refactor: remove cli::resources::Resource (#3285)

11 files changed, 219 insertions, 301 deletions

diff --git a/cli/lib.rs b/cli/lib.rs
index b6922c591..a22f61799 100644
--- a/cli/lib.rs
+++ b/cli/lib.rs
@@ -50,9 +50,7 @@ pub mod source_maps;
 mod startup_data;
 pub mod state;
 pub mod test_util;
-mod tokio_read;
 mod tokio_util;
-mod tokio_write;
 pub mod version;
 pub mod worker;
 
diff --git a/cli/ops/fetch.rs b/cli/ops/fetch.rs
index 1d330ce41..143331171 100644
--- a/cli/ops/fetch.rs
+++ b/cli/ops/fetch.rs
@@ -62,10 +62,10 @@ pub fn op_fetch(
     }
 
     let body = res.into_body();
-    let body_resource = resources::add_reqwest_body(body);
+    let rid = resources::add_reqwest_body(body);
 
     let json_res = json!({
-      "bodyRid": body_resource.rid,
+      "bodyRid": rid,
       "status": status.as_u16(),
       "statusText": status.canonical_reason().unwrap_or(""),
       "headers": res_headers
diff --git a/cli/ops/files.rs b/cli/ops/files.rs
index c1e43ff95..04b5f98bf 100644
--- a/cli/ops/files.rs
+++ b/cli/ops/files.rs
@@ -1,14 +1,19 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 use super::dispatch_json::{Deserialize, JsonOp, Value};
 use crate::deno_error::bad_resource;
+use crate::deno_error::DenoError;
+use crate::deno_error::ErrorKind;
 use crate::fs as deno_fs;
 use crate::ops::json_op;
 use crate::resources;
+use crate::resources::CliResource;
 use crate::state::ThreadSafeState;
 use deno::*;
 use futures::Future;
+use futures::Poll;
 use std;
 use std::convert::From;
+use std::io::SeekFrom;
 use tokio;
 
 pub fn init(i: &mut Isolate, s: &ThreadSafeState) {
@@ -86,8 +91,8 @@ fn op_open(
   let is_sync = args.promise_id.is_none();
   let op = open_options.open(filename).map_err(ErrBox::from).and_then(
     move |fs_file| {
-      let resource = resources::add_fs_file(fs_file);
-      futures::future::ok(json!(resource.rid))
+      let rid = resources::add_fs_file(fs_file);
+      futures::future::ok(json!(rid))
     },
   );
 
@@ -116,6 +121,31 @@ fn op_close(
   Ok(JsonOp::Sync(json!({})))
 }
 
+#[derive(Debug)]
+pub struct SeekFuture {
+  seek_from: SeekFrom,
+  rid: ResourceId,
+}
+
+impl Future for SeekFuture {
+  type Item = u64;
+  type Error = ErrBox;
+
+  fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+    let mut table = resources::lock_resource_table();
+    let resource = table
+      .get_mut::<CliResource>(self.rid)
+      .ok_or_else(bad_resource)?;
+
+    let tokio_file = match resource {
+      CliResource::FsFile(ref mut file) => file,
+      _ => return Err(bad_resource()),
+    };
+
+    tokio_file.poll_seek(self.seek_from).map_err(ErrBox::from)
+  }
+}
+
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
 struct SeekArgs {
@@ -131,10 +161,25 @@ fn op_seek(
   _zero_copy: Option<PinnedBuf>,
 ) -> Result<JsonOp, ErrBox> {
   let args: SeekArgs = serde_json::from_value(args)?;
+  let rid = args.rid as u32;
+  let offset = args.offset;
+  let whence = args.whence as u32;
+  // Translate seek mode to Rust repr.
+  let seek_from = match whence {
+    0 => SeekFrom::Start(offset as u64),
+    1 => SeekFrom::Current(i64::from(offset)),
+    2 => SeekFrom::End(i64::from(offset)),
+    _ => {
+      return Err(ErrBox::from(DenoError::new(
+        ErrorKind::InvalidSeekMode,
+        format!("Invalid seek mode: {}", whence),
+      )));
+    }
+  };
+
+  let fut = SeekFuture { seek_from, rid };
 
