MongoDB.md

MongoDB Integration

This document explains how to integrate MongoDB as a database provider to ABP based applications and how to configure it.

Installation

Volo.Abp.MongoDB is the main nuget package for the MongoDB integration. Install it to your project (for a layered application, to your data/infrastructure layer):

Install-Package Volo.Abp.MongoDB

Then add AbpMongoDbModule module dependency to your module:

using Volo.Abp.MongoDB;
using Volo.Abp.Modularity;

namespace MyCompany.MyProject
{
    [DependsOn(typeof(AbpMongoDbModule))]
    public class MyModule : AbpModule
    {
        //...
    }
}

Creating a Mongo Db Context

ABP introduces Mongo Db Context concept (which is similar to Entity Framework Core's DbContext) to make it easier to use collections and configure them. An example is shown below:

public class MyDbContext : AbpMongoDbContext
{
    public IMongoCollection<Question> Questions => Collection<Question>();

    public IMongoCollection<Category> Categories => Collection<Category>();

    protected override void CreateModel(IMongoModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Question>(b =>
        {
            b.CollectionName = "Questions";
        });
    }
}

• It's derived from AbpMongoDbContext class.
• Adds a public IMongoCollection<TEntity> property for each mongo collection. ABP uses these properties to create default repositories by default.
• Overriding CreateModel method allows to configure collections (like their collection name in the database).

Registering DbContext To Dependency Injection

Use AddAbpDbContext method in your module to register your DbContext class for dependency injection system.

using Microsoft.Extensions.DependencyInjection;
using Volo.Abp.MongoDB;
using Volo.Abp.Modularity;

namespace MyCompany.MyProject
{
    [DependsOn(typeof(AbpMongoDbModule))]
    public class MyModule : AbpModule
    {
        public override void ConfigureServices(IServiceCollection services)
        {
            services.AddMongoDbContext<MyDbContext>();

            //...
        }
    }
}

Add Default Repositories

ABP can automatically create repositories for the entities in your Db Context. Just use AddDefaultRepositories() option on registration:

services.AddMongoDbContext<MyDbContext>(options =>
{
    options.AddDefaultRepositories();
});

This will create a repository for each aggreate root entity (classes derived from AggregateRoot) by default. If you want to create repositories for other entities too, then set includeAllEntities to true:

services.AddMongoDbContext<MyDbContext>(options =>
{
    options.AddDefaultRepositories(includeAllEntities: true);
});

Then you can inject and use IRepository<TEntity> or IQueryableRepository<TEntity> in your services.