1 /* 2 * Copyright 2024 Google Inc. All rights reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 import Foundation 18 19 /// FlatBufferGRPCMessage protocol that should allow us to invoke 20 /// initializers directly from the GRPC generated code 21 public protocol FlatBufferGRPCMessage { 22 23 /// Raw pointer which would be pointing to the beginning of the readable bytes 24 var rawPointer: UnsafeMutableRawPointer { get } 25 26 /// Size of readable bytes in the buffer 27 var size: Int { get } 28 29 init(byteBuffer: ByteBuffer) 30 } 31 32 /// Message is a wrapper around Buffers to to able to send Flatbuffers `Buffers` through the 33 /// GRPC library 34 public struct Message<T: FlatBufferObject>: FlatBufferGRPCMessage { 35 internal var buffer: ByteBuffer 36 37 /// Returns the an object of type T that would be read from the buffer 38 public var object: T { 39 T.init( 40 buffer, 41 o: Int32(buffer.read(def: UOffset.self, position: buffer.reader)) + 42 Int32(buffer.reader)) 43 } 44 45 public var rawPointer: UnsafeMutableRawPointer { 46 buffer.memory.advanced(by: buffer.reader) } 47 48 public var size: Int { Int(buffer.size) } 49 50 /// Initializes the message with the type Flatbuffer.Bytebuffer that is transmitted over 51 /// GRPC 52 /// - Parameter byteBuffer: Flatbuffer ByteBuffer object 53 public init(byteBuffer: ByteBuffer) { 54 buffer = byteBuffer 55 } 56 57 /// Initializes the message by copying the buffer to the message to be sent. 58 /// from the builder 59 /// - Parameter builder: FlatbufferBuilder that has the bytes created in 60 /// - Note: Use `builder.finish(offset)` before passing the builder without prefixing anything to it 61 public init(builder: inout FlatBufferBuilder) { 62 buffer = builder.sizedBuffer 63 builder.clear() 64 } 65 } 66