-  let resource = resources::lookup(args.rid as u32)?;
-  let op = resources::seek(resource, args.offset, args.whence as u32)
-    .and_then(move |_| futures::future::ok(json!({})));
+  let op = fut.and_then(move |_| futures::future::ok(json!({})));
   if args.promise_id.is_none() {
     let buf = op.wait()?;
     Ok(JsonOp::Sync(buf))
diff --git a/cli/ops/io.rs b/cli/ops/io.rs
index 98ac2f395..3ede4b411 100644
--- a/cli/ops/io.rs
+++ b/cli/ops/io.rs
@@ -1,18 +1,76 @@
 use super::dispatch_minimal::MinimalOp;
 use crate::deno_error;
+use crate::deno_error::bad_resource;
 use crate::ops::minimal_op;
 use crate::resources;
+use crate::resources::CliResource;
+use crate::resources::DenoAsyncRead;
+use crate::resources::DenoAsyncWrite;
 use crate::state::ThreadSafeState;
-use crate::tokio_read;
-use crate::tokio_write;
 use deno::*;
 use futures::Future;
+use futures::Poll;
 
 pub fn init(i: &mut Isolate, s: &ThreadSafeState) {
   i.register_op("read", s.core_op(minimal_op(op_read)));
   i.register_op("write", s.core_op(minimal_op(op_write)));
 }
 
+#[derive(Debug, PartialEq)]
+enum IoState {
+  Pending,
+  Done,
+}
+
+/// Tries to read some bytes directly into the given `buf` in asynchronous
+/// manner, returning a future type.
+///
+/// The returned future will resolve to both the I/O stream and the buffer
+/// as well as the number of bytes read once the read operation is completed.
+pub fn read<T>(rid: ResourceId, buf: T) -> Read<T>
+where
+  T: AsMut<[u8]>,
+{
+  Read {
+    rid,
+    buf,
+    state: IoState::Pending,
+  }
+}
+
+/// A future which can be used to easily read available number of bytes to fill
+/// a buffer.
+///
+/// Created by the [`read`] function.
+#[derive(Debug)]
+pub struct Read<T> {
+  rid: ResourceId,
+  buf: T,
+  state: IoState,
+}
+
+impl<T> Future for Read<T>
+where
+  T: AsMut<[u8]>,
+{
+  type Item = usize;
+  type Error = ErrBox;
+
+  fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+    if self.state == IoState::Done {
+      panic!("poll a Read after it's done");
+    }
+
+    let mut table = resources::lock_resource_table();
+    let resource = table
+      .get_mut::<CliResource>(self.rid)
+      .ok_or_else(bad_resource)?;
+    let nread = try_ready!(resource.poll_read(&mut self.buf.as_mut()[..]));
+    self.state = IoState::Done;
+    Ok(nread.into())
+  }
+}
+
 pub fn op_read(rid: i32, zero_copy: Option<PinnedBuf>) -> Box<MinimalOp> {
   debug!("read rid={}", rid);
   let zero_copy = match zero_copy {
@@ -22,13 +80,58 @@ pub fn op_read(rid: i32, zero_copy: Option<PinnedBuf>) -> Box<MinimalOp> {
     Some(buf) => buf,
   };
 
