implements data-url fetching

components/net/data_loader.rs

@@ -4,12 +4,14 @@
 
 use hyper::mime::{Mime, TopLevel, SubLevel, Attr, Value};
 use mime_classifier::MIMEClassifier;
-use net_traits::ProgressMsg::{Done, Payload};
-use net_traits::{LoadConsumer, LoadData, Metadata};
+use net_traits::LoadConsumer;
+use net_traits::ProgressMsg::{Payload, Done};
+use net_traits::{LoadData, Metadata};
 use resource_thread::{CancellationListener, send_error, start_sending_sniffed_opt};
 use rustc_serialize::base64::FromBase64;
 use std::sync::Arc;
 use url::SchemeData;
+use url::Url;
 use url::percent_encoding::percent_decode;
 
 pub fn factory(load_data: LoadData,
@@ -23,17 +25,19 @@ pub fn factory(load_data: LoadData,
     load(load_data, senders, classifier, cancel_listener)
 }
 
-pub fn load(load_data: LoadData,
-            start_chan: LoadConsumer,
-            classifier: Arc<MIMEClassifier>,
-            cancel_listener: CancellationListener) {
-    let url = load_data.url;
-    assert!(&*url.scheme == "data");
+pub enum DecodeError {
+    InvalidDataUri,
+    NonBase64DataUri,
+}
 
+pub type DecodeData = (Mime, Vec<u8>);
+
+pub fn decode(url: &Url) -> Result<DecodeData, DecodeError> {
+    assert!(&*url.scheme == "data");
     // Split out content type and data.
     let mut scheme_data = match url.scheme_data {
         SchemeData::NonRelative(ref scheme_data) => scheme_data.clone(),
-        _ => panic!("Expected a non-relative scheme URL.")
+        _ => panic!("Expected a non-relative scheme URL."),
     };
     match url.query {
         Some(ref query) => {
@@ -44,8 +48,7 @@ pub fn load(load_data: LoadData,
     }
     let parts: Vec<&str> = scheme_data.splitn(2, ',').collect();
     if parts.len() != 2 {
-        send_error(url, "invalid data uri".to_owned(), start_chan);
-        return;
+        return Err(DecodeError::InvalidDataUri);
     }
 
     // ";base64" must come at the end of the content type, per RFC 2397.
@@ -69,31 +72,45 @@ pub fn load(load_data: LoadData,
                                  vec!((Attr::Charset, Value::Ext("US-ASCII".to_owned())))));
     }
 
-    if cancel_listener.is_cancelled() {
-        return;
-    }
-
     let bytes = percent_decode(parts[1].as_bytes());
     let bytes = if is_base64 {
         // FIXME(#2909): It’s unclear what to do with non-alphabet characters,
         // but Acid 3 apparently depends on spaces being ignored.
         let bytes = bytes.into_iter().filter(|&b| b != ' ' as u8).collect::<Vec<u8>>();
         match bytes.from_base64() {
-            Err(..) => return send_error(url, "non-base64 data uri".to_owned(), start_chan),
+            Err(..) => return Err(DecodeError::NonBase64DataUri),
             Ok(data) => data,
         }
     } else {
         bytes
     };
+    Ok((content_type.unwrap(), bytes))
+}
 
-    let mut metadata = Metadata::default(url);
-    metadata.set_content_type(content_type.as_ref());
-    if let Ok(chan) = start_sending_sniffed_opt(start_chan,
+pub fn load(load_data: LoadData,
+            start_chan: LoadConsumer,
+            classifier: Arc<MIMEClassifier>,
+            cancel_listener: CancellationListener) {
+    let url = load_data.url;
+
+    if cancel_listener.is_cancelled() {
+        return;
+    }
+
+    match decode(&url) {
+        Ok((content_type, bytes)) => {
+            let mut metadata = Metadata::default(url);
+            metadata.set_content_type(Some(content_type).as_ref());
+            if let Ok(chan) = start_sending_sniffed_opt(start_chan,
                                                 metadata,
                                                 classifier,
                                                 &bytes,
                                                 load_data.context) {
-        let _ = chan.send(Payload(bytes));
-        let _ = chan.send(Done(Ok(())));
+                let _ = chan.send(Payload(bytes));
+                let _ = chan.send(Done(Ok(())));
+            }
+        },
+        Err(DecodeError::InvalidDataUri) => send_error(url, "invalid data uri".to_owned(), start_chan),
+        Err(DecodeError::NonBase64DataUri) => send_error(url, "non-base64 data uri".to_owned(), start_chan),
     }
 }

components/net/fetch/methods.rs

@@ -2,6 +2,7 @@
  * 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 data_loader::decode;
 use fetch::cors_cache::{BasicCORSCache, CORSCache, CacheRequestDetails};
 use http_loader::{NetworkHttpRequestFactory, create_http_connector, obtain_response};
 use hyper::header::{Accept, CacheControl, IfMatch, IfRange, IfUnmodifiedSince, Location};
@@ -305,7 +306,23 @@ fn basic_fetch(request: Rc<Request>) -> Response {
             http_fetch(request.clone(), BasicCORSCache::new(), false, false, false)
         },
 
-        "blob" | "data" | "file" | "ftp" => {
+        "data" => {
+            if *request.method.borrow() == Method::Get {
+                match decode(&url) {
+                    Ok((mime, bytes)) => {
+                        let mut response = Response::new();
+                        *response.body.lock().unwrap() = ResponseBody::Done(bytes);
+                        response.headers.set(ContentType(mime));
+                        response
+                    },
+                    Err(_) => Response::network_error()
+                }
+            } else {
+                Response::network_error()
+            }
+        },
+
+        "blob" | "file" | "ftp" => {
             // XXXManishearth handle these
             panic!("Unimplemented scheme for Fetch")
         },