README.md

AzureGems Repository - Cosmos DB

CosmosDbContainerRepository<T> provides a Cosmos DB specific implementation of the AzureGems.Repository IRepository<T> interface.

The extension method AddCosmosContext<CosmosContext>() allows you to define a DbContext (just like EFCore) and have it added to the ServiceCollection and injected into your services.

Getting Started

Defining your CosmosContext is straight forward.

1. Create a new class that inherits from CosmosContext.
2. Declare a public IRepository<T> property for each model type (aka Domain Entity) with both get and set accessors.

public class LittleNorthwindCosmosContext : CosmosContext
{
    public IRepository<Customer> Customers { get; set; }
    public IRepository<Order> Orders { get; set; }
    public IRepository<Invoice> Invoices { get; set; }
}

NOTE: Each model type must inherit from BaseType to satisfy the generic constraints for IRepository<T>

3. Register your CosmosContext with the ServiceCollection which will take care of instantiating it and initializing all the repositories to be backed by the correct Cosmos DB containers.

In Startup.cs you should already have added Cosmos DB and specified your Container Configurations. See Adding AzureGems.CosmosDb

4. Register your CosmosContext using the AddCosmosContext() extension method:

services.AddCosmosDb(builder =>
{
	builder
		.WithContainerConfig(c =>
		{
			c.AddContainer<Vehicle>(containerId: "Cars", partitionKeyPath: "/brand", queryByDiscriminator: false, throughput: 20000);
			c.AddContainer<Receipt>(containerId: "Receipts", partitionKeyPath: "/id");
			c.AddContainer<Accessory>(containerId: "Accessories", partitionKeyPath: "/category");
		});
});

// Add your CosmosContext
services.AddCosmosContext<LittleNorthwindCosmosContext>();

Now your CosmosContext is ready to be injected and used by your controllers/services.

Example Usage

public class LittleNorthwindService
{
	private readonly LittleNorthwindCosmosContext _dbContext;

	public LittleNorthwindService(LittleNorthwindCosmosContext dbContext)
	{
		_dbContext = dbContext;
	}

	public async Task<Customer> AddCustomer(string firstName, string lastName, string emailAddress)
	{
		return await _dbContext.Customers.Add(
			new Customer()
			{
				FirstName = firstName,
				LastName = lastName,
				Email = emailAddress,
			});
	}

	public async Task<Customer> FindCustomer(string firstname, string lastname)
	{
		return _dbContext.Customers.Query(q => q
			.Where(c => c.FirstName == firstname && c.LastName == lastname)
			.OrderBy(c => c.FirstName))
			.FirstOrDefault();
	}

	public async Task<IEnumerable<Customer>> GetValuableCustomers(decimal dollarThreshold)
	{
		return _dbContext.Customers.Query(q => q
			.Where(c => c.TotalSpend > dollarThreshold)
			.OrderBy(c => c.TotalSpend));
	}

	// ... you get the idea ... //
	
}