You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: compress.rs
    path of file: ./repos/simple-http-server/src/middlewares
    
    the code of the file until where you have to start completion: use std::io;

use flate2::{
    write::{DeflateEncoder, GzEncoder},
    Compression,
};
use iron::headers::{ContentEncoding, ContentLength, Encoding, TransferEncoding};
use iron::response::WriteBody;
use iron::{AfterMiddleware, IronResult, Request, Response};

// [Reference]: https://github.com/iron/iron/issues/548
struct GzipBody(Box<dyn WriteBody>);
struct DeflateBody(Box<dyn WriteBody>);

impl WriteBody for GzipBody {
    fn write_body(&mut self, w: &mut dyn io::Write) -> io::Result<()> {
        let mut w = GzEncoder::new(w, Compression::default());
        self.0.write_body(&mut w)?;
        w.finish().map(|_| ())
    }
}

impl WriteBody for DeflateBody {
    fn write_body(&mut self, w: &mut dyn io::Write) -> io::Result<()> {
        let mut w = DeflateEncoder::
    
    fn after(&self, _: &mut Request, mut resp: Response) -> IronResult<Response> {
        if let Some(&ContentLength(length)) = resp.headers.get::<ContentLength>() {
            if length <= 256 {
                resp.headers.remove::<ContentEncoding>();
                return Ok(resp);
            }
        }

        let mut encoding: Option<Encoding> = None;
        if let Some(ContentEncoding(objs)) = resp.headers.get::<ContentEncoding>() {
            encoding = objs
                .iter()
                .find(|obj| *obj == &Encoding::Deflate || *obj == &Encoding::Gzip)
                .cloned();
        }
        if encoding.is_none() {
            if let Some(TransferEncoding(objs)) = resp.headers.get::<TransferEncoding>() {
                encoding = objs
                    .iter()
                    .find(|obj| *obj == &Encoding::Deflate || *obj == &Encoding::Gzip)
                    .cloned();
            }
        }

        if resp.body.is_some() {
            match encoding {
                Some(Encoding::Gzip) => {
                    // TransferEncoding will be `chunked`
                    resp.headers.remove::<ContentLength>();
                    resp.body = Some(Box::new(GzipBody(resp.body.take().unwrap())));
                }
                Some(Encoding::Deflate) => {
                    // TransferEncoding will be `chunked`
                    resp.headers.remove::<ContentLength>();
                    resp.body = Some(Box::new(DeflateBody(resp.body.take().unwrap())));
                }
                _ => {}
            }
        }
        Ok(resp)
    }