# EFMigrationResourceBuilderExtensions Methods - Package: [Aspire.Hosting.EntityFrameworkCore](/reference/api/csharp/aspire.hosting.entityframeworkcore.md) - Type: [EFMigrationResourceBuilderExtensions](/reference/api/csharp/aspire.hosting.entityframeworkcore/efmigrationresourcebuilderextensions.md) - Kind: `Methods` - Members: `7` Extension methods for configuring EF Core migration resources. ## PublishAsMigrationBundle(IResourceBuilder, string?, bool, bool, string?) - Name: `PublishAsMigrationBundle(IResourceBuilder, string?, bool, bool, string?)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L161-L184) Configures the EF migration resource to generate a migration bundle during publishing. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder PublishAsMigrationBundle( this IResourceBuilder builder, string? targetRuntime = null, bool selfContained = false, bool publishContainer = false, string? baseImage = null) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. - `targetRuntime` (`string?`) `optional` The target runtime identifier for the bundle (e.g., `linux-x64`, `win-x64`). If `null` and `publishContainer` is `true`, defaults to `linux-x64` to match the default Linux base container image used for the generated `Dockerfile`. If `null` and `publishContainer` is `false`, the bundle targets the runtime hosting `aspire publish`. - `selfContained` (`bool`) `optional` If `true`, creates a self-contained bundle that includes the .NET runtime. - `publishContainer` (`bool`) `optional` If `true`, the bundle is published as a container image that applies migrations at deploy time. The resource becomes a compute resource; each target environment deploys it the same way it deploys any other container (supplying connection strings from referenced `ApplicationModel.IResourceWithConnectionString` dependencies via the standard `WithReference` mechanism). - `baseImage` (`string?`) `optional` Overrides the base container image for the generated `Dockerfile`. When `null` (the default), the image is derived from the project's target framework -- for example, `mcr.microsoft.com/dotnet/runtime:10.0` for a `net10.0` framework-dependent bundle. Set this when the default is not suitable, e.g. for preview SDKs or custom base images. Only meaningful when `publishContainer` is `true`. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks During `aspire publish`, the bundle executable is written to the publish output directory under the `efmigrations` folder. When `publishContainer` is `true`, Aspire also generates a `Dockerfile` that packages the bundle into a container image; the container reads the connection string from a `ConnectionStrings__` environment variable injected automatically for a `ApplicationModel.IResourceWithConnectionString` that the migration resource references or waits on. The startup project (the project on which `AddEFMigrations` was invoked) and the migrations project (configured via [EFMigrationResourceBuilderExtensions.WithMigrationsProject(IResourceBuilder, string)](/reference/api/csharp/aspire.hosting.entityframeworkcore/efmigrationresourcebuilderextensions/methods.md#withmigrationsproject-iresourcebuilder-efmigrationresource-string) or [EFMigrationResourceBuilderExtensions.WithMigrationsProject(IResourceBuilder, string)](/reference/api/csharp/aspire.hosting.entityframeworkcore/efmigrationresourcebuilderextensions/methods.md#withmigrationsproject-iresourcebuilder-efmigrationresource-string), if different) must both list the target runtime in their `` MSBuild property. If `publishContainer` = `true`, by default this means adding at minimum `linux-x64` to both projects. ## ATS metadata ### ATS export - Available to Polyglot AppHosts through the Aspire Type System. ## PublishAsMigrationScript(IResourceBuilder, bool, bool) - Name: `PublishAsMigrationScript(IResourceBuilder, bool, bool)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L103-L106) Configures the EF migration resource to generate a migration script during publishing. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder PublishAsMigrationScript( this IResourceBuilder builder, bool idempotent = true, bool noTransactions = false) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. - `idempotent` (`bool`) `optional` If `true` (the default), generates an idempotent script with `IF NOT EXISTS` checks so it can be safely re-run against a database that has already had some or all of the migrations applied. - `noTransactions` (`bool`) `optional` If `true`, omits transaction statements from the script. