Centralized Configuration for .NET Core using Azure Cosmos DB and Narad

We are living in a micro services world. All these services are generally hosted in Docker container which are ephemeral. Moreover these service need to start themselves up, talk to each other, etc. All this needs configuration and there are many commercially available configuration providers like Spring Cloud Config Server, Consul etc. These are excellent tools which provide a lot more functionality than just storing configuration data. However all these have a weakness - they have a single point of failure - their storage mechanism be it a file system, database etc. There are ways to work around those but if you want a really simple place to store configuration values and at the same time make it highly available, with guaranteed global availability and millisecond reads, what can be a better tool than Azure Cosmos DB!

So I set forth on this journey for ASP.NET Core projects to talk to Cosmos DB to retrieve their configuration data. For inspiration I looked at Steeltoe Configuration Provider and modified it to support Azure Cosmos DB. Enter Narad - an Azure Cosmos DB Configuration Provider for .NET Core.

To use Narad, first create a Cosmos DB database and upload your configuration data as JSON file in one of the collection. There are excellent instructions available on MSDN docs on how to do this. Next clone or download it from GitHub repository and add the reference to "Narad.Extensions.Configuration.CosmosDBCore". Narad is now available as a Nuget package. Search for "Narad.Extensions.Configuration.CosmosDBCore" or follow this link - https://www.nuget.org/packages/Narad.Extensions.Configuration.CosmosDBCore/.Also in your appsettings.json, you will have to provide the following details:

The database and collection name can be whatever you want. Next in Program.cs, add the AddCosmosDB() method. You are done! Optionally you can also bind your configuration POCO class to the configuration values retrieved from Cosmos DB as shown in the Startup.cs.

You can find the complete source code as well as sample client on GitHub - https://github.com/mayankthebest/Narad