-  match resources::lookup(rid as u32) {
-    Err(e) => Box::new(futures::future::err(e)),
-    Ok(resource) => Box::new(
-      tokio_read::read(resource, zero_copy)
-        .map_err(ErrBox::from)
-        .and_then(move |(_resource, _buf, nread)| Ok(nread as i32)),
-    ),
+  let fut = read(rid as u32, zero_copy)
+    .map_err(ErrBox::from)
+    .and_then(move |nread| Ok(nread as i32));
+
+  Box::new(fut)
+}
+
+/// A future used to write some data to a stream.
+#[derive(Debug)]
+pub struct Write<T> {
+  rid: ResourceId,
+  buf: T,
+  state: IoState,
+}
+
+/// Creates a future that will write some of the buffer `buf` to
+/// the stream resource with `rid`.
+///
+/// Any error which happens during writing will cause both the stream and the
+/// buffer to get destroyed.
+pub fn write<T>(rid: ResourceId, buf: T) -> Write<T>
+where
+  T: AsRef<[u8]>,
+{
+  Write {
+    rid,
+    buf,
+    state: IoState::Pending,
+  }
+}
+
+/// This is almost the same implementation as in tokio, difference is
+/// that error type is `ErrBox` instead of `std::io::Error`.
+impl<T> Future for Write<T>
+where
+  T: AsRef<[u8]>,
+{
+  type Item = usize;
+  type Error = ErrBox;
+
+  fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+    if self.state == IoState::Done {
+      panic!("poll a Read after it's done");
+    }
+
+    let mut table = resources::lock_resource_table();
+    let resource = table
+      .get_mut::<CliResource>(self.rid)
+      .ok_or_else(bad_resource)?;
+    let nwritten = try_ready!(resource.poll_write(self.buf.as_ref()));
+    self.state = IoState::Done;
+    Ok(nwritten.into())
   }
 }
 
@@ -41,12 +144,9 @@ pub fn op_write(rid: i32, zero_copy: Option<PinnedBuf>) -> Box<MinimalOp> {
     Some(buf) => buf,
   };
 
-  match resources::lookup(rid as u32) {
-    Err(e) => Box::new(futures::future::err(e)),
-    Ok(resource) => Box::new(
-      tokio_write::write(resource, zero_copy)
-        .map_err(ErrBox::from)
-        .and_then(move |(_resource, _buf, nwritten)| Ok(nwritten as i32)),
-    ),
-  }
+  let fut = write(rid as u32, zero_copy)
+    .map_err(ErrBox::from)
+    .and_then(move |nwritten| Ok(nwritten as i32));
+
+  Box::new(fut)
 }
diff --git a/cli/ops/net.rs b/cli/ops/net.rs
index d603b746b..a4b3bf934 100644
--- a/cli/ops/net.rs
+++ b/cli/ops/net.rs
@@ -4,7 +4,7 @@ use crate::deno_error::bad_resource;
 use crate::ops::json_op;
 use crate::resolve_addr::resolve_addr;
 use crate::resources;
-use crate::resources::CoreResource;
+use crate::resources::CliResource;
 use crate::resources::Resource;
 use crate::state::ThreadSafeState;
 use deno::*;
@@ -132,13 +132,13 @@ fn op_accept(
     .and_then(move |(tcp_stream, _socket_addr)| {
       let local_addr = tcp_stream.local_addr()?;
       let remote_addr = tcp_stream.peer_addr()?;
-      let tcp_stream_resource = resources::add_tcp_stream(tcp_stream);
-      Ok((tcp_stream_resource, local_addr, remote_addr))
+      let rid = resources::add_tcp_stream(tcp_stream);
+      Ok((rid, local_addr, remote_addr))
     })
     .map_err(ErrBox::from)
-    .and_then(move |(tcp_stream_resource, local_addr, remote_addr)| {
+    .and_then(move |(rid, local_addr, remote_addr)| {
       futures::future::ok(json!({
-        "rid": tcp_stream_resource.rid,
+        "rid": rid,
         "localAddr": local_addr.to_string(),
         "remoteAddr": remote_addr.to_string(),
       }))
@@ -170,13 +170,13 @@ fn op_dial(
       .and_then(move |tcp_stream| {
         let local_addr = tcp_stream.local_addr()?;
         let remote_addr = tcp_stream.peer_addr()?;
-        let tcp_stream_resource = resources::add_tcp_stream(tcp_stream);
-        Ok((tcp_stream_resource, local_addr, remote_addr))
+        let rid = resources::add_tcp_stream(tcp_stream);
+        Ok((rid, local_addr, remote_addr))
       })
       .map_err(ErrBox::from)
-      .and_then(move |(tcp_stream_resource, local_addr, remote_addr)| {
+      .and_then(move |(rid, local_addr, remote_addr)| {
         futures::future::ok(json!({
-          "rid": tcp_stream_resource.rid,
+          "rid": rid,
           "localAddr": local_addr.to_string(),
           "remoteAddr": remote_addr.to_string(),
         }))
@@ -201,7 +201,6 @@ fn op_shutdown(
 
