实现 trait 后，您可以创建服务器，注册您的设备，并开始监听

use ascom_alpaca::Server;
use ascom_alpaca::api::CargoServerInfo;
use std::convert::Infallible;

// ...implement MyCamera...

#[tokio::main]
async fn main() -> eyre::Result<Infallible> {
    let mut server = Server {
        // helper macro to populate server information from your own Cargo.toml
        info: CargoServerInfo!(),
        ..Default::default()
    };

    // By default, the server will listen on dual-stack (IPv4 + IPv6) unspecified address with a randomly assigned port.
    // You can change that by modifying the `listen_addr` field:
    server.listen_addr.set_port(8000);

    // Create and register your device(s).
    server.devices.register(MyCamera { /* ... */ });

    // Start the infinite server loop.
    server.start().await
}

这将启动主 Alpaca 服务器以及自动发现响应器。

示例

• examples/camera-server.rs：一个跨平台示例，将您的连接的摄像头作为 Alpaca Camera公开。

  > env RUST_LOG=debug { cargo run --example camera-server --release }
        Finished release [optimized] target(s) in 0.60s
         Running `target\release\examples\camera-server.exe`
    2023-05-27T15:21:43.336191Z DEBUG camera_server: Registering webcam webcam=Webcam { unique_id: "150ddacb-7ad9-4754-b289-ae56210693e8::0", name: "Integrated Camera", description: "MediaFoundation Camera", max_format: CameraFormat { resolution: Resolution { width_x: 1280, height_y: 720 }, format: MJPEG, frame_rate: 30 }, subframe: RwLock { data: Subframe { bin: Size { x: 1, y: 1 }, offset: Point { x: 0, y: 0 }, size: Size { x: 1280, y: 720 } } }, last_exposure_start_time: RwLock { data: None }, last_exposure_duration: RwLock { data: None }, valid_bins: [1, 2, 4] }
    2023-05-27T15:21:43.339433Z DEBUG ascom_alpaca::server: Binding Alpaca server addr=[::]:8000
    2023-05-27T15:21:43.342897Z  INFO ascom_alpaca::server: Bound Alpaca server bound_addr=[::]:8000
    2023-05-27T15:21:43.369040Z  WARN join_multicast_groups{listen_addr=::}: ascom_alpaca::server::discovery: err=An unknown,
    invalid, or unsupported option or level was specified in a getsockopt or setsockopt call. (os error 10042)
    2023-05-27T15:21:43.370932Z DEBUG join_multicast_groups{listen_addr=::}: ascom_alpaca::server::discovery: return=()
    2023-05-27T15:21:43.371861Z DEBUG ascom_alpaca::server: Bound Alpaca discovery server
  

  通过将摄像头切换到其他支持的分辨率（与原始分辨率成比例）来实现合并。

  长时间曝光是通过累积单个帧直到总持续时间来模拟的。这种方法不能提供精确请求的曝光，但在其他方面工作得足够好。

• star-adventurer-alpaca：这是jsorrell/star-adventurer-alpaca的一个分支，它实现了通过串行端口为Star Adventurer支架的Alpaca API。原始项目功能相当丰富，并手动实现了Alpaca API，因此它是一个将代码移植到这个库的好测试案例。

从客户端访问设备

如果您知道要访问的设备服务器的地址，您可以直接通过Client结构体访问它。

use ascom_alpaca::Client;

let client = Client::new("https://127.0.0.1:8000")?;

// `get_server_info` returns high-level metadata of the server.
println!("Server info: {:#?}", client.get_server_info().await?);

// `get_devices` returns an iterator over all the devices registered on the server.
// Each is represented as a `TypedDevice` tagged enum encompassing all the device types as corresponding trait objects.
// You can either match on them to select the devices you're interested in, or, say, just print all of them:
println!("Devices: {:#?}", client.get_devices().await?.collect::<Vec<_>>());

如果您想在本地网络中发现设备服务器，可以通过discovery::DiscoveryClient结构体来这样做。

use ascom_alpaca::discovery::DiscoveryClient;
use ascom_alpaca::Client;
use futures::prelude::*;

// This holds configuration for the discovery client.
// You can customize prior to binding if you want.
let discovery_client = DiscoveryClient::new();
// This results in a discovery client bound to a local socket.
// It's intentionally split out into a separate API step to encourage reuse,
// for example so that user could click "Refresh devices" button in the UI
// and the application wouldn't have to re-bind the socket every time.
let mut bound_client = discovery_client.bind().await?;
// Now you can discover devices on the local networks.
bound_client.discover_addrs()
    // create a `Client` for each discovered address
    .map(|addr| Ok(Client::new_from_addr(addr)))
    .try_for_each(|client| async move {
        /* ...do something with devices via each client... */
        Ok::<_, eyre::Error>(())
    })
    .await?;

或者，如果您只想列出所有可用的设备，而不关心每个服务器的信息或错误

bound_client.discover_devices()
    .for_each(|device| async move {
        /* ...do something with each device... */
    })
    .await;

请注意，发现是一个基于UDP的协议，因此不能保证可靠性。

此外，如果设备服务器在多个网络接口上可用，则可能会多次发现相同的设备。虽然无法可靠地删除重复的服务器，但可以通过将它们存储在类似HashSet的东西或用于在服务器上注册任意设备的同一Devices结构体中来删除重复的设备。

use ascom_alpaca::api::{Camera, Devices};
use ascom_alpaca::discovery::DiscoveryClient;
use ascom_alpaca::Client;
use futures::prelude::*;

let devices =
    DiscoveryClient::new()
    .bind()
    .await?
    .discover_devices()
    .collect::<Devices>()
    .await;

// Now you can iterate over all the discovered devices via `iter_all`:
for (typed_device, index_within_category) in devices.iter_all() {
    println!("Discovered device: {typed_device:#?} (index: {index_within_category})");
}

// ...or over devices in a specific category via `iter<dyn Trait>`:
for camera in devices.iter::<dyn Camera>() {
    println!("Discovered camera: {camera:#?}");
}

示例

• examples/discover.rs：一个简单的发现示例，列出所有找到的服务器和设备。

• examples/camera-client.rs：一个跨平台的GUI示例，显示了从发现的Alpaca相机来的实时预览流。

  支持彩色、单色和Bayer传感器，并具有自动颜色转换的预览。

  

日志和跟踪

此crate使用tracing框架来记录跨度的事件，与Alpaca的ClientID、ClientTransactionID和ServerTransactionID字段集成。

您可以通过使用任何订阅crates来在您的应用程序中启用日志记录。

例如，tracing_subscriber::fmt将根据RUST_LOG环境变量将所有事件记录到stderr。

tracing_subscriber::fmt::init();

测试

由于这是一个用于与网络设备通信的库，因此应在较高层面上针对真实设备进行测试。

特别是，如果您正在实现Alpaca设备，请确保针对您的设备服务器运行ConformU - ASCOM的官方合规性检查器。

许可证

许可权属于以下任一

• Apache License，版本2.0 (LICENSE-APACHE-2.0)
• MIT许可证 (LICENSE-MIT)