Add deflate protocol (#1146)

protocols/deflate/src/lib.rs

@@ -0,0 +1,76 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+use flate2::read::DeflateDecoder;
+use flate2::write::DeflateEncoder;
+use flate2::Compression;
+use std::io;
+
+use futures::future::{self, FutureResult};
+use libp2p_core::{upgrade::Negotiated, InboundUpgrade, OutboundUpgrade, UpgradeInfo};
+use std::iter;
+use tokio_io::{AsyncRead, AsyncWrite};
+
+#[derive(Debug, Copy, Clone)]
+pub struct DeflateConfig;
+
+/// Output of the deflate protocol.
+pub type DeflateOutput<S> = DeflateDecoder<DeflateEncoder<S>>;
+
+impl UpgradeInfo for DeflateConfig {
+    type Info = &'static [u8];
+    type InfoIter = iter::Once<Self::Info>;
+
+    fn protocol_info(&self) -> Self::InfoIter {
+        iter::once(b"/deflate/1.0.0")
+    }
+}
+
+impl<C> InboundUpgrade<C> for DeflateConfig
+where
+    C: AsyncRead + AsyncWrite,
+{
+    type Output = DeflateOutput<Negotiated<C>>;
+    type Error = io::Error;
+    type Future = FutureResult<Self::Output, Self::Error>;
+
+    fn upgrade_inbound(self, r: Negotiated<C>, _: Self::Info) -> Self::Future {
+        future::ok(DeflateDecoder::new(DeflateEncoder::new(
+            r,
+            Compression::default(),
+        )))
+    }
+}
+
+impl<C> OutboundUpgrade<C> for DeflateConfig
+where
+    C: AsyncRead + AsyncWrite,
+{
+    type Output = DeflateOutput<Negotiated<C>>;
+    type Error = io::Error;
+    type Future = FutureResult<Self::Output, Self::Error>;
+
+    fn upgrade_outbound(self, w: Negotiated<C>, _: Self::Info) -> Self::Future {
+        future::ok(DeflateDecoder::new(DeflateEncoder::new(
+            w,
+            Compression::default(),
+        )))
+    }
+}