This solution provides a starting point to build a web API to work with Azure Cosmos DB using ASP.NET Core and Azure Cosmos DB .NET SDK V3, based on Clean Architecture and repository design pattern.

• Partition key is also implemented through the repository pattern in order to support large scale Cosmos DB.
• A RESTful API application is created with popular architecture features (see full list below).

Clean Architecture is promoted by Microsoft on their .NET application architecture guide page. The e-book written by Steve "ardalis" Smith (@ardalis) is beautifully written and well explains the beauty and benefits of using Clean Architecture. For more details, please see Architect Modern Web Applications with ASP.NET Core and Azure

This project uses the newer Cosmos DB .NET SDK V3, because it adds support for stream APIs and Cosmos DB Change Feed processor APIs, as well as performance improvements.

(NEW) In addition to a REST API project, an Azure Functions starter project is also created to demonstrate how it can be used as a serverless computer service to work with Cosmos DB.

• Azure Functions project is also created with popular architecture features (see full list below).

(NEW) Auditing feature is added

• A default Audit container is created at API startup.
• Audit container use the entity id as the partition key, so that each entity record technically should have 20G worth of storage size avaiable to store audit log.
• Auditing is done automatically when updating an item.

⭐ If you enjoy this project, or are using this project to start your exciting new project, please give it a star. Thanks! ⭐

The primary goal of the project is to provide a basic solution structure for anyone who is building a new ASP.NET Core web or API project using Cosmos DB. Please watch for this repository to get notification when I make updates to the repo.

For a detailed discussion, please see my recent article, Clean Architecture — ASP.NET Core API using Partitioned Repository Pattern and Azure Cosmos DB (link: https://medium.com/swlh/clean-architecture-with-partitioned-repository-pattern-using-azure-cosmos-db-62241854cbc5)

1. Download the Azure CosmosDB emulator in order to run the API project locally. Here is a download link