Azure Functions，如何拥有多个 .json 配置文件

Question

所以我编写了一个在本地运行良好的 azure 函数。我相信这取决于 local.setting.json 文件。但是当我将它发布到 azure 时，该功能不起作用，因为它找不到我定义的设置值。来自 Web 应用程序和控制台驱动的方法，我们将拥有与每个环境关联的不同配置文件。我怎样才能让它工作，这样我就可以拥有多个 settings.json 文件，例如一个用于 dev、stag 和 prod 环境？最终结果是使用 octopus deploy 进行部署，但此时，如果我什至无法使用 publish 进行部署，那么就没有机会这样做了。

我很困惑为什么这些信息不容易获得，因为假设这是一件很常见的事情？

Answer 1

此文档有 description 关于 local.settings.json:

By default, these settings are not migrated automatically when the project is published to Azure.

一种方法是使用 --publish-local-settings:

Publish settings in local.settings.json to Azure, prompting to overwrite if the setting already exists.

另一种方法是使用Manage Application Settings，Remote是Azure函数应用程序中的当前设置。或者选择添加设置以创建新的应用程序设置。详情可以参考这个文档：Function app settings.

Answer 2

我希望看到功能以与 asp.net 核心或控制台应用程序相同的方式支持环境特定设置。与此同时，我正在使用下面的代码，这有点老套（见评论）。

public class Startup : FunctionsStartup
{
    public override void Configure(IFunctionsHostBuilder builder)
    {
        // Get the path to the folder that has appsettings.json and other files.
        // Note that there is a better way to get this path: ExecutionContext.FunctionAppDirectory when running inside a function. But we don't have access to the ExecutionContext here.
        // Functions team should improve this in future. It will hopefully expose FunctionAppDirectory through some other way or env variable.
        string basePath = IsDevelopmentEnvironment() ?
            Environment.GetEnvironmentVariable("AzureWebJobsScriptRoot") :
            $"{Environment.GetEnvironmentVariable("HOME")}\site\wwwroot";

        var config = new ConfigurationBuilder()
            .SetBasePath(basePath)
            .AddJsonFile("appsettings.json", optional: false, reloadOnChange: false)  // common settings go here.
            .AddJsonFile($"appsettings.{Environment.GetEnvironmentVariable("AZURE_FUNCTIONS_ENVIRONMENT")}.json", optional: false, reloadOnChange: false)  // environment specific settings go here
            .AddJsonFile("local.settings.json", optional: true, reloadOnChange: false)  // secrets go here. This file is excluded from source control.
            .AddEnvironmentVariables()
            .Build();

        builder.Services.AddSingleton<IConfiguration>(config);
    }

    public bool IsDevelopmentEnvironment()
    {
        return "Development".Equals(Environment.GetEnvironmentVariable("AZURE_FUNCTIONS_ENVIRONMENT"), StringComparison.OrdinalIgnoreCase);
    }
}

Answer 3

好的，我现在可以使用了:) 因为我们使用章鱼部署，所以我们不需要多个配置文件，所以我们只有一个 appsettings.Release.json 文件也根据正在部署的环境获取替换的值。

主要功能代码如下。

public static class Function
    {
        // Format in a CRON Expression e.g. {second} {minute} {hour} {day} {month} {day-of-week}
        // https://docs.microsoft.com/en-us/azure/azure-functions/functions-bindings-timer
        // [TimerTrigger("0 59 23 * * *") = 11:59pm
        [FunctionName("Function")]
        public static void Run([TimerTrigger("0 59 23 * * *")]TimerInfo myTimer, ILogger log)
        {

            // If running in debug then we dont want to load the appsettings.json file, this has its variables substituted in octopus
            // Running locally will use the local.settings.json file instead
#if DEBUG
            IConfiguration config = new ConfigurationBuilder()
                .AddJsonFile("local.settings.json", optional: true, reloadOnChange: true)
                .AddEnvironmentVariables()
                .Build();
#else
            IConfiguration config = Utils.GetSettingsFromReleaseFile();
#endif

            // Initialise dependency injections
            var serviceProvider = Bootstrap.ConfigureServices(log4Net, config);

            var retryCount = Convert.ToInt32(config["RetryCount"]);

            int count = 0;
            while (count < retryCount)
            {
                count++;
                try
                {
                    var business = serviceProvider.GetService<IBusiness>();
                    business.UpdateStatusAndLiability();
                    return;
                }
                catch (Exception e)
                {
                    // Log your error
                }
            }

        }

    }

Utils.cs 文件如下所示

public static class Utils
    {

        public static string LoadSettingsFromFile(string environmentName)
        {
            var executableLocation = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
            // We need to go back up one level as the appseetings.Release.json file is not put in the bin directory
            var actualPathToConfig = Path.Combine(executableLocation, $"..\appsettings.{environmentName}.json");
            using (StreamReader reader = new StreamReader(actualPathToConfig))
            {
                return reader.ReadToEnd();
            }
        }

        public static IConfiguration GetSettingsFromReleaseFile()
        {
            var json = Utils.LoadSettingsFromFile("Release");
            var memoryFileProvider = new InMemoryFileProvider(json);

            var config = new ConfigurationBuilder()
                .AddJsonFile(memoryFileProvider, "appsettings.json", false, false)
                .Build();
            return config;
        }

    }

appsettings.Release.json 设置为 Content 和 Copy Always visual studio。看起来像这样

{
  "RetryCount": "#{WagonStatusAndLiabilityRetryCount}",
  "RetryWaitInSeconds": "#{WagonStatusAndLiabilityRetryWaitInSeconds}",
  "DefaultConnection": "#{YourConnectionString}"
}

实际上，我相信您可以在那里已经有一个 appsettings.config 文件并跳过 appsettings.Release.json 文件，但这是有效的，您现在可以用它做任何您想做的事。

Azure Functions，如何拥有多个 .json 配置文件

Azure Functions, how to have multiple .json config files

c#

azure

azure-functions

asp.net-core-2.0