使用.NetCore编写命令行工具(CLI)

[Route("api/items")]
[ApiController]
public class ItemsController : ControllerBase
{
    private readonly IMemoryCache _cache;
    private readonly string _key = "items";

    public ItemsController(IMemoryCache memoryCache)
    {
        _cache = memoryCache;
    }

    [HttpGet]
    public IActionResult List()
    {
        var items = _cache.Get>(_key);
        return Ok(items);
    }

    [HttpGet("{id}")]
    public IActionResult Get(string id)
    {
        var item = _cache.Get>(_key).FirstOrDefault(n => n.Id == id);
        return Ok(item);
    }

    [HttpPost]
    public IActionResult Create(ItemForm form)
    {
        var items = _cache.Get>(_key) ?? new List();

        var item = new Item
        {
            Id = Guid.NewGuid().ToString("N"),
            Name = form.Name,
            Age = form.Age
        };

        items.Add(item);

        _cache.Set(_key, items);
        
        return Ok(item);
    }

    [HttpDelete("{id}")]
    public IActionResult Delete(string id)
    {
        var items = _cache.Get>(_key);

        var item = items?.SingleOrDefault(n => n.Id == id);
        if (item == null)
        {
            return NotFound();
        }

        items.Remove(item);
        _cache.Set(_key, items);

        return Ok();
    }
}

[HelpOption(Inherited = true)] //显示指令帮助，并且让子指令也继承此设置
[Command(Description = "A tool to communicate with web api"), //指令描述
 Subcommand(typeof(ConfigCommand), typeof(ItemCommand))] //子指令
class Program
{
    public static int Main(string[] args)
    {
        //配置依赖注入
        var serviceCollection = new ServiceCollection();

        serviceCollection.AddSingleton(PhysicalConsole.Singleton);
        serviceCollection.AddSingleton();
        serviceCollection.AddHttpClient();

        var services = serviceCollection.BuildServiceProvider();

        var app = new CommandLineApplication();
        app.Conventions
            .UseDefaultConventions()
            .UseConstructorInjection(services);

        var cOnsole= (IConsole)services.GetService(typeof(IConsole));

        try
        {
            return app.Execute(args);
        }
        catch (UnrecognizedCommandParsingException ex) //处理未定义指令
        {
            console.WriteLine(ex.Message);
            return -1;
        }
    }

    //指令逻辑
    private int OnExecute(CommandLineApplication app, IConsole console)
    {
        console.WriteLine("Please specify a command.");
        app.ShowHelp();
        return 1;
    }
}

[Command("config", Description = "Manage config"),
 Subcommand(typeof(GetCommand), typeof(SetCommand))]
public class ConfigCommand
{
    private int OnExecute(CommandLineApplication app, IConsole console)
    {
        console.Error.WriteLine("Please submit a sub command.");
        app.ShowHelp();
        return 1;
    }
}

[Command("item", Description = "Manage item"),
 Subcommand(typeof(CreateCommand), typeof(GetCommand), typeof(ListCommand), typeof(DeleteCommand))]
public class ItemCommand
{
    private int OnExecute(CommandLineApplication app, IConsole console)
    {
        console.Error.WriteLine("Please submit a sub command.");
        app.ShowHelp();
        return 1;
    }
}

public interface IConfigService
{
    void Set();

    Config Get();
}

public class ConfigService: IConfigService
{
    private readonly IConsole _console;
    private readonly string _directoryName;
    private readonly string _fileName;

    public ConfigService(IConsole console)
    {
        _console = console;
        _directoryName = ".api-cli";
        _fileName = "config.json";
    }

    public void Set()
    {
        var directory = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), _directoryName);
        if (!Directory.Exists(directory))
        {
            Directory.CreateDirectory(directory);
        }

        var cOnfig= new Config
        {
            //弹出交互框，让用户输入，设置默认值为http://localhost:5000/
            Endpoint = Prompt.GetString("Specify the endpoint:", "http://localhost:5000/")
        };

        if (!config.Endpoint.EndsWith("/"))
        {
            config.Endpoint += "/";
        }

        var filePath = Path.Combine(directory, _fileName);