   let rid = args.rid as u32;
   let how = args.how;
-  let mut resource = resources::lookup(rid)?;
 
   let shutdown_mode = match how {
     0 => Shutdown::Read,
@@ -209,8 +208,15 @@ fn op_shutdown(
     _ => unimplemented!(),
   };
 
-  // Use UFCS for disambiguation
-  Resource::shutdown(&mut resource, shutdown_mode)?;
+  let mut table = resources::lock_resource_table();
+  let resource = table.get_mut::<CliResource>(rid).ok_or_else(bad_resource)?;
+  match resource {
+    CliResource::TcpStream(ref mut stream) => {
+      TcpStream::shutdown(stream, shutdown_mode).map_err(ErrBox::from)?;
+    }
+    _ => return Err(bad_resource()),
+  }
+
   Ok(JsonOp::Sync(json!({})))
 }
 
@@ -228,7 +234,7 @@ struct TcpListenerResource {
   local_addr: SocketAddr,
 }
 
-impl CoreResource for TcpListenerResource {}
+impl Resource for TcpListenerResource {}
 
 impl Drop for TcpListenerResource {
   fn drop(&mut self) {
diff --git a/cli/ops/repl.rs b/cli/ops/repl.rs
index ba63c5109..723fb2571 100644
--- a/cli/ops/repl.rs
+++ b/cli/ops/repl.rs
@@ -5,7 +5,7 @@ use crate::ops::json_op;
 use crate::repl;
 use crate::repl::Repl;
 use crate::resources;
-use crate::resources::CoreResource;
+use crate::resources::Resource;
 use crate::state::ThreadSafeState;
 use deno::*;
 use std::sync::Arc;
@@ -24,7 +24,7 @@ pub fn init(i: &mut Isolate, s: &ThreadSafeState) {
 
 struct ReplResource(Arc<Mutex<Repl>>);
 
-impl CoreResource for ReplResource {}
+impl Resource for ReplResource {}
 
 #[derive(Deserialize)]
 #[serde(rename_all = "camelCase")]
diff --git a/cli/ops/tls.rs b/cli/ops/tls.rs
index ee08f357a..6e8348c91 100644
--- a/cli/ops/tls.rs
+++ b/cli/ops/tls.rs
@@ -6,7 +6,7 @@ use crate::deno_error::ErrorKind;
 use crate::ops::json_op;
 use crate::resolve_addr::resolve_addr;
 use crate::resources;
-use crate::resources::CoreResource;
+use crate::resources::Resource;
 use crate::state::ThreadSafeState;
 use deno::*;
 use futures::Async;
@@ -99,9 +99,9 @@ pub fn op_dial_tls(
             .connect(dnsname, tcp_stream)
             .map_err(ErrBox::from)
             .and_then(move |tls_stream| {
-              let tls_stream_resource = resources::add_tls_stream(tls_stream);
+              let rid = resources::add_tls_stream(tls_stream);
               futures::future::ok(json!({
-                "rid": tls_stream_resource.rid,
+                "rid": rid,
                 "localAddr": local_addr.to_string(),
                 "remoteAddr": remote_addr.to_string(),
               }))
@@ -179,7 +179,7 @@ pub struct TlsListenerResource {
   local_addr: SocketAddr,
 }
 
