Tingle.Extensions.MongoDB 4.9.0

Tingle.Extensions.MongoDB

[!IMPORTANT] The use of MongoDbContext will likely be replaced by EntityFrameworkCore support for MongoDB here.

MongoDB is a cross-platform NoSQL database program which uses JSON like documents with schema.

To connect to the database, we use the MongoClient class to access a MongoDB instance and through it, we can select the database we want to use. With the MongoClient instance we can drop a database, get a database, or retrieve names of the database from the server. There is no option for creating the database because once you pick/select a database and insert data into it, it automatically creates the database if it did not exist before.

MongoClient has a constructor which can accept a connection string or URL as parameters. If the database name is specified in the connection string, a singleton is added to the services. If the database name is specified in the MongoClient constructor parameters, it overrides any database name specified in the connection string.

This library provides extensions for working with MongoDB. It includes extension methods for IServiceCollection and for performing health checks on MongoDB.

Adding to services collection

If a MongoDB client is created that takes a connection string as a parameter, the GetConnectionString() function is called which returns the connection string to the MongoDB.

Also, a MongoDB database contains a collection to store data, To get a reference of the collection, it is required to call the GetCollection() function of the MongoDB database. The GetCollection() function takes a collection name as a parameter and returns a reference to the collection.

Health checks that monitor the performance and functioning of MongoDB are also added to the services as well.

In Program.cs add MongoDB services as shown in the code snippet below:

builder.Services.AddMongoDbContext<MyDbContext>(options => options.UseConnectionString(Configuration.GetConnectionString("Mongo")));

Configuration

If MongoDB client is configured with a connection string, add the ConnectionStrings configuration to the configuration file such as appsettings.json as in the example below:

{
    "ConnectionStrings:Mongo":"#{ConnectionStringsMongo}#"
}

Serializers

Diagnostics

Events for Mongo are produced on an ActivitySource named MongoDB. This is done by registering and instance of IEventSubscriber named MongoDbDiagnosticEvents to the ClusterConfigurator. However, this is done automatically when using MongoDbContext.

HealthChecks

services.AddHealthChecks()
        .AddMongoDbContextCheck<MyContext>();

Database setup

For development and preview environments, databases may need to be created automatically on startup. This can be done using the MONGO_CREATE_DATABASE environment variable.

{
  "profiles": {
    "SerilogSample": {
      "commandName": "Project",
      "dotnetRunMessages": true,
      "environmentVariables": {
        "DOTNET_ENVIRONMENT": "Development",
        "MONGO_CREATE_DATABASE": "true"
      }
    }
  }
}

In the application setup:

builder.Services.AddMongoDatabaseSetup<MyContext>(); // remember to override EnsureCreatedAsync(...) as per sample

Extensions

A number of extensions for building indexes or performing operations on collections exist.

See extensions for building ascending/descending indexes here

See extensions for bulk operations here