[VOL-2235] Mocks and interfaces for rw-core

This update consists of mocks that are used by the rw-core
during unit testing.  It also includes interfaces used for unit
tests.

Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/go.etcd.io/etcd/etcdserver/api/v3lock/v3lockpb/v3lock.proto b/vendor/go.etcd.io/etcd/etcdserver/api/v3lock/v3lockpb/v3lock.proto
new file mode 100644
index 0000000..7220c7f
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/etcdserver/api/v3lock/v3lockpb/v3lock.proto
@@ -0,0 +1,65 @@
+syntax = "proto3";
+package v3lockpb;
+
+import "gogoproto/gogo.proto";
+import "etcd/etcdserver/etcdserverpb/rpc.proto";
+
+// for grpc-gateway
+import "google/api/annotations.proto";
+
+option (gogoproto.marshaler_all) = true;
+option (gogoproto.unmarshaler_all) = true;
+
+// The lock service exposes client-side locking facilities as a gRPC interface.
+service Lock {
+  // Lock acquires a distributed shared lock on a given named lock.
+  // On success, it will return a unique key that exists so long as the
+  // lock is held by the caller. This key can be used in conjunction with
+  // transactions to safely ensure updates to etcd only occur while holding
+  // lock ownership. The lock is held until Unlock is called on the key or the
+  // lease associate with the owner expires.
+  rpc Lock(LockRequest) returns (LockResponse) {
+      option (google.api.http) = {
+        post: "/v3/lock/lock"
+        body: "*"
+    };
+  }
+
+  // Unlock takes a key returned by Lock and releases the hold on lock. The
+  // next Lock caller waiting for the lock will then be woken up and given
+  // ownership of the lock.
+  rpc Unlock(UnlockRequest) returns (UnlockResponse) {
+      option (google.api.http) = {
+        post: "/v3/lock/unlock"
+        body: "*"
+    };
+  }
+}
+
+message LockRequest {
+  // name is the identifier for the distributed shared lock to be acquired.
+  bytes name = 1;
+  // lease is the ID of the lease that will be attached to ownership of the
+  // lock. If the lease expires or is revoked and currently holds the lock,
+  // the lock is automatically released. Calls to Lock with the same lease will
+  // be treated as a single acquisition; locking twice with the same lease is a
+  // no-op.
+  int64 lease = 2;
+}
+
+message LockResponse {
+  etcdserverpb.ResponseHeader header = 1;
+  // key is a key that will exist on etcd for the duration that the Lock caller
+  // owns the lock. Users should not modify this key or the lock may exhibit
+  // undefined behavior.
+  bytes key = 2;
+}
+
+message UnlockRequest {
+  // key is the lock ownership key granted by Lock.
+  bytes key = 1;
+}
+
+message UnlockResponse {
+  etcdserverpb.ResponseHeader header = 1;
+}