-impl CoreResource for TlsListenerResource {}
+impl Resource for TlsListenerResource {}
 
 impl Drop for TlsListenerResource {
   fn drop(&mut self) {
@@ -389,14 +389,13 @@ fn op_accept_tls(
         .accept(tcp_stream)
         .map_err(ErrBox::from)
         .and_then(move |tls_stream| {
-          let tls_stream_resource =
-            resources::add_server_tls_stream(tls_stream);
-          Ok((tls_stream_resource, local_addr, remote_addr))
+          let rid = resources::add_server_tls_stream(tls_stream);
+          Ok((rid, local_addr, remote_addr))
         })
     })
-    .and_then(move |(tls_stream_resource, local_addr, remote_addr)| {
+    .and_then(move |(rid, local_addr, remote_addr)| {
       futures::future::ok(json!({
-        "rid": tls_stream_resource.rid,
+        "rid": rid,
         "localAddr": local_addr.to_string(),
         "remoteAddr": remote_addr.to_string(),
       }))
diff --git a/cli/resources.rs b/cli/resources.rs
index 3b070e06b..2e6306761 100644
--- a/cli/resources.rs
+++ b/cli/resources.rs
@@ -8,11 +8,10 @@
 // descriptors". This module implements a global resource table. Ops (AKA
 // handlers) look up resources by their integer id here.
 
-use crate::deno_error;
 use crate::deno_error::bad_resource;
 use crate::http_body::HttpBody;
 use deno::ErrBox;
-pub use deno::Resource as CoreResource;
+pub use deno::Resource;
 pub use deno::ResourceId;
 use deno::ResourceTable;
 
@@ -21,8 +20,6 @@ use futures::Future;
 use futures::Poll;
 use reqwest::r#async::Decoder as ReqwestDecoder;
 use std;
-use std::io::{Read, Seek, SeekFrom, Write};
-use std::net::Shutdown;
 use std::process::ExitStatus;
 use std::sync::Mutex;
 use std::sync::MutexGuard;
@@ -66,7 +63,7 @@ lazy_static! {
 }
 
 // TODO: move listeners out of this enum and rename to `StreamResource`
-enum CliResource {
+pub enum CliResource {
   Stdin(tokio::io::Stdin),
   Stdout(tokio::fs::File),
   Stderr(tokio::io::Stderr),
@@ -84,60 +81,21 @@ enum CliResource {
   ChildStderr(tokio_process::ChildStderr),
 }
 
-impl CoreResource for CliResource {}
+impl Resource for CliResource {}
 
 pub fn lock_resource_table<'a>() -> MutexGuard<'a, ResourceTable> {
   RESOURCE_TABLE.lock().unwrap()
 }
 
-// Abstract async file interface.
-// Ideally in unix, if Resource represents an OS rid, it will be the same.
-#[derive(Clone, Debug)]
-pub struct Resource {
-  pub rid: ResourceId,
-}
-
-impl Resource {
-  // close(2) is done by dropping the value. Therefore we just need to remove
-  // the resource from the RESOURCE_TABLE.
-  pub fn close(&self) {
-    let mut table = lock_resource_table();
-    table.close(self.rid).unwrap();
-  }
-
-  pub fn shutdown(&mut self, how: Shutdown) -> Result<(), ErrBox> {
-    let mut table = lock_resource_table();
-    let repr = table
-      .get_mut::<CliResource>(self.rid)
-      .ok_or_else(bad_resource)?;
-
-    match repr {
-      CliResource::TcpStream(ref mut f) => {
-        TcpStream::shutdown(f, how).map_err(ErrBox::from)
-      }
-      _ => Err(bad_resource()),
-    }
-  }
-}
-
-impl Read for Resource {
-  fn read(&mut self, _buf: &mut [u8]) -> std::io::Result<usize> {
-    unimplemented!();
-  }
-}
-
 /// `DenoAsyncRead` is the same as the `tokio_io::AsyncRead` trait
 /// but uses an `ErrBox` error instead of `std::io:Error`
 pub trait DenoAsyncRead {
   fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, ErrBox>;
 }
 
