pub mod chrome_loader;
 pub mod connector;

components/net_traits/blob_url_store.rs

@@ -0,0 +1,50 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+use ipc_channel::ipc::IpcSender;
+use std::str::FromStr;
+use url::Url;
+use uuid::Uuid;
+
+/// Errors returns to BlobURLStoreMsg::Request
+#[derive(Clone, Serialize, Deserialize)]
+pub enum BlobURLStoreError {
+    /// Invalid UUID key
+    InvalidKey,
+    /// Invalid URL origin
+    InvalidOrigin,
+}
+
+/// Blob URL store entry, a packaged form of Blob DOM object
+#[derive(Clone, Serialize, Deserialize)]
+pub struct BlobURLStoreEntry {
+    /// MIME type string
+    pub type_string: String,
+    /// Some filename if the backend of Blob is a file
+    pub filename: Option<String>,
+    /// Size of content in bytes
+    pub size: u64,
+    /// Content of blob
+    pub bytes: Vec<u8>,
+}
+
+/// Message-passing style interface between store and loader
+#[derive(Serialize, Deserialize)]
+pub enum BlobURLStoreMsg {
+    /// Request for an blob entry identified by uuid
+    Request(Uuid, IpcSender<Result<BlobURLStoreEntry, BlobURLStoreError>>),
+}
+
+/// Parse URL as Blob URL scheme's definition
+/// https://w3c.github.io/FileAPI/#DefinitionOfScheme
+pub fn parse_blob_url(url: &Url) -> Option<(Uuid, Option<&str>)> {
+    url.path_segments().and_then(|mut segments| {
+        let id_str = match (segments.next(), segments.next()) {
+            (Some(s), None) => s,
+            _ => return None,
+        };
+
+        Uuid::from_str(id_str).map(|id| (id, url.fragment())).ok()
+    })
+}

components/net_traits/filemanager_thread.rs

@@ -4,6 +4,7 @@
 
 use ipc_channel::ipc::IpcSender;
 use std::path::PathBuf;
+use super::{LoadConsumer, LoadData};
 use uuid::Uuid;
 
 #[derive(Debug, Deserialize, Serialize)]
@@ -29,6 +30,9 @@ pub enum FileManagerThreadMsg {
     /// Delete the FileID entry
     DeleteFileID(Uuid),
 
+    /// Load resource by Blob URL
+    LoadBlob(LoadData, LoadConsumer),
+
     /// Shut down this thread
     Exit,
 }

components/net_traits/lib.rs

@@ -43,6 +43,7 @@ use storage_thread::StorageThreadMsg;
 use url::Url;
 use websocket::header;
 
+pub mod blob_url_store;
 pub mod bluetooth_scanfilter;
 pub mod bluetooth_thread;
 pub mod filemanager_thread;