WebJobApp 中 EF 上下文的依赖注入

Question

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我坚持了 2 周。

我正在尝试创建我的第一个需要使用实体框架的 webjobapp。 我试图将我的上下文注入到应用程序的构建器中，但出现错误：
无法将参数“db”绑定到类型 ApplicationDbContext。 确保绑定支持参数类型web 上有几个示例，但 Azure WebJob 的版本似乎变化很快，我找不到适用于我正在使用的版本的示例。 这些是我正在使用的 package 版本： Webjobs 3.0 EF.NET Core 7.0 Targeting .NET 7.0

这是我的代码：

 class Program
{
    static async Task Main()
    {
        var builder = new HostBuilder();
        builder.ConfigureWebJobs(b =>
        {
            b.AddTimers();
            b.AddAzureStorageCoreServices();
        });
        builder.ConfigureLogging((context, b) =>
        {
            b.AddConsole();
        });
        builder.ConfigureAppConfiguration((hostContext, configApp) =>
         {
             configApp.SetBasePath(Directory.GetCurrentDirectory());
             configApp.AddEnvironmentVariables(prefix: "ASPNETCORE_");
             configApp.AddJsonFile($"appsettings.json", true);
             configApp.AddJsonFile($"appsettings.{hostContext.HostingEnvironment.EnvironmentName}.json", true);

         });
       
       builder.ConfigureServices(services => { services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer("My full connection string"));
            services.AddTransient<IEmailSender, EmailSender>();
                                              });
        var host = builder.Build();
        using (host)
        //{
            await host.RunAsync();
        }
    }
}

public class Functions

public static void Sendemails([TimerTrigger("0 0 20 * * SUN-THU")] TimerInfo timer,
         ILogger logger,  ApplicationDbContext db)

    {
   
  
        var mylist = db.Users.ToList();
    
    }
}

我尝试使用以下代码而不是上面的代码来配置服务。 在检查构建器时，我可以看到服务已添加到构建器中。 但是在调用 builder.Build() 之后检查主机，服务不会出现在主机容器中。

var serviceCollection = new ServiceCollection();
ConfigureServices(serviceCollection);
     .....

  builder.ConfigureServices((context, sc) =>  sc= serviceCollection);
        var host = builder.Build();
   
        using (host)
        {
            await host.RunAsync();
        } 
}
 .....

    private void ConfigureServices(IServiceCollection services)
{
   
    services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer(_configuration.GetConnectionString("DefaultConnection")))
           
        
    }

项目文件

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net7.0</TargetFramework>
<ImplicitUsings>enable</ImplicitUsings>
<Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <None Remove="appsettings.Development.json" />
    <None Remove="appsettings.json" />
  </ItemGroup>

  <ItemGroup>
    <Content Include="appsettings.Development.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
      <ExcludeFromSingleFile>true</ExcludeFromSingleFile>
      <CopyToPublishDirectory>PreserveNewest</CopyToPublishDirectory>
    </Content>
    <Content Include="appsettings.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
      <ExcludeFromSingleFile>true</ExcludeFromSingleFile>
      <CopyToPublishDirectory>PreserveNewest</CopyToPublishDirectory>
    </Content>
  </ItemGroup>

  <ItemGroup>
    <PackageReference 
Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="7.0.1" />
    <PackageReference Include="Microsoft.Azure.WebJobs" Version="3.0.33" />
    <PackageReference Include="Microsoft.Azure.WebJobs.Extensions" Version="4.0.1" />
    <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.OpenApi.Configuration.AppSettings" Version="1.5.0" />
    <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.SendGrid" Version="3.0.2" />
    <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.Storage" Version="5.0.1" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="7.0.1" />
    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="7.0.0" />
    <PackageReference Include="Microsoft.Extensions.Logging" Version="7.0.0" />
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="7.0.0" />
    <PackageReference Include="Microsoft.Extensions.Options.ConfigurationExtensions" Version="7.0.0" />
    <PackageReference Include="SendGrid" Version="9.28.1" />
  </ItemGroup>

</Project>

Answer 1

最初即使我也遇到了同样的错误。

在Program.cs中做了一些更改。

我的程序.cs：

using Microsoft.AspNetCore.Identity.UI.Services;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

class Program
{
    static async Task Main()
    {
        var builder = new HostBuilder()
            .ConfigureWebJobs(b =>
            {
                b.AddTimers();
                b.AddAzureStorageCoreServices();
            })
            .ConfigureLogging((context, b) =>
            {
                b.AddConsole();
            })
             .ConfigureAppConfiguration((hostContext, configApp) =>
             {
                 configApp.SetBasePath(Directory.GetCurrentDirectory());
                 configApp.AddEnvironmentVariables(prefix: "ASPNETCORE_");
                 configApp.AddJsonFile($"appsettings.json", true);
                 configApp.AddJsonFile($"appsettings.{hostContext.HostingEnvironment.EnvironmentName}.json", true);
             })

        .ConfigureServices(services =>
        {
            services.AddDbContext<ApplicationDbContext>(
        options => options.UseSqlServer("MyDefaultConnection"));
            services.AddTransient<ApplicationDbContext, ApplicationDbContext>();
        });


        var host = builder.Build();
        using (host)
        {
            await host.RunAsync();
        }
    }
}

如果您在本地运行，请交叉检查一次local.settings.json文件。

我的local.settings.json ：

{
  "IsEncrypted": false,
  "Values": {
    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
    "FUNCTIONS_WORKER_RUNTIME": "dotnet"
  }
}

我的appsettings.json ：

{
  "ConnectionStrings": {
    "AzureWebJobsStorage": "Storage Account Connection String"
  }
}

也看看SO Thread一次。

参考资料取自MSDoc 。

Answer 2

我从头开始做这些步骤。

---

1-

public class ApplicationDbContext: IdentityDbContext<User, Role, Guid>
{
    public ApplicationDbContext(DbContextOptions options)
       : base(options)
    {
       
    }
 
     
    }

---

2-在appsettings.json中添加

---

"ConnectionStrings": {
  "SqlServer": "Data Source=;Initial Catalog=SpaceManagment;User ID=sa;Password=654321;MultipleActiveResultSets=true;TrustServerCertificate=True;Connection Timeout = 60"
},

---

3-

---

在program.cs中添加

---

 builder.Services.AddDbContext<ApplicationDbContext>(options =>
        {
            options
                .UseSqlServer(settings.SqlServer);
            //Tips
            // .ConfigureWarnings(warning => warning.Throw(RelationalEventId.QueryClientEvaluationWarning));
        });