Move code from sc-network-common back to sc-network (#13592)

* Move service tests to `client/network/tests`

These tests depend on `sc-network` and `sc-network-sync` so they should
live outside the crate.

* Move some configs from `sc-network-common` to `sc-network`

* Move `NetworkService` traits to `sc-network`

* Move request-responses to `sc-network`

* Remove more stuff

* Remove rest of configs from `sc-network-common` to `sc-network`

* Remove more stuff

* Fix warnings

* Update client/network/src/request_responses.rs

Co-authored-by: Dmitry Markin <dmitry@markin.tech>

* Fix cargo doc

---------

Co-authored-by: Dmitry Markin <dmitry@markin.tech>

substrate/client/network/src/event.rs

@@ -0,0 +1,92 @@
+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+//! Network event types. These are are not the part of the protocol, but rather
+//! events that happen on the network like DHT get/put results received.
+
+use crate::types::ProtocolName;
+
+use bytes::Bytes;
+use libp2p::{core::PeerId, kad::record::Key};
+
+use sc_network_common::role::ObservedRole;
+
+/// Events generated by DHT as a response to get_value and put_value requests.
+#[derive(Debug, Clone)]
+#[must_use]
+pub enum DhtEvent {
+	/// The value was found.
+	ValueFound(Vec<(Key, Vec<u8>)>),
+
+	/// The requested record has not been found in the DHT.
+	ValueNotFound(Key),
+
+	/// The record has been successfully inserted into the DHT.
+	ValuePut(Key),
+
+	/// An error has occurred while putting a record into the DHT.
+	ValuePutFailed(Key),
+}
+
+/// Type for events generated by networking layer.
+#[derive(Debug, Clone)]
+#[must_use]
+pub enum Event {
+	/// Event generated by a DHT.
+	Dht(DhtEvent),
+
+	/// Opened a substream with the given node with the given notifications protocol.
+	///
+	/// The protocol is always one of the notification protocols that have been registered.
+	NotificationStreamOpened {
+		/// Node we opened the substream with.
+		remote: PeerId,
+		/// The concerned protocol. Each protocol uses a different substream.
+		/// This is always equal to the value of
+		/// `sc_network::config::NonDefaultSetConfig::notifications_protocol` of one of the
+		/// configured sets.
+		protocol: ProtocolName,
+		/// If the negotiation didn't use the main name of the protocol (the one in
+		/// `notifications_protocol`), then this field contains which name has actually been
+		/// used.
+		/// Always contains a value equal to the value in
+		/// `sc_network::config::NonDefaultSetConfig::fallback_names`.
+		negotiated_fallback: Option<ProtocolName>,
+		/// Role of the remote.
+		role: ObservedRole,
+		/// Received handshake.
+		received_handshake: Vec<u8>,
+	},
+
+	/// Closed a substream with the given node. Always matches a corresponding previous
+	/// `NotificationStreamOpened` message.
+	NotificationStreamClosed {
+		/// Node we closed the substream with.
+		remote: PeerId,
+		/// The concerned protocol. Each protocol uses a different substream.
+		protocol: ProtocolName,
+	},
+
+	/// Received one or more messages from the given node using the given protocol.
+	NotificationsReceived {
+		/// Node we received the message from.
+		remote: PeerId,
+		/// Concerned protocol and associated message.
+		messages: Vec<(ProtocolName, Bytes)>,
+	},
+}