funnel.rs

use redis::{Redis, Reply, ReplyBox, ReplyRef};
use std::io;

pub fn tape_addresses(redis: &mut Redis, tape_id: &str) -> io::Result<ServerSet> {
    let reply = try!(redis.command(&[
        b"EVAL",
        include_bytes!("funnel/tape_addresses.lua"),
        b"0",
        tape_id.as_bytes(),
    ]));
    Ok(ServerSet(reply))
}

pub struct ServerSet(ReplyBox);

impl ServerSet {
    pub fn iter<'a>(&'a self) -> ServerSetIter<'a> {
        match self.0.deref() {
            Reply::Array(servers) => ServerSetIter{servers: servers, offset: 0},
            _ => ServerSetIter{servers: &[], offset: 0},
        }
    }
}

// TODO: Delete this once #34511 is stable.
pub struct ServerSetIter<'a> {
    servers: &'a [ReplyRef],
    offset: usize,
}

impl<'a> Iterator for ServerSetIter<'a> {
    type Item = &'a [u8];

    fn next(&mut self) -> Option<&'a [u8]> {
        self.servers.get(self.offset)
            .and_then(|server| match server.deref() {
                Reply::String(name) => {
                    self.offset += 1;
                    Some(name)
                },
                _ => None,
            })
    }
}