DI in Azure Functions

Question

I have some class libraries that I use in my ASP.NET Web API app that handle all my backend stuff e.g. CRUD operations to multiple databases like Azure SQL Database, Cosmos

Answer 1

Azure Functions Depdendency Injection was announced at MSBuild 2019. Here's an example on how to do it:

[assembly: FunctionsStartup(typeof(MyNamespace.Startup))]

namespace MyNamespace
{
    public class Startup : FunctionsStartup
    {
        public override void Configure(IFunctionsHostBuilder builder)
        {
            builder.Services.AddHttpClient();
            builder.Services.AddSingleton((s) => {
                return new CosmosClient(Environment.GetEnvironmentVariable("COSMOSDB_CONNECTIONSTRING"));
            });
            builder.Services.AddSingleton();
        }
    }
}

• GitHub Example
• Documentation