Move protos to a separate crate (#247)

* Move protos to a separate crate

Makes Raft a workspace project

Signed-off-by: Nick Cameron <nrc@ncameron.org>

* Satisfy Rustfmt

Signed-off-by: Nick Cameron <nrc@ncameron.org>

Cargo.toml

@@ -11,14 +11,12 @@ documentation = "https://docs.rs/raft"
 description = "The rust language implementation of Raft algorithm."
 categories = ["algorithms", "database-implementations"]
 edition = "2018"
-build = "build.rs"
 
-[build-dependencies]
-protobuf-build = "0.6"
+[workspace]
+members = ["proto"]
 
 [features]
 default = []
-gen = []
 # Enable failpoints
 failpoint = ["fail"]
 
@@ -32,6 +30,7 @@ prost-derive = "0.5"
 bytes = "0.4.11"
 slog = "2.2"
 quick-error = "1.2.2"
+raft-proto = { path = "proto" }
 rand = "0.6.4"
 hashbrown = "0.3"
 fail = { version = "0.2", optional = true }

harness/src/lib.rs

@@ -42,7 +42,6 @@ mod network;
 pub use self::{interface::Interface, network::Network};
 use slog::{Drain, Logger};
 
-
 /// Build a logger for tests.
 ///
 /// Currently, this is a terminal log. It ensures it is only initialized once to prevent clobbering.

proto/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "raft-proto"
+version = "0.1.0"
+authors = ["The TiKV Project Developers"]
+edition = "2018"
+license = "Apache-2.0"
+keywords = ["raft", "distributed-systems", "ha"]
+repository = "https://github.com/pingcap/raft-rs"
+homepage = "https://github.com/pingcap/raft-rs"
+documentation = "https://docs.rs/raft-proto"
+description = "Protocol definitions for the rust language implementation of the Raft algorithm."
+categories = ["algorithms", "database-implementations"]
+build = "build.rs"
+
+[features]
+default = []
+gen = []
+
+[build-dependencies]
+protobuf-build = "0.6"
+
+[dependencies]
+bytes = "0.4.11"
+lazy_static = "1.3.0"
+prost = "0.5"
+prost-derive = "0.5"
+protobuf = "2"

build.rs → proto/build.rs

@@ -1,15 +1,4 @@
-// Copyright 2019 PingCAP, Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// See the License for the specific language governing permissions and
-// limitations under the License.
+// Copyright 2019 TiKV Project Authors. Licensed under Apache-2.0.
 
 use protobuf_build::*;
 use std::fs::{read_dir, File};
@@ -44,7 +33,7 @@ fn main() {
         println!("cargo:rerun-if-changed={}", f);
     }
 
-    // Generate Prost files.
+    // Generate Prost output.
     generate_prost_files(&file_names, "src/prost");
     let mod_names = module_names_for_dir("src/prost");
     generate_wrappers(

proto/src/lib.rs

@@ -0,0 +1,48 @@
+// Copyright 2019 TiKV Project Authors. Licensed under Apache-2.0.
+
+pub use crate::prost::eraftpb;
+
+mod prost;
+
+pub mod prelude {
+    pub use crate::eraftpb::{
+        ConfChange, ConfChangeType, ConfState, Entry, EntryType, HardState, Message, MessageType,
+        Snapshot, SnapshotMetadata,
+    };
+}
+
+pub mod util {
+    use crate::eraftpb::{ConfChange, ConfChangeType, ConfState};
+
+    // Bring some consistency to things. The protobuf has `nodes` and it's not really a term that's used anymore.
+    impl ConfState {
+        /// Get the voters. This is identical to `nodes`.
+        #[inline]
+        pub fn get_voters(&self) -> &[u64] {
+            &self.nodes
+        }
+    }
+
+    impl<Iter1, Iter2> From<(Iter1, Iter2)> for ConfState
+    where
+        Iter1: IntoIterator<Item = u64>,
+        Iter2: IntoIterator<Item = u64>,
+    {
+        fn from((voters, learners): (Iter1, Iter2)) -> Self {
+            let mut conf_state = ConfState::default();
+            conf_state.mut_nodes().extend(voters.into_iter());
+            conf_state.mut_learners().extend(learners.into_iter());
+            conf_state
+        }
+    }
+
+    impl From<(u64, ConfState)> for ConfChange {
+        fn from((start_index, state): (u64, ConfState)) -> Self {
+            let mut change = ConfChange::default();
+            change.set_change_type(ConfChangeType::BeginMembershipChange);
+            change.set_configuration(state);
+            change.set_start_index(start_index);
+            change
+        }
+    }
+}

src/lib.rs

@@ -382,10 +382,6 @@ extern crate quick_error;
 extern crate getset;
 
 mod config;
-mod prost;
-/// This module supplies the needed message types. However, it is autogenerated and thus cannot be
-/// documented by field.
-pub use crate::prost::eraftpb;
 mod errors;
 mod log_unstable;
 mod progress;
@@ -412,6 +408,7 @@ pub use self::raw_node::{is_empty_snap, Peer, RawNode, Ready, SnapshotStatus};
 pub use self::read_only::{ReadOnlyOption, ReadState};
 pub use self::status::Status;
 pub use self::storage::{RaftState, Storage};
+pub use raft_proto::eraftpb;
 use slog::{Drain, Logger};
 
 pub mod prelude {
@@ -427,10 +424,7 @@ pub mod prelude {
     //!
     //! The prelude may grow over time as additional items see ubiquitous use.
 
-    pub use crate::eraftpb::{
-        ConfChange, ConfChangeType, ConfState, Entry, EntryType, HardState, Message, MessageType,
-        Snapshot, SnapshotMetadata,
-    };
+    pub use raft_proto::prelude::*;
 
     pub use crate::config::Config;
     pub use crate::raft::Raft;

src/util.rs

@@ -16,7 +16,7 @@
 
 use std::u64;
 
-use crate::eraftpb::{ConfChange, ConfChangeType, ConfState, Entry, Message};
+use crate::eraftpb::{Entry, Message};
 use prost::Message as ProstMsg;
 
 /// A number to represent that there is no limit.
@@ -79,38 +79,6 @@ pub fn limit_size<T: ProstMsg + Clone>(entries: &mut Vec<T>, max: Option<u64>) {
     entries.truncate(limit);
 }
 
-// Bring some consistency to things. The protobuf has `nodes` and it's not really a term that's used anymore.
-impl ConfState {
-    /// Get the voters. This is identical to `nodes`.
-    #[inline]
-    pub fn get_voters(&self) -> &[u64] {
-        &self.nodes
-    }
-}
-
-impl<Iter1, Iter2> From<(Iter1, Iter2)> for ConfState
-where
-    Iter1: IntoIterator<Item = u64>,
-    Iter2: IntoIterator<Item = u64>,
-{
-    fn from((voters, learners): (Iter1, Iter2)) -> Self {
-        let mut conf_state = ConfState::default();
-        conf_state.mut_nodes().extend(voters.into_iter());
-        conf_state.mut_learners().extend(learners.into_iter());
-        conf_state
-    }
-}
-
-impl From<(u64, ConfState)> for ConfChange {
-    fn from((start_index, state): (u64, ConfState)) -> Self {
-        let mut change = ConfChange::default();
-        change.set_change_type(ConfChangeType::BeginMembershipChange);
-        change.set_configuration(state);
-        change.set_start_index(start_index);
-        change
-    }
-}
-
 /// Check whether the entry is continuous to the message.
 /// i.e msg's next entry index should be equal to the first entries's index
 pub fn is_continuous_ents(msg: &Message, ents: &[Entry]) -> bool {