ssdp 0.7.0

An asynchronous abstraction for discovering devices and services on a network.
Documentation
use std::fmt::{Formatter, Display, Result};

use hyper::error::{self, Error};
use hyper::header::{HeaderFormat, Header};

use FieldMap;

const ST_HEADER_NAME: &'static str = "ST";

const ST_ALL_VALUE: &'static str = "ssdp:all";

/// Represents a header which specifies the search target.
#[derive(Clone, PartialEq, Eq, Hash, Debug)]
pub enum ST {
    All,
    Target(FieldMap),
}

impl Header for ST {
    fn header_name() -> &'static str {
        ST_HEADER_NAME
    }

    fn parse_header(raw: &[Vec<u8>]) -> error::Result<Self> {
        if raw.len() != 1 {
            return Err(Error::Header);
        }

        if &raw[0][..] == ST_ALL_VALUE.as_bytes() {
            Ok(ST::All)
        } else {
            FieldMap::parse_bytes(&raw[0][..]).map(ST::Target).ok_or(Error::Header)
        }
    }
}

impl HeaderFormat for ST {
    fn fmt_header(&self, fmt: &mut Formatter) -> Result {
        match *self {
            ST::All => try!(fmt.write_str(ST_ALL_VALUE)),
            ST::Target(ref n) => try!(Display::fmt(n, fmt)),
        };

        Ok(())
    }
}

#[cfg(test)]
mod tests {
    use hyper::header::Header;

    use FieldMap;
    use super::ST;

    #[test]
    fn positive_all() {
        let st_all_header = &[b"ssdp:all"[..].to_vec()];

        match ST::parse_header(st_all_header) {
            Ok(ST::All) => (),
            _ => panic!("Failed To Match ST::All Header"),
        }
    }

    #[test]
    fn positive_field_upnp() {
        let st_upnp_root_header = &[b"upnp:some_identifier"[..].to_vec()];

        match ST::parse_header(st_upnp_root_header) {
            Ok(ST::Target(FieldMap::UPnP(_))) => (),
            _ => panic!("Failed To Match ST::Target Header To FieldMap::UPnP"),
        }
    }

    #[test]
    fn positive_field_urn() {
        let st_urn_root_header = &[b"urn:some_identifier"[..].to_vec()];

        match ST::parse_header(st_urn_root_header) {
            Ok(ST::Target(FieldMap::URN(_))) => (),
            _ => panic!("Failed To Match ST::Target Header To FieldMap::URN"),
        }
    }

    #[test]
    fn positive_field_uuid() {
        let st_uuid_root_header = &[b"uuid:some_identifier"[..].to_vec()];

        match ST::parse_header(st_uuid_root_header) {
            Ok(ST::Target(FieldMap::UUID(_))) => (),
            _ => panic!("Failed To Match ST::Target Header To FieldMap::UUID"),
        }
    }

    #[test]
    #[should_panic]
    fn negative_multiple_headers() {
        let st_multiple_headers = &[b"uuid:some_identifier"[..].to_vec(), b"ssdp:all"[..].to_vec()];

        ST::parse_header(st_multiple_headers).unwrap();
    }
}