Hyperbee.Migrations.Providers.Couchbase 1.2.7

Hyperbee Migrations Couchbase Provider

Welcome to Hyperbee.Migrations.Providers.Couchbase, an extension to the foundational Hyperbee.Migrations library. This extension is specifically designed to incorporate support for Couchbase.

Introduction

The Hyperbee.Migrations.Providers.Couchbase library is an tool for developers seeking to perform database migrations in a Couchbase environment using the Hyperbee.Migrations library. This library furnishes a comprehensive suite of tools and functionalities that integrate effortlessly with Hyperbee.Migrations, thereby enabling developers to harness the robust capabilities of Couchbase in their applications.

The Hyperbee.Migrations.Providers.Couchbase library is equipped to assist developers in creating, updating, and managing their Couchbase databases. With the aid of this library, developers can concentrate their efforts on the development of their application, while the library handles the intricacies of database management.

We are committed to continuous improvement and feature enhancement. We appreciate your interest and look forward to your valuable feedback.

Please see Hyperbee Migrations' Read Me for non-database specific usage.

Configuration

Add Couchbase Services

// In Startup.cs
public void ConfigureServices(IServiceCollection services)
{
    // Configure MongoDB
    services.AddCouchbase();

    // Add the MigrationRunner
    services.AddCouchbaseMigrations(...);
}

public void Configure(IApplicationBuilder app, ...)
{
    // Run pending migrations.
    var migrationService = app.ApplicationServices.GetRequiredService<MigrationRunner>();
    migrationService.Run();
}

Preventing simultaneous migrations

By default, Hyperbee Migrations prevents parallel migration runner execution. If you have 2 instances of your app running, and both try to run migrations, Hyperbee Migrations will prevent the second instance from running migrations and will log a warning.

Hyperbee Migrations accomplishes this by using a distributed lock at the database layer. The default implementation is based on the provider and uses a timeout and an auto-renewal interval to prevent orphaned locks.

If you want to change this behavior you can override the default options:

services.AddCouchbaseMigrations( options =>
{
    // Locking is on by default. Set to false to allow simultaneous runners - but don't be that guy.
    options.LockingEnabled = false;

    // You can change locking behavior. Defaults shown.
    options.LockMaxLifetime = TimeSpan.FromHours( 1 );         // max time-to-live
    options.LockExpireInterval = TimeSpan.FromMinutes( 5 );    // expire heartbeat
    options.LockRenewInterval = TimeSpan.FromMinutes( 2 );     // renewal heartbeat
});

Dependency Injection

Hyperbee Migrations relies on dependency injection to pass services to your migration.

[Migration(1)]
public class MyMigration : Migration
{
	private IClusterProvider _clusterProvider;
    private ILogger _logger;

	// Injected services registered with the container
	public MyMigration( IClusterProvider clusterProvider, ILogger<MyMigration> logger )
	{
        _clusterProvider = clusterProvider;
		_logger = logger;
	}

	public async override Task UpAsync( CancellationToken cancellationToken = default )
	{
		// do something with clusterProvider
	}
}

The MongoDB provider also provides a MongoDBResourceRunner<MyMigration> that adds helpful functionality when using embedded resources.

• StatementsFromAsync run SQL++ (N1QL) statements for different bucket/scope/collections within Couchbase.
• DocumentsFromAsync Upserts documents into Couchbase. This is normally use for pre-seeding.

[Migration(1)]
public class MyMigration : Migration
{
    private readonly CouchbaseResourceRunner<MyMigration> _resourceRunner;

    public CreateInitialBuckets( CouchbaseResourceRunner<MyMigration> resourceRunner )
    {
        _resourceRunner = resourceRunner;
    }

    public override async Task UpAsync( CancellationToken cancellationToken = default )
    {
        // run a `resource` migration to create initial buckets and state.
        // resource migrations are atypical; prefer `n1ql` migrations.

        await _resourceRunner.StatementsFromAsync( new[]
            {
                "statements.json",
                "migrationbucket/statements.json"
            },
            cancellationToken
        );

        await _resourceRunner.DocumentsFromAsync( new[]
            {
                "migrationbucket/_default"
            },
            cancellationToken
        );
    }
}