ABP微服务系列学习-搭建自己的微服务结构（四）

梦里梦外; 2023-09-24 21:28 51阅读 0赞

上篇我们实现了认证服务和网关服务，基本我们的基础服务已经完成了，接下来我们才需要做服务的数据迁移。  
这里我们需要使用EF的CodeFirst模式。通过DotnetCli的命令去操作：

dotnet ef migrations add init

### 修改项目[\#][Link 1] ###

编辑我们每个服务的EfCore项目的项目文件，添加Microsoft.EntityFrameworkCore.Tools的依赖，也可以通过VS的nuget包管理器安装。只有添加了这个依赖，我们才能使用dotnet ef命令。  
在项目文件中添加如下内容：

<ItemGroup>
      <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="7.0.1">
        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
      </PackageReference>
    </ItemGroup>

只添加这个依赖还不行，若直接运行dotnet ef命令的话，会提示我们需要实现一个DbContextFactory类。  
所以我们在每个服务的EFCore项目中都添加一个DbContextFactory类，类结构如下，每个服务对应修改一下名字即可

using System.IO;
    using JetBrains.Annotations;
    using Microsoft.EntityFrameworkCore;
    using Microsoft.EntityFrameworkCore.Design;
    using Microsoft.Extensions.Configuration;
    using Volo.Abp;
    
    
    namespace FunShow.AdministrationService.EntityFrameworkCore.EntityFrameworkCore
    {
        /* This class is needed for EF Core console commands
        * (like Add-Migration and Update-Database commands)
        * */
        public class AdministrationServiceDbContextFactory : IDesignTimeDbContextFactory<AdministrationServiceDbContext>
        {        
        	private readonly string _connectionString;
        
        	/* This constructor is used when you use EF Core tooling (e.g. Update-Database) */
            public AdministrationServiceDbContextFactory()
            {
            	_connectionString = GetConnectionStringFromConfiguration();
            }
            
            /* This constructor is used by DbMigrator application */
            public AdministrationServiceDbContextFactory([NotNull] string connectionString)
            {
                Check.NotNullOrWhiteSpace(connectionString, nameof(connectionString));
                _connectionString = connectionString;
            }
            public AdministrationServiceDbContext CreateDbContext(string[] args)
            {
            	AdministrationServiceEfCoreEntityExtensionMappings.Configure();
            
            var builder = new DbContextOptionsBuilder<AdministrationServiceDbContext>()
                .UseNpgsql(_connectionString, b =>
                {
                	b.MigrationsHistoryTable("__AdministrationService_Migrations");
                });
            
            	return new AdministrationServiceDbContext(builder.Options);
            }
            
            private static string GetConnectionStringFromConfiguration()
            {
                return BuildConfiguration()
                	.GetConnectionString(AdministrationServiceDbProperties.ConnectionStringName);
            }
            
            private static IConfigurationRoot BuildConfiguration()
            {
                var builder = new ConfigurationBuilder()
                    .SetBasePath(
                    Path.Combine(
                    Directory.GetCurrentDirectory(),
                    $"..{Path.Direct

[Link 1]: https://www.cnblogs.com/fanshaoO/p/17168561.html#%E4%BF%AE%E6%94%B9%E9%A1%B9%E7%9B%AE