I have created an HTTP trigger-based .Net 6 Azure FunctionApp and trying to configure the database connection strings, other key values, and dependency injections for my service classes but, I don't know how to call my configure method of Startup.cs file from Program.cs main function. I am new to FunctionApp-based hosting.

I have tried with IHostBuilder like the following in the Program.cs file, but it says: "does not contain a definition for ConfigureWebHostDefaults" even used the namespace => using Microsoft.AspNetCore.Hosting;

public static void Main(string[] args)
{
 var host = new HostBuilder().ConfigureFunctionsWorkerDefaults()            
        .Build();


 host.Run();
}

public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
 .ConfigureWebHostDefaults(webBuilder =>
 {
   webBuilder.UseStartup<Startup>();
 });

My Startup.cs file,

[assembly: FunctionsStartup(typeof(Startup))]
namespace kpi
{
  public class Startup : FunctionsStartup
  {
    private static IConfiguration _configuration = null;        

    public override void Configure(IFunctionsHostBuilder builder)
    {
     var serviceProvider = builder.Services.BuildServiceProvider();
     _configuration = serviceProvider.GetRequiredService<IConfiguration>();
     var appSettingsSection = _configuration.GetSection("AppSetting");
     builder.Services.Configure<AppSetting>(appSettingsSection);
     var appSettings = appSettingsSection.Get<AppSetting>();
     RuntimeConfig.appsettings = appSettings;

     var ConnectionString = RuntimeConfig.appsettings.AppDBConnection;
     builder.Services.AddDbContext<ShardingDbContext>(options => 
     options.UseSqlServer(ConnectionString), ServiceLifetime.Transient);
    }
   }
 }

I have used the FunctionStartup assembly, I don't know where I did go wrong, Can anyone help me to configure my connection strings from Startup.cs file in .Net6 Function App project?

CodePudding user response：

You can refer below code to fix your issue. For more details, please read official doc.

Guide for running C# Azure Functions in an isolated process

1. Startup.cs file

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Azure.Functions.Extensions.DependencyInjection;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;

[assembly: FunctionsStartup(typeof(triggerFunc.Startup))]
namespace triggerFunc
{
    public class Startup : FunctionsStartup
    {
        private static IConfiguration _configuration = null;
        public override void ConfigureAppConfiguration(IFunctionsConfigurationBuilder builder)
        {
            var context = builder.GetContext();

            // optional: customize your configuration sources 
            // here, we add appsettings.json files 
            // Note that these files are not automatically copied on build or publish. 
            //builder.ConfigurationBuilder
            //    .AddJsonFile(Path.Combine(context.ApplicationRootPath, "appsettings.json"), optional: true, reloadOnChange: false)
            //    .AddJsonFile(Path.Combine(context.ApplicationRootPath, $"appsettings.{context.EnvironmentName}.json"), optional: true, reloadOnChange: false);
        }

        public override void Configure(IFunctionsHostBuilder builder)
        {
            // get the configuration from the builder
            //var configuration = builder.GetContext().Configuration;

            var serviceProvider = builder.Services.BuildServiceProvider();
            _configuration = serviceProvider.GetRequiredService<IConfiguration>();
            var appSettingsSection = _configuration.GetSection("AppSetting");
            builder.Services.Configure<AppSetting>(appSettingsSection);
            var appSettings = appSettingsSection.Get<AppSetting>();
            RuntimeConfig.appsettings = appSettings;

            var ConnectionString = RuntimeConfig.appsettings.AppDBConnection;
            builder.Services.AddDbContext<ShardingDbContext>(options =>
            options.UseSqlServer(ConnectionString), ServiceLifetime.Transient);
        }
    }
}

2. Program.cs file

using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Hosting;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace triggerFunc
{
    public class Program
    {
        public static async Task Main(string[] args)
        {
            var builder = Host
              .CreateDefaultBuilder(args)
              .ConfigureFunctionsWorkerDefaults()
              .ConfigureAppConfiguration((hostingContext, configBuilder) =>
              {
                   var env = hostingContext.HostingEnvironment;
                    ;
              })
              .ConfigureServices((appBuilder, services) =>
              {
                  var configuration = appBuilder.Configuration;
              });

            await builder.Build().RunAsync();
        }
    }
}

CodePudding user response：

I just did override the function ConfigureAppConfiguration as below

public override void ConfigureAppConfiguration(IFunctionsConfigurationBuilder builder)
{
        FunctionsHostBuilderContext context = builder.GetContext();

        builder.ConfigurationBuilder
            .AddJsonFile(Path.Combine(context.ApplicationRootPath, "local.settings.json"), optional: true, reloadOnChange: false)
            .AddJsonFile(Path.Combine(context.ApplicationRootPath, $"local.settings.{context.EnvironmentName}.json"), optional: true, reloadOnChange: false)
            .AddEnvironmentVariables();
}

It's working fine in my local without an isolated way or Program.cs file and I don't know whether this same code will work on a server or not.

My local.setings.json

{
 "IsEncrypted": false,
 "AppSettings": {
 "AppDBConnection": "xyz....."
}

My Startup.cs file below and I can access the AppSettings section from my json file

public class Startup : FunctionsStartup
{

    private static IConfiguration _configuration = null;
    
    public override void Configure(IFunctionsHostBuilder builder)
    {
        //var connectionString = Environment.GetEnvironmentVariable("ConnectionStrings:DBConnection");

        var serviceProvider = builder.Services.BuildServiceProvider();
        _configuration = serviceProvider.GetRequiredService<IConfiguration>();
        var appSettingsSection = _configuration.GetSection("AppSettings");
        builder.Services.Configure<AppSettings>(appSettingsSection);
        var appSettings = appSettingsSection.Get<AppSettings>();
        RuntimeConfig.appsettings = appSettings;

        var ConnectionString = RuntimeConfig.appsettings.AppDBConnection;
        builder.Services.AddDbContext<ShardingDbContext>(options => options.UseSqlServer(ConnectionString), ServiceLifetime.Transient);
        builder.Services.AddScoped<ITestService, TestService>();
    }

    public override void ConfigureAppConfiguration(IFunctionsConfigurationBuilder builder)
    {
        FunctionsHostBuilderContext context = builder.GetContext();

        builder.ConfigurationBuilder
            .AddJsonFile(Path.Combine(context.ApplicationRootPath, "local.settings.json"), optional: true, reloadOnChange: false)
            .AddJsonFile(Path.Combine(context.ApplicationRootPath, $"local.settings.{context.EnvironmentName}.json"), optional: true, reloadOnChange: false)
            .AddEnvironmentVariables();
    }
}