Extract Network and Interface from utils (#127)

* Extract Network and Interface from utils

* Use a component

* fmt

* Remove unnecessary dev-dep

* fmt

* extract setup_for_test

Signed-off-by: Ana Hobden <operator@hoverbear.org>

* Fmt

Signed-off-by: Ana Hobden <operator@hoverbear.org>

* Fixup failpoint test

Signed-off-by: Ana Hobden <operator@hoverbear.org>

* Fmt

Signed-off-by: Ana Hobden <operator@hoverbear.org>

.gitignore

@@ -25,6 +25,8 @@ target
 tmp
 /bin
 
+harness/target
+
 Cargo.lock
 *.rs.bk
 *.rs.fmt

Cargo.toml

@@ -13,8 +13,10 @@ categories = ["algorithms", "database-implementations"]
 
 [features]
 default = []
+# Enable failpoints
 failpoint = ["fail"]
 
+# Make sure to synchronize updates with Harness.
 [dependencies]
 log = ">0.2"
 protobuf = "~2.0-2.2"
@@ -28,6 +30,7 @@ getset = "0.0.6"
 env_logger = "0.5"
 criterion = ">0.2.4"
 lazy_static = "1.0"
+harness = { path = "harness" }
 regex = "1.1"
 
 [[bench]]

harness/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "harness"
+version = "0.1.0"
+authors = ["The TiKV Project Developers"]
+license = "Apache-2.0"
+keywords = []
+repository = "https://github.com/pingcap/raft-rs/harness"
+readme = "README.md"
+homepage = "https://github.com/pingcap/raft-rs/harness"
+description = "A testing harness for Raft."
+categories = []
+
+# Make sure to synchronize updates with Raft.
+[dependencies]
+raft = { path = ".." }
+rand = "0.5.4"
+env_logger = "0.5"

harness/src/interface.rs

@@ -0,0 +1,115 @@
+// Copyright 2018 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 2015 CoreOS, 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use raft::{eraftpb::Message, storage::MemStorage, Progress, ProgressSet, Raft, Result};
+use std::ops::{Deref, DerefMut};
+
+/// A simulated Raft façade for testing.
+///
+/// If the contained value is a `Some` operations happen. If they are a `None` operations are
+/// a no-op.
+///
+// Compare to upstream, we use struct instead of trait here.
+// Because to be able to cast Interface later, we have to make
+// Raft derive Any, which will require a lot of dependencies to derive Any.
+// That's not worthy for just testing purpose.
+pub struct Interface {
+    /// The raft peer.
+    pub raft: Option<Raft<MemStorage>>,
+}
+
+impl Interface {
+    /// Create a new interface to a new raft.
+    pub fn new(r: Raft<MemStorage>) -> Interface {
+        Interface { raft: Some(r) }
+    }
+
+    /// Step the raft, if it exists.
+    pub fn step(&mut self, m: Message) -> Result<()> {
+        match self.raft {
+            Some(_) => Raft::step(self, m),
+            None => Ok(()),
+        }
+    }
+
+    /// Read messages out of the raft.
+    pub fn read_messages(&mut self) -> Vec<Message> {
+        match self.raft {
+            Some(_) => self.msgs.drain(..).collect(),
+            None => vec![],
+        }
+    }
+
+    /// Initialize a raft with the given ID and peer set.
+    pub fn initial(&mut self, id: u64, ids: &[u64]) {
+        if self.raft.is_some() {
+            self.id = id;
+            let prs = self.take_prs();
+            self.set_prs(ProgressSet::with_capacity(
+                ids.len(),
+                prs.learner_ids().len(),
+            ));
+            for id in ids {
+                let progress = Progress::new(0, 256);
+                if prs.learner_ids().contains(id) {
+                    if let Err(e) = self.mut_prs().insert_learner(*id, progress) {
+                        panic!("{}", e);
+                    }
+                } else if let Err(e) = self.mut_prs().insert_voter(*id, progress) {
+                    panic!("{}", e);
+                }
+            }
+            let term = self.term;
+            self.reset(term);
+        }
+    }
+}
+
+impl From<Option<Raft<MemStorage>>> for Interface {
+    fn from(raft: Option<Raft<MemStorage>>) -> Self {
+        Self { raft }
+    }
+}
+
+impl From<Raft<MemStorage>> for Interface {
+    fn from(raft: Raft<MemStorage>) -> Self {
+        Self { raft: Some(raft) }
+    }
+}
+
+impl Deref for Interface {
+    type Target = Raft<MemStorage>;
+    fn deref(&self) -> &Raft<MemStorage> {
+        self.raft.as_ref().unwrap()
+    }
+}
+
+impl DerefMut for Interface {
+    fn deref_mut(&mut self) -> &mut Raft<MemStorage> {
+        self.raft.as_mut().unwrap()
+    }
+}

harness/src/lib.rs

@@ -0,0 +1,49 @@
+// Copyright 2018 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 2015 The etcd Authors
+//
+// 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*!
+
+This module contains various testing harness utilities for Raft.
+
+> If you want to build Raft without this, disable the `harness` feature.
+
+*/
+
+extern crate env_logger;
+extern crate raft;
+extern crate rand;
+
+mod interface;
+mod network;
+
+pub use self::{interface::Interface, network::Network};
+
+/// Do any common test initialization. Eg set up logging.
+#[doc(hidden)]
+pub fn setup_for_test() {
+    let _ = env_logger::try_init();
+}