| #region Copyright notice and license |
| |
| // Copyright 2018 The 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; |
| |
| namespace Grpc.Core |
| { |
| /// <summary> |
| /// Provides access to the payload being deserialized when deserializing messages. |
| /// </summary> |
| public abstract class DeserializationContext |
| { |
| /// <summary> |
| /// Get the total length of the payload in bytes. |
| /// </summary> |
| public abstract int PayloadLength { get; } |
| |
| /// <summary> |
| /// Gets the entire payload as a newly allocated byte array. |
| /// Once the byte array is returned, the byte array becomes owned by the caller and won't be ever accessed or reused by gRPC again. |
| /// NOTE: Obtaining the buffer as a newly allocated byte array is the simplest way of accessing the payload, |
| /// but it can have important consequences in high-performance scenarios. |
| /// In particular, using this method usually requires copying of the entire buffer one extra time. |
| /// Also, allocating a new buffer each time can put excessive pressure on GC, especially if |
| /// the payload is more than 86700 bytes large (which means the newly allocated buffer will be placed in LOH, |
| /// and LOH object can only be garbage collected via a full ("stop the world") GC run). |
| /// NOTE: Deserializers are expected not to call this method (or other payload accessor methods) more than once per received message |
| /// (as there is no practical reason for doing so) and <c>DeserializationContext</c> implementations are free to assume so. |
| /// </summary> |
| /// <returns>byte array containing the entire payload.</returns> |
| public virtual byte[] PayloadAsNewBuffer() |
| { |
| throw new NotImplementedException(); |
| } |
| |
| /// <summary> |
| /// Gets the entire payload as a ReadOnlySequence. |
| /// The ReadOnlySequence is only valid for the duration of the deserializer routine and the caller must not access it after the deserializer returns. |
| /// Using the read only sequence is the most efficient way to access the message payload. Where possible it allows directly |
| /// accessing the received payload without needing to perform any buffer copying or buffer allocations. |
| /// NOTE: When using this method, it is recommended to use C# 7.2 compiler to make it more useful (using Span type directly from your code requires C# 7.2)." |
| /// NOTE: Deserializers are expected not to call this method (or other payload accessor methods) more than once per received message |
| /// (as there is no practical reason for doing so) and <c>DeserializationContext</c> implementations are free to assume so. |
| /// </summary> |
| /// <returns>read only sequence containing the entire payload.</returns> |
| public virtual System.Buffers.ReadOnlySequence<byte> PayloadAsReadOnlySequence() |
| { |
| throw new NotImplementedException(); |
| } |
| } |
| } |