Added support for HTTP Range header

src/api.rs

@@ -1,6 +1,6 @@
 use diesel::prelude::*;
 use iron::prelude::*;
-use iron::headers::{Authorization, Basic};
+use iron::headers::{Authorization, Basic, Range};
 use iron::{AroundMiddleware, Handler, status};
 use mount::Mount;
 use router::Router;
@@ -25,6 +25,7 @@ use errors::*;
 use index;
 use playlist;
 use user;
+use serve;
 use thumbnails::*;
 use utils::*;
 use vfs::VFSSource;
@@ -443,7 +444,8 @@ fn serve(request: &mut Request, db: &DB) -> IronResult<Response> {
 	}
 
 	if is_song(real_path.as_path()) {
-		return Ok(Response::with((status::Ok, real_path)));
+		let range_header = request.headers.get::<Range>();
+		return serve::deliver(&real_path, range_header);
 	}
 
 	if is_image(real_path.as_path()) {

src/errors.rs

@@ -45,6 +45,7 @@ error_chain! {
         IncorrectCredentials {}
         CannotServeDirectory {}
         UnsupportedFileType {}
+        FileNotFound {}
         MissingIndexVersion {}
     }
 }

src/main.rs

@@ -73,6 +73,7 @@ mod playlist;
 mod ui;
 mod user;
 mod utils;
+mod serve;
 mod thumbnails;
 mod vfs;
 
@@ -90,8 +91,8 @@ fn main() {
 	}
 }
 
- #[cfg(unix)]
-fn daemonize(options : &getopts::Matches) -> Result<()> {
+#[cfg(unix)]
+fn daemonize(options: &getopts::Matches) -> Result<()> {
 	if options.opt_present("f") {
 		return Ok(());
 	}
@@ -112,7 +113,7 @@ fn run() -> Result<()> {
 	options.optopt("p", "port", "set polaris to run on a custom port", "PORT");
 	options.optopt("d", "database", "set the path to index database", "FILE");
 	options.optopt("w", "web", "set the path to web client files", "DIRECTORY");
-	
+
 	#[cfg(unix)]
 	options.optflag("f",
 	                "foreground",

