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docs/en/Community-Articles/2025-02-12-Migrate-DB-From-Your-Web-Project/Post.md

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+# Migrate Your DB from the Web Application — Adding a DB Migration Controller in ABP Framework 
+
+In some scenarios, you might prefer to **update your ABP project's database by simply visiting a URL** rather than running a console application (such as a typical `DbMigrator` project). This post demonstrates how to do that in an ABP application. In my sample application I used the single-layer project but you can benefit the same approach for other templates. My sample project name was created with this name: **Acme.BookStore**.
+
+------
+
+## Step 1: Remove the Existing Localization Middleware
+
+Open your web project's module class file—this is typically in `BookStoreModule.cs` if you’re using the no-layer template. 
+Or if your project is multi-layered, it's `BookStoreWebModule.cs`. Find the below line and **remove** it:
+
+```csharp
+app.UseAbpRequestLocalization();
+```
+
+The reason is that the localization middleware depends on the database, which does not yet exist! 
+We'll add this middleware conditionally in the next step.
+
+------
+
+## Step 2: Conditionally Use the Localization Middleware
+
+We only want `AbpRequestLocalizationMiddleware` for routes **other than** our new migration endpoint (`/api/migrate`). To achieve this, we use [Middleware Branching](https://learn.microsoft.com/en-us/aspnet/core/fundamentals/middleware/). Our new controller will work on `/api/migrate` endpoint, so let's add a condition for this specific URL.
+
+```csharp
+app.UseWhen(httpContext =>
+    !httpContext.Request.Path.StartsWithSegments("/api/migrate", StringComparison.OrdinalIgnoreCase),
+    appBuilder =>
+    {
+        appBuilder.UseAbpRequestLocalization();
+    }
+);
+```
+
+This ensures all requests except `/api/migrate` will still use `AbpRequestLocalization` middleware.
+
+------
+
+## Step 3: Create the Migration Controller
+
+Create a new file named `MigrationController.cs` under your `Controllers` folder or wherever you store controllers. 
+Then copy-paste the following class:
+
+```csharp
+using Microsoft.AspNetCore.Mvc;
+using Volo.Abp.AspNetCore.Mvc;
+using Volo.Abp.Data;
+using Volo.Abp.Identity;
+using Volo.Abp.MultiTenancy;
+using Volo.Saas.Tenants;
+
+namespace Acme.BookStore.Web.Controllers //TODO: you may need to fix this namespace!
+{
+    [Route("api")]
+    [IgnoreAntiforgeryToken]
+    public class MigrationController : AbpController
+    {
+        private const string DefaultAdminEmail = "admin@admin.com";
+        private const string DefaultAdminPassword = "My-Admin-Password";
+
+        private readonly IDataSeeder _dataSeeder;
+        private readonly ITenantRepository _tenantRepository;
+        private readonly ICurrentTenant _currentTenant;
+        private readonly IEnumerable<DbSchemaMigrator> _dbSchemaMigrators;
+
+        public MigrationController(
+            IDataSeeder dataSeeder,
+            ITenantRepository tenantRepository,
+            ICurrentTenant currentTenant,
+            IEnumerable<DbSchemaMigrator> dbSchemaMigrators)
+        {
+            _dataSeeder = dataSeeder;
+            _tenantRepository = tenantRepository;
+            _currentTenant = currentTenant;
+            _dbSchemaMigrators = dbSchemaMigrators;
+        }
+
+        [HttpGet]
+        [Route("migrate")]
+        public async Task<IActionResult> MigrateAsync(CancellationToken cancellationToken)
+        {
+            try
+            {
+                Logger.LogInformation("Started database migrations...");
+
+                await MigrateDatabaseSchemaAsync();
+                await SeedDataAsync();
+
+                Logger.LogInformation("Successfully completed host database migrations. Started migrating tenant databases...");
+
+                if (_currentTenant.IsAvailable) // or check MultiTenancyConsts.IsEnabled
+                {
+                    await MigrateTenantDatabases(cancellationToken);
+                }
+
+                Logger.LogInformation("Successfully completed all database migrations.");
+                return Ok("Migration and seed completed successfully.");
+            }
+            catch (Exception ex)
+            {
+                return BadRequest($"An error occurred during migration: {ex.Message}");
+            }
+        }
+
+        private async Task MigrateTenantDatabases(CancellationToken cancellationToken)
+        {
+            var tenants = await _tenantRepository.GetListAsync(includeDetails: true, cancellationToken: cancellationToken);
+
+            var migratedDatabaseSchemas = new HashSet<string>();
+            foreach (var tenant in tenants)
+            {
+                using (_currentTenant.Change(tenant.Id))
+                {
+                    if (tenant.ConnectionStrings.Any())
+                    {
+                        var tenantConnectionStrings = tenant.ConnectionStrings
+                            .Select(x => x.Value)
+                            .ToList();
+
+                        if (!migratedDatabaseSchemas.IsSupersetOf(tenantConnectionStrings))
+                        {
+                            await MigrateDatabaseSchemaAsync(tenant);
+                            migratedDatabaseSchemas.AddIfNotContains(tenantConnectionStrings);
+                        }
+                    }
+
+                    await SeedDataAsync(tenant);
+                }
+
+                Logger.LogInformation($"Successfully completed {tenant.Name} tenant database migrations.");
+            }
+        }
+
+        private async Task MigrateDatabaseSchemaAsync(Tenant tenant = null)
+        {
+            Logger.LogInformation($"Migrating schema for {(tenant == null ? "host" : tenant.Name + " tenant")} database...");
+            foreach (var migrator in _dbSchemaMigrators)
+            {
+                await migrator.MigrateAsync();
+            }
+        }
+
+        private async Task SeedDataAsync(Tenant tenant = null)
+        {
+            Logger.LogInformation($"Executing {(tenant == null ? "host" : tenant.Name + " tenant")} database seed...");
+
+            await _dataSeeder.SeedAsync(
+                new DataSeedContext(tenant?.Id)
+                    .WithProperty(IdentityDataSeedContributor.AdminEmailPropertyName, DefaultAdminEmail)
+                    .WithProperty(IdentityDataSeedContributor.AdminPasswordPropertyName, DefaultAdminPassword)
+            );
+        }
+    }
+}
+```
+
+
+
+------
+
+
+
+## Step 4: Navigate to the Migration URL
+
+Build and run your web application. Then visit:
+
+```
+https://your-website.com/api/migrate
+```
+
+If your database did not exist, it will be created, and the default data will be seeded. If you enabled multi-tenancy, the tenant databases will also be migrated in this solution.
+
+------
+
+
+
+**That’s all there is to it!** By adding a simple controller and selectively applying the localization middleware, you can migrate your ABP app’s database with a single URL.
+
+
+
+Happy coding 😊