-impl DenoAsyncRead for Resource {
+impl DenoAsyncRead for CliResource {
   fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, ErrBox> {
-    let mut table = lock_resource_table();
-    let repr = table.get_mut(self.rid).ok_or_else(bad_resource)?;
-
-    let r = match repr {
+    let r = match self {
       CliResource::FsFile(ref mut f) => f.poll_read(buf),
       CliResource::Stdin(ref mut f) => f.poll_read(buf),
       CliResource::TcpStream(ref mut f) => f.poll_read(buf),
@@ -155,16 +113,6 @@ impl DenoAsyncRead for Resource {
   }
 }
 
-impl Write for Resource {
-  fn write(&mut self, _buf: &[u8]) -> std::io::Result<usize> {
-    unimplemented!()
-  }
-
-  fn flush(&mut self) -> std::io::Result<()> {
-    unimplemented!()
-  }
-}
-
 /// `DenoAsyncWrite` is the same as the `tokio_io::AsyncWrite` trait
 /// but uses an `ErrBox` error instead of `std::io:Error`
 pub trait DenoAsyncWrite {
@@ -173,14 +121,9 @@ pub trait DenoAsyncWrite {
   fn shutdown(&mut self) -> Poll<(), ErrBox>;
 }
 
-impl DenoAsyncWrite for Resource {
+impl DenoAsyncWrite for CliResource {
   fn poll_write(&mut self, buf: &[u8]) -> Poll<usize, ErrBox> {
-    let mut table = lock_resource_table();
-    let repr = table
-      .get_mut::<CliResource>(self.rid)
-      .ok_or_else(bad_resource)?;
-
-    let r = match repr {
+    let r = match self {
       CliResource::FsFile(ref mut f) => f.poll_write(buf),
       CliResource::Stdout(ref mut f) => f.poll_write(buf),
       CliResource::Stderr(ref mut f) => f.poll_write(buf),
@@ -201,41 +144,36 @@ impl DenoAsyncWrite for Resource {
   }
 }
 
-pub fn add_fs_file(fs_file: tokio::fs::File) -> Resource {
+pub fn add_fs_file(fs_file: tokio::fs::File) -> ResourceId {
   let mut table = lock_resource_table();
-  let rid = table.add("fsFile", Box::new(CliResource::FsFile(fs_file)));
-  Resource { rid }
+  table.add("fsFile", Box::new(CliResource::FsFile(fs_file)))
 }
 
-pub fn add_tcp_stream(stream: tokio::net::TcpStream) -> Resource {
+pub fn add_tcp_stream(stream: tokio::net::TcpStream) -> ResourceId {
   let mut table = lock_resource_table();
-  let rid = table.add("tcpStream", Box::new(CliResource::TcpStream(stream)));
-  Resource { rid }
+  table.add("tcpStream", Box::new(CliResource::TcpStream(stream)))
 }
 
-pub fn add_tls_stream(stream: ClientTlsStream<TcpStream>) -> Resource {
+pub fn add_tls_stream(stream: ClientTlsStream<TcpStream>) -> ResourceId {
   let mut table = lock_resource_table();
-  let rid = table.add(
+  table.add(
     "clientTlsStream",
     Box::new(CliResource::ClientTlsStream(Box::new(stream))),
-  );
-  Resource { rid }
+  )
 }
 
-pub fn add_server_tls_stream(stream: ServerTlsStream<TcpStream>) -> Resource {
+pub fn add_server_tls_stream(stream: ServerTlsStream<TcpStream>) -> ResourceId {
   let mut table = lock_resource_table();
-  let rid = table.add(
+  table.add(
     "serverTlsStream",
     Box::new(CliResource::ServerTlsStream(Box::new(stream))),
-  );
-  Resource { rid }
+  )
 }
 