src/serve.rs

@@ -0,0 +1,169 @@
+use std::cmp;
+use std::fs::{self, File};
+use std::io::{self, Read, Seek, SeekFrom, Write};
+use std::path::Path;
+use iron::headers::{AcceptRanges, ByteRangeSpec, ContentLength, ContentRange, ContentRangeSpec,
+                    Range, RangeUnit};
+use iron::modifier::Modifier;
+use iron::modifiers::Header;
+use iron::prelude::*;
+use iron::response::WriteBody;
+use iron::status::{self, Status};
+
+use errors::{Error, ErrorKind};
+
+pub fn deliver(path: &Path, range_header: Option<&Range>) -> IronResult<Response> {
+
+	match fs::metadata(path) {
+		Ok(meta) => meta,
+		Err(e) => {
+			let status = match e.kind() {
+				io::ErrorKind::NotFound => status::NotFound,
+				io::ErrorKind::PermissionDenied => status::Forbidden,
+				_ => status::InternalServerError,
+			};
+			return Err(IronError::new(e, status));
+		}
+	};
+
+	let accept_range_header = Header(AcceptRanges(vec![RangeUnit::Bytes]));
+	let range_header = range_header.map(|h| h.clone());
+
+	match range_header {
+		None => Ok(Response::with((status::Ok, path, accept_range_header))),
+		Some(range) => {
+			match range {
+				Range::Bytes(vec_range) => {
+					if let Ok(partial_file) = PartialFile::from_path(path, vec_range) {
+						Ok(Response::with((status::Ok, partial_file, accept_range_header)))
+					} else {
+						Err(Error::from(ErrorKind::FileNotFound).into())
+					}
+				}
+				_ => Ok(Response::with(status::RangeNotSatisfiable)),
+			}
+		}
+	}
+}
+
+pub enum PartialFileRange {
+	AllFrom(u64),
+	FromTo(u64, u64),
+	Last(u64),
+}
+
+impl From<ByteRangeSpec> for PartialFileRange {
+	fn from(b: ByteRangeSpec) -> PartialFileRange {
+		match b {
+			ByteRangeSpec::AllFrom(from) => PartialFileRange::AllFrom(from),
+			ByteRangeSpec::FromTo(from, to) => PartialFileRange::FromTo(from, to),
+			ByteRangeSpec::Last(last) => PartialFileRange::Last(last),
+		}
+	}
+}
+
+pub struct PartialFile {
+	file: File,
+	range: PartialFileRange,
+}
+
+impl From<Vec<ByteRangeSpec>> for PartialFileRange {
+	fn from(v: Vec<ByteRangeSpec>) -> PartialFileRange {
+		match v.into_iter().next() {
+			None => PartialFileRange::AllFrom(0),
+			Some(byte_range) => PartialFileRange::from(byte_range),
+		}
+	}
+}
+
+impl PartialFile {
+	pub fn new<Range>(file: File, range: Range) -> PartialFile
+		where Range: Into<PartialFileRange>
+	{
+		let range = range.into();
+		PartialFile {
+			file: file,
+			range: range,
+		}
+	}
+
+	pub fn from_path<P: AsRef<Path>, Range>(path: P, range: Range) -> Result<PartialFile, io::Error>
+		where Range: Into<PartialFileRange>
+	{
+		let file = File::open(path.as_ref())?;
+		Ok(Self::new(file, range))
+	}
+}
+
+
+impl Modifier<Response> for PartialFile {
+	fn modify(self, res: &mut Response) {
+		use self::PartialFileRange::*;
+		let metadata: Option<_> = self.file.metadata().ok();
+		let file_length: Option<u64> = metadata.map(|m| m.len());
+		let range: Option<(u64, u64)> = match (self.range, file_length) {
+			(FromTo(from, to), Some(file_length)) => {
+				if from <= to && from < file_length {
+					Some((from, cmp::min(to, file_length - 1)))
+				} else {
+					None
+				}
+			}
+			(AllFrom(from), Some(file_length)) => {
+				if from < file_length {
+					Some((from, file_length - 1))
+				} else {
+					None
+				}
+			}
+			(Last(last), Some(file_length)) => {
+				if last < file_length {
+					Some((file_length - last, file_length - 1))
+				} else {
+					Some((0, file_length - 1))
+				}
+			}
+			(_, None) => None,
+
+		};
+		if let Some(range) = range {
+			let content_range = ContentRange(ContentRangeSpec::Bytes {
+			                                     range: Some(range),
+			                                     instance_length: file_length,
+			                                 });
+			let content_len = range.1 - range.0 + 1;
+			res.headers.set(ContentLength(content_len));
+			res.headers.set(content_range);
+			let partial_content = PartialContentBody {
+				file: self.file,
+				offset: range.0,
+				len: content_len,
+			};
+			res.status = Some(Status::PartialContent);
+			res.body = Some(Box::new(partial_content));
+		} else {
+			if let Some(file_length) = file_length {
+				res.headers
+					.set(ContentRange(ContentRangeSpec::Bytes {
+					                      range: None,
+					                      instance_length: Some(file_length),
+					                  }));
+			};
+			res.status = Some(Status::RangeNotSatisfiable);
+		}
+	}
+}
+
+struct PartialContentBody {
+	pub file: File,
+	pub offset: u64,
+	pub len: u64,
+}
+
+impl WriteBody for PartialContentBody {
+	fn write_body(&mut self, res: &mut Write) -> io::Result<()> {
+		self.file.seek(SeekFrom::Start(self.offset))?;
+		let mut limiter = <File as Read>::by_ref(&mut self.file).take(self.len);
+		io::copy(&mut limiter, res).map(|_| ())
+	}
+}