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks During `aspire publish`, the generated SQL script is written to the publish output directory under the `efmigrations` folder. The script is included as a deployment artifact, but it is not executed automatically during deployment. ## ATS metadata ### ATS export - Available to Polyglot AppHosts through the Aspire Type System. ## RunDatabaseUpdateOnStart(IResourceBuilder) - Name: `RunDatabaseUpdateOnStart(IResourceBuilder)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L38-L46) Configures the EF migration resource to run database update when the AppHost starts. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder RunDatabaseUpdateOnStart( this IResourceBuilder builder) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks When enabled, migrations are applied during AppHost startup. This only affects local run-mode execution. The migrations resource is not deployed with the app, so this method has no effect during publish or deployment. A health check is automatically registered for this resource, allowing other resources to use `.WaitFor()` to wait until migrations complete before starting. ## ATS metadata ### ATS export - Available to Polyglot AppHosts through the Aspire Type System. ## WithMigrationNamespace(IResourceBuilder, string) - Name: `WithMigrationNamespace(IResourceBuilder, string)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L218-L220) Configures the namespace for new migrations created with the Add Migration command. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder WithMigrationNamespace( this IResourceBuilder builder, string @namespace) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. - `namespace` (`string`) The namespace for generated migrations. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks If not specified, the namespace will be derived from the project's default namespace. Example: `MyApp.Data.Migrations` or `MyApp.Infrastructure.Migrations`. ## ATS metadata ### ATS export - Available to Polyglot AppHosts through the Aspire Type System. ## WithMigrationOutputDirectory(IResourceBuilder, string) - Name: `WithMigrationOutputDirectory(IResourceBuilder, string)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L200-L202) Configures the output directory for new migrations created with the Add Migration command. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder WithMigrationOutputDirectory( this IResourceBuilder builder, string outputDirectory) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. - `outputDirectory` (`string`) The output directory path relative to the project root. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks If not specified, migrations will be placed in the default `Migrations` directory. Example: `Data/Migrations` or `Infrastructure/Migrations`. ## ATS metadata ### ATS export - Available to Polyglot AppHosts through the Aspire Type System. ## WithMigrationsProject(IResourceBuilder, string) - Name: `WithMigrationsProject(IResourceBuilder, string)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L240-L244) Configures a separate project containing the migrations using a project path. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder WithMigrationsProject( this IResourceBuilder builder, string projectPath) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. - `projectPath` (`string`) The path to the project file containing the migrations. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks Use this method when the migrations are in a different project than the startup project. The target project's path will be used for migration operations while the startup project remains the original project. The project resource on which AddEFMigrations is invoked should be the startup project (the project that contains the DbContext configuration). ## ATS metadata ### Ignored by ATS - Excluded from automatic Polyglot export. ## WithMigrationsProject(IResourceBuilder) - Name: `WithMigrationsProject(IResourceBuilder)` - Modifiers: `extension` - Returns: `IResourceBuilder` - Source: [GitHub](https://github.com/microsoft/aspire/blob/becb48e2d61099e35ae336d527d3875e928d6594/src/Aspire.Hosting.EntityFrameworkCore/EFMigrationResourceBuilderExtensions.cs#L265-L266) Configures a separate project containing the migrations using a project metadata type. ```csharp public static class EFMigrationResourceBuilderExtensions { public static IResourceBuilder WithMigrationsProject( this IResourceBuilder builder) { // ... } } ``` ## Parameters - `builder` (`IResourceBuilder`) The resource builder. ## Returns `IResourceBuilder` -- The resource builder for chaining. ## Remarks Use this method when the migrations are in a different project than the startup project. The target project's path will be used for migration operations while the startup project remains the original project. The project resource on which AddEFMigrations is invoked should be the startup project (the project that contains the DbContext configuration). ## ATS metadata ### Ignored by ATS - Excluded from automatic Polyglot export.