net/protocols/
file.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::fs::File;
6use std::future::{Future, ready};
7use std::io::{BufReader, Seek, SeekFrom};
8use std::pin::Pin;
9
10use headers::{ContentLength, ContentRange, ContentType, HeaderMapExt, Range};
11use http::Method;
12use net_traits::request::Request;
13use net_traits::response::{Response, ResponseBody};
14use net_traits::{NetworkError, ResourceFetchTiming};
15use tokio::sync::mpsc::unbounded_channel;
16
17use crate::fetch::methods::{DoneChannel, FetchContext};
18use crate::filemanager_thread::FILE_CHUNK_SIZE;
19use crate::local_directory_listing;
20use crate::protocols::{
21    ProtocolHandler, get_range_request_bounds, partial_content, range_not_satisfiable_error,
22};
23
24#[derive(Default)]
25pub struct FileProtocolHander {}
26
27impl ProtocolHandler for FileProtocolHander {
28    fn load<'a>(
29        &'a self,
30        request: &'a mut Request,
31        done_chan: &mut DoneChannel,
32        context: &FetchContext,
33    ) -> Pin<Box<dyn Future<Output = Response> + Send + 'a>> {
34        let url = request.current_url();
35
36        if request.method != Method::GET {
37            return Box::pin(ready(Response::network_error(NetworkError::InvalidMethod)));
38        }
39        let response = if let Ok(file_path) = url.to_file_path() {
40            if file_path.is_dir() {
41                return Box::pin(async move {
42                    local_directory_listing::fetch(request, url, file_path).await
43                });
44            }
45
46            if let Ok(file) = File::open(file_path.clone()) {
47                // Get range bounds (if any) and try to seek to the requested offset.
48                // If seeking fails, bail out with a NetworkError.
49                let file_size = match file.metadata() {
50                    Ok(metadata) => Some(metadata.len()),
51                    Err(_) => None,
52                };
53
54                let mut response =
55                    Response::new(url, ResourceFetchTiming::new(request.timing_type()));
56
57                let range_header = request.headers.typed_get::<Range>();
58                let is_range_request = range_header.is_some();
59                let Ok(range) = get_range_request_bounds(range_header, file_size.unwrap_or(0))
60                    .get_final(file_size)
61                else {
62                    range_not_satisfiable_error(&mut response);
63                    return Box::pin(ready(response));
64                };
65                let mut reader = BufReader::with_capacity(FILE_CHUNK_SIZE, file);
66                if reader.seek(SeekFrom::Start(range.start as u64)).is_err() {
67                    return Box::pin(ready(Response::network_error(NetworkError::InvalidMethod)));
68                }
69
70                // Set response status to 206 if Range header is present.
71                // At this point we should have already validated the header.
72                if is_range_request {
73                    partial_content(&mut response);
74                }
75
76                // Set Content-Length and Content-Range headers when end is determinable.
77                let end_byte = range.end.map(|e| e as u64).or(file_size);
78                if let Some(end_byte) = end_byte {
79                    let start_byte = range.start as u64;
80
81                    response
82                        .headers
83                        .typed_insert(ContentLength(end_byte - start_byte));
84                    if is_range_request &&
85                        let Ok(content_range) =
86                            ContentRange::bytes(start_byte..end_byte, file_size)
87                    {
88                        response.headers.typed_insert(content_range);
89                    }
90                }
91
92                // Set Content-Type header.
93                let mime = mime_guess::from_path(file_path).first_or_octet_stream();
94                response.headers.typed_insert(ContentType::from(mime));
95
96                // Setup channel to receive cross-thread messages about the file fetch
97                // operation.
98                let (mut done_sender, done_receiver) = unbounded_channel();
99                *done_chan = Some((done_sender.clone(), done_receiver));
100
101                *response.body.lock() = ResponseBody::Receiving(vec![]);
102
103                context.filemanager.fetch_file_in_chunks(
104                    &mut done_sender,
105                    reader,
106                    response.body.clone(),
107                    context.cancellation_listener.clone(),
108                    range,
109                );
110
111                response
112            } else {
113                Response::network_error(NetworkError::ResourceLoadError(
114                    "Opening file failed".into(),
115                ))
116            }
117        } else {
118            Response::network_error(NetworkError::ResourceLoadError(
119                "Constructing file path failed".into(),
120            ))
121        };
122
123        Box::pin(ready(response))
124    }
125}
net/protocols/file.rs

net/protocols/
file.rs
