| #region Copyright notice and license |
| |
| // Copyright 2015 gRPC 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. |
| |
| #endregion |
| |
| using System; |
| using Grpc.Core.Utils; |
| |
| namespace Grpc.Core |
| { |
| /// <summary> |
| /// Encapsulates the logic for serializing and deserializing messages. |
| /// </summary> |
| public class Marshaller<T> |
| { |
| readonly Func<T, byte[]> serializer; |
| readonly Func<byte[], T> deserializer; |
| |
| readonly Action<T, SerializationContext> contextualSerializer; |
| readonly Func<DeserializationContext, T> contextualDeserializer; |
| |
| /// <summary> |
| /// Initializes a new marshaller from simple serialize/deserialize functions. |
| /// </summary> |
| /// <param name="serializer">Function that will be used to serialize messages.</param> |
| /// <param name="deserializer">Function that will be used to deserialize messages.</param> |
| public Marshaller(Func<T, byte[]> serializer, Func<byte[], T> deserializer) |
| { |
| this.serializer = GrpcPreconditions.CheckNotNull(serializer, nameof(serializer)); |
| this.deserializer = GrpcPreconditions.CheckNotNull(deserializer, nameof(deserializer)); |
| // contextual serialization/deserialization is emulated to make the marshaller |
| // usable with the grpc library (required for backward compatibility). |
| this.contextualSerializer = EmulateContextualSerializer; |
| this.contextualDeserializer = EmulateContextualDeserializer; |
| } |
| |
| /// <summary> |
| /// Initializes a new marshaller from serialize/deserialize fuctions that can access serialization and deserialization |
| /// context. Compared to the simple serializer/deserializer functions, using the contextual version provides more |
| /// flexibility and can lead to increased efficiency (and better performance). |
| /// Note: This constructor is part of an experimental API that can change or be removed without any prior notice. |
| /// </summary> |
| /// <param name="serializer">Function that will be used to serialize messages.</param> |
| /// <param name="deserializer">Function that will be used to deserialize messages.</param> |
| public Marshaller(Action<T, SerializationContext> serializer, Func<DeserializationContext, T> deserializer) |
| { |
| this.contextualSerializer = GrpcPreconditions.CheckNotNull(serializer, nameof(serializer)); |
| this.contextualDeserializer = GrpcPreconditions.CheckNotNull(deserializer, nameof(deserializer)); |
| // gRPC only uses contextual serializer/deserializer internally, so emulating the legacy |
| // (de)serializer is not necessary. |
| this.serializer = (msg) => { throw new NotImplementedException(); }; |
| this.deserializer = (payload) => { throw new NotImplementedException(); }; |
| } |
| |
| /// <summary> |
| /// Gets the serializer function. |
| /// </summary> |
| public Func<T, byte[]> Serializer => this.serializer; |
| |
| /// <summary> |
| /// Gets the deserializer function. |
| /// </summary> |
| public Func<byte[], T> Deserializer => this.deserializer; |
| |
| /// <summary> |
| /// Gets the serializer function. |
| /// Note: experimental API that can change or be removed without any prior notice. |
| /// </summary> |
| public Action<T, SerializationContext> ContextualSerializer => this.contextualSerializer; |
| |
| /// <summary> |
| /// Gets the serializer function. |
| /// Note: experimental API that can change or be removed without any prior notice. |
| /// </summary> |
| public Func<DeserializationContext, T> ContextualDeserializer => this.contextualDeserializer; |
| |
| // for backward compatibility, emulate the contextual serializer using the simple one |
| private void EmulateContextualSerializer(T message, SerializationContext context) |
| { |
| var payload = this.serializer(message); |
| context.Complete(payload); |
| } |
| |
| // for backward compatibility, emulate the contextual deserializer using the simple one |
| private T EmulateContextualDeserializer(DeserializationContext context) |
| { |
| return this.deserializer(context.PayloadAsNewBuffer()); |
| } |
| } |
| |
| /// <summary> |
| /// Utilities for creating marshallers. |
| /// </summary> |
| public static class Marshallers |
| { |
| /// <summary> |
| /// Creates a marshaller from specified serializer and deserializer. |
| /// </summary> |
| public static Marshaller<T> Create<T>(Func<T, byte[]> serializer, Func<byte[], T> deserializer) |
| { |
| return new Marshaller<T>(serializer, deserializer); |
| } |
| |
| /// <summary> |
| /// Creates a marshaller from specified contextual serializer and deserializer. |
| /// Note: This method is part of an experimental API that can change or be removed without any prior notice. |
| /// </summary> |
| public static Marshaller<T> Create<T>(Action<T, SerializationContext> serializer, Func<DeserializationContext, T> deserializer) |
| { |
| return new Marshaller<T>(serializer, deserializer); |
| } |
| |
| /// <summary> |
| /// Returns a marshaller for <c>string</c> type. This is useful for testing. |
| /// </summary> |
| public static Marshaller<string> StringMarshaller |
| { |
| get |
| { |
| return new Marshaller<string>(System.Text.Encoding.UTF8.GetBytes, |
| System.Text.Encoding.UTF8.GetString); |
| } |
| } |
| } |
| } |