        using (var outputFile = new StreamWriter(filePath, false, Encoding.UTF8))
        {
            outputFile.WriteLine(JsonConvert.SerializeObject(config, Formatting.Indented));
        }
        _console.WriteLine($"Config saved in {filePath}.");
    }

    public Config Get()
    {
        var filePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), _directoryName, _fileName);

        if (File.Exists(filePath))
        {
            var cOntent= File.ReadAllText(filePath);
            try
            {
                var cOnfig= JsonConvert.DeserializeObject(content);
                return config;
            }
            catch
            {
                _console.WriteLine("The config is invalid, please use 'config set' command to reset one.");
            }
        }
        else
        {
            _console.WriteLine("Config is not existed, please use 'config set' command to set one.");
        }

        return null;
    }
}

public interface IItemClient
{
    Task<string> Create(ItemForm form);

    Task<string> Get(string id);

    Task<string> List();

    Task<string> Delete(string id);
}

public class ItemClient : IItemClient
{
    public HttpClient Client { get; }

    public ItemClient(HttpClient client, IConfigService configService)
    {
        var cOnfig= configService.Get();
        if (cOnfig== null)
        {
            return;
        }

        client.BaseAddress = new Uri(config.Endpoint);

        Client = client;
    }

    public async Task<string> Create(ItemForm form)
    {
        var cOntent= new StringContent(JsonConvert.SerializeObject(form), Encoding.UTF8, "application/json");
        var result = await Client.PostAsync("/api/items", content);

        if (result.IsSuccessStatusCode)
        {
            var stream = await result.Content.ReadAsStreamAsync();
            var item = Deserialize(stream);
            return $"Item created, info:{item}";
        }

        return "Error occur, please again later.";
    }

    public async Task<string> Get(string id)
    {
        var result = await Client.GetAsync($"/api/items/{id}");

        if (result.IsSuccessStatusCode)
        {
            var stream = await result.Content.ReadAsStreamAsync();
            var item = Deserialize(stream);

            var respOnse= new StringBuilder();
            response.AppendLine($"{"Id".PadRight(40, ' ')}{"Name".PadRight(20, ' ')}Age");
            response.AppendLine($"{item.Id.PadRight(40, ' ')}{item.Name.PadRight(20, ' ')}{item.Age}");
            return response.ToString();
        }

        return "Error occur, please again later.";
    }

    public async Task<string> List()
    {
        var result = await Client.GetAsync($"/api/items");

        if (result.IsSuccessStatusCode)
        {
            var stream = await result.Content.ReadAsStreamAsync();
            var items = Deserialize>(stream);

            var respOnse= new StringBuilder();
            response.AppendLine($"{"Id".PadRight(40, ' ')}{"Name".PadRight(20, ' ')}Age");

            if (items != null && items.Count > 0)
            {
                foreach (var item in items)
                {
                    response.AppendLine($"{item.Id.PadRight(40, ' ')}{item.Name.PadRight(20, ' ')}{item.Age}");
                }
            }
            
            return response.ToString();
        }

        return "Error occur, please again later.";
    }

    public async Task<string> Delete(string id)
    {
        var result = await Client.DeleteAsync($"/api/items/{id}");

        if (result.IsSuccessStatusCode)
        {
            return $"Item {id} deleted.";
        }

        if (result.StatusCode == HttpStatusCode.NotFound)
        {
            return $"Item {id} not found.";
        }

        return "Error occur, please again later.";
    }

    private static T Deserialize(Stream stream)
    {
        using var reader = new JsonTextReader(new StreamReader(stream));
        var serializer = new JsonSerializer();
        return (T)serializer.Deserialize(reader, typeof(T));
    }
}

　　
　　  Exe
　　  netcoreapp3.1
　　  api-cli
　　

　　cd src/NetCoreCLI

　　dotnet publish -c Release -r linux-x64 /p:PublishSingleFile=true

　　dotnet publish -c Release -r win-x64 /p:PublishSingleFile=true

    dotnet publish -c Release -r osx-x64 /p:PublishSingleFile=true

    sudo chmod +x api-cli #授权
    sudo mv ./api-cli /usr/local/bin/api-cli #移动到PATH