-pub fn add_reqwest_body(body: ReqwestDecoder) -> Resource {
+pub fn add_reqwest_body(body: ReqwestDecoder) -> ResourceId {
   let body = HttpBody::from(body);
   let mut table = lock_resource_table();
-  let rid = table.add("httpBody", Box::new(CliResource::HttpBody(body)));
-  Resource { rid }
+  table.add("httpBody", Box::new(CliResource::HttpBody(body)))
 }
 
 pub struct ChildResources {
@@ -347,40 +285,3 @@ pub fn get_file(rid: ResourceId) -> Result<std::fs::File, ErrBox> {
     _ => Err(bad_resource()),
   }
 }
-
-pub fn lookup(rid: ResourceId) -> Result<Resource, ErrBox> {
-  debug!("resource lookup {}", rid);
-  let table = lock_resource_table();
-  let _ = table.get::<CliResource>(rid).ok_or_else(bad_resource)?;
-  Ok(Resource { rid })
-}
-
-pub fn seek(
-  resource: Resource,
-  offset: i32,
-  whence: u32,
-) -> Box<dyn Future<Item = (), Error = ErrBox> + Send> {
-  // Translate seek mode to Rust repr.
-  let seek_from = match whence {
-    0 => SeekFrom::Start(offset as u64),
-    1 => SeekFrom::Current(i64::from(offset)),
-    2 => SeekFrom::End(i64::from(offset)),
-    _ => {
-      return Box::new(futures::future::err(
-        deno_error::DenoError::new(
-          deno_error::ErrorKind::InvalidSeekMode,
-          format!("Invalid seek mode: {}", whence),
-        )
-        .into(),
-      ));
-    }
-  };
-
-  match get_file(resource.rid) {
-    Ok(mut file) => Box::new(futures::future::lazy(move || {
-      let result = file.seek(seek_from).map(|_| {}).map_err(ErrBox::from);
-      futures::future::result(result)
-    })),
-    Err(err) => Box::new(futures::future::err(err)),
-  }
-}
diff --git a/cli/tokio_read.rs b/cli/tokio_read.rs
deleted file mode 100644
index 25c4df191..000000000
--- a/cli/tokio_read.rs
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright (c) 2019 Tokio Contributors. All rights reserved. MIT license.
-// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-// Forked from: https://github.com/tokio-rs/tokio/blob/9b3f8564af4bb1aee07fab3c401eb412ca5eeac5/tokio-io/src/io/read.rs
-use crate::resources::DenoAsyncRead;
-use deno::ErrBox;
-use futures::{Future, Poll};
-use std::mem;
-
-/// This is almost the same implementation as in tokio, the only difference is
-/// that error type is `ErrBox` instead of `std::io::Error`.
-
-#[derive(Debug)]
-enum State<R, T> {
-  Pending { rd: R, buf: T },
-  Empty,
-}
-
-/// Tries to read some bytes directly into the given `buf` in asynchronous
-/// manner, returning a future type.
-///
-/// The returned future will resolve to both the I/O stream and the buffer
-/// as well as the number of bytes read once the read operation is completed.
-pub fn read<R, T>(rd: R, buf: T) -> Read<R, T>
-where
-  R: DenoAsyncRead,
-  T: AsMut<[u8]>,
-{
-  Read {
-    state: State::Pending { rd, buf },
-  }
-}
-
-/// A future which can be used to easily read available number of bytes to fill
-/// a buffer.
-///
-/// Created by the [`read`] function.
-#[derive(Debug)]
-pub struct Read<R, T> {
-  state: State<R, T>,
-}
-
-impl<R, T> Future for Read<R, T>
-where
-  R: DenoAsyncRead,
-  T: AsMut<[u8]>,
-{
-  type Item = (R, T, usize);
-  type Error = ErrBox;
-
-  fn poll(&mut self) -> Poll<(R, T, usize), ErrBox> {
-    let nread = match self.state {
-      State::Pending {
-        ref mut rd,
-        ref mut buf,
-      } => try_ready!(rd.poll_read(&mut buf.as_mut()[..])),
