1 files changed, 89 insertions, 0 deletions
diff --git a/cli/http_body.rs b/cli/http_body.rs
new file mode 100644
index 000000000..c03dfd637
--- /dev/null
+++ b/cli/http_body.rs
@@ -0,0 +1,89 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+use futures::stream::Stream;
+use futures::Async;
+use futures::Poll;
+use reqwest::r#async::Chunk;
+use reqwest::r#async::Decoder;
+use std::cmp::min;
+use std::io;
+use std::io::Read;
+use tokio::io::AsyncRead;
+
+/// Wraps `reqwest::Decoder` so that it can be exposed as an `AsyncRead` and integrated
+/// into resources more easily.
+pub struct HttpBody {
+  decoder: Decoder,
+  chunk: Option<Chunk>,
+  pos: usize,
+}
+
+impl HttpBody {
+  pub fn from(body: Decoder) -> Self {
+    Self {
+      decoder: body,
+      chunk: None,
+      pos: 0,
+    }
+  }
+}
+
+impl Read for HttpBody {
+  fn read(&mut self, _buf: &mut [u8]) -> io::Result<usize> {
+    unimplemented!();
+  }
+}
+
+impl AsyncRead for HttpBody {
+  fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, io::Error> {
+    if let Some(chunk) = self.chunk.take() {
+      debug!(
+        "HttpBody Fake Read buf {} chunk {} pos {}",
+        buf.len(),
+        chunk.len(),
+        self.pos
+      );
+      let n = min(buf.len(), chunk.len() - self.pos);
+      {
+        let rest = &chunk[self.pos..];
+        buf[..n].clone_from_slice(&rest[..n]);
+      }
+      self.pos += n;
+      if self.pos == chunk.len() {
+        self.pos = 0;
+      } else {
+        self.chunk = Some(chunk);
+      }
+      return Ok(Async::Ready(n));
+    } else {
+      assert_eq!(self.pos, 0);
+    }
+
+    let p = self.decoder.poll();
+    match p {
+      Err(e) => Err(
+        // TODO Need to map hyper::Error into std::io::Error.
+        io::Error::new(io::ErrorKind::Other, e),
+      ),
+      Ok(Async::NotReady) => Ok(Async::NotReady),
+      Ok(Async::Ready(maybe_chunk)) => match maybe_chunk {
+        None => Ok(Async::Ready(0)),
+        Some(chunk) => {
+          debug!(
+            "HttpBody Real Read buf {} chunk {} pos {}",
+            buf.len(),
+            chunk.len(),
+            self.pos
+          );
+          let n = min(buf.len(), chunk.len());
+          buf[..n].clone_from_slice(&chunk[..n]);
+          if buf.len() < chunk.len() {
+            self.pos = n;
+            self.chunk = Some(chunk);
+          }
+          Ok(Async::Ready(n))
+        }
+      },
+    }
+  }
+}