/*
* Copyright 2023 Google Inc. All rights reserved.
*
* 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.
*/
#if !os(WASI)
import Foundation
#else
import SwiftOverlayShims
#endif
/// FlatBufferGRPCMessage protocol that should allow us to invoke
/// initializers directly from the GRPC generated code
public protocol FlatBufferGRPCMessage {
/// Raw pointer which would be pointing to the beginning of the readable bytes
var rawPointer: UnsafeMutableRawPointer { get }
/// Size of readable bytes in the buffer
var size: Int { get }
init(byteBuffer: ByteBuffer)
}
/// Message is a wrapper around Buffers to to able to send Flatbuffers `Buffers` through the
/// GRPC library
public struct Message<T: FlatBufferObject>: FlatBufferGRPCMessage {
internal var buffer: ByteBuffer
/// Returns the an object of type T that would be read from the buffer
public var object: T {
T.init(
buffer,
o: Int32(buffer.read(def: UOffset.self, position: buffer.reader)) +
Int32(buffer.reader))
}
public var rawPointer: UnsafeMutableRawPointer {
buffer.memory.advanced(by: buffer.reader) }
public var size: Int { Int(buffer.size) }
/// Initializes the message with the type Flatbuffer.Bytebuffer that is transmitted over
/// GRPC
/// - Parameter byteBuffer: Flatbuffer ByteBuffer object
public init(byteBuffer: ByteBuffer) {
buffer = byteBuffer
}
/// Initializes the message by copying the buffer to the message to be sent.
/// from the builder
/// - Parameter builder: FlatbufferBuilder that has the bytes created in
/// - Note: Use `builder.finish(offset)` before passing the builder without prefixing anything to it
public init(builder: inout FlatBufferBuilder) {
buffer = builder.sizedBuffer
builder.clear()
}
}