-      State::Empty => panic!("poll a Read after it's done"),
-    };
-
-    match mem::replace(&mut self.state, State::Empty) {
-      State::Pending { rd, buf } => Ok((rd, buf, nread).into()),
-      State::Empty => panic!("invalid internal state"),
-    }
-  }
-}
diff --git a/cli/tokio_write.rs b/cli/tokio_write.rs
deleted file mode 100644
index 31b4cda30..000000000
--- a/cli/tokio_write.rs
+++ /dev/null
@@ -1,62 +0,0 @@
-// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-use crate::resources::DenoAsyncWrite;
-use deno::ErrBox;
-use futures::{Future, Poll};
-use std::mem;
-
-/// A future used to write some data to a stream.
-///
-/// This is created by the [`write`] top-level method.
-///
-/// [`write`]: fn.write.html
-#[derive(Debug)]
-pub struct Write<A, T> {
-  state: State<A, T>,
-}
-
-#[derive(Debug)]
-enum State<A, T> {
-  Pending { a: A, buf: T },
-  Empty,
-}
-
-/// Creates a future that will write some of the buffer `buf` to
-/// the stream `a` provided.
-///
-/// Any error which happens during writing will cause both the stream and the
-/// buffer to get destroyed.
-pub fn write<A, T>(a: A, buf: T) -> Write<A, T>
-where
-  A: DenoAsyncWrite,
-  T: AsRef<[u8]>,
-{
-  Write {
-    state: State::Pending { a, buf },
-  }
-}
-
-/// This is almost the same implementation as in tokio, difference is
-/// that error type is `ErrBox` instead of `std::io::Error`.
-impl<A, T> Future for Write<A, T>
-where
-  A: DenoAsyncWrite,
-  T: AsRef<[u8]>,
-{
-  type Item = (A, T, usize);
-  type Error = ErrBox;
-
-  fn poll(&mut self) -> Poll<(A, T, usize), ErrBox> {
-    let nwritten = match self.state {
-      State::Pending {
-        ref mut a,
-        ref mut buf,
-      } => try_ready!(a.poll_write(buf.as_ref())),
-      State::Empty => panic!("poll a Read after it's done"),
-    };
-
-    match mem::replace(&mut self.state, State::Empty) {
-      State::Pending { a, buf } => Ok((a, buf, nwritten).into()),
-      State::Empty => panic!("invalid internal state"),
-    }
-  }
-}
diff --git a/cli/worker.rs b/cli/worker.rs
index 6b4970015..eeda364c9 100644
--- a/cli/worker.rs
+++ b/cli/worker.rs
@@ -3,7 +3,7 @@ use crate::deno_error::bad_resource;
 use crate::fmt_errors::JSError;
 use crate::ops;
 use crate::resources;
-use crate::resources::CoreResource;
+use crate::resources::Resource;
 use crate::resources::ResourceId;
 use crate::state::ThreadSafeState;
 use deno;
@@ -31,7 +31,7 @@ pub struct WorkerChannels {
   pub receiver: mpsc::Receiver<Buf>,
 }
 
-impl CoreResource for WorkerChannels {}
+impl Resource for WorkerChannels {}
 
 /// Wraps deno::Isolate to provide source maps, ops for the CLI, and
 /// high-level module loading.
@@ -374,12 +374,9 @@ mod tests {
       worker.execute(source).unwrap();
 
       let worker_ = worker.clone();
-      let rid = worker.state.rid;
-      let resource_ = resources::Resource { rid };
 
       tokio::spawn(lazy(move || {
         worker.then(move |r| -> Result<(), ()> {
-          resource_.close();
           r.unwrap();
           Ok(())
         })
@@ -413,12 +410,10 @@ mod tests {
         .unwrap();
 
       let rid = worker.state.rid;
-      let resource = resources::Resource { rid };
       let worker_ = worker.clone();
 
       let worker_future = worker
         .then(move |r| -> Result<(), ()> {
-          resource.close();
           println!("workers.rs after resource close");
           r.unwrap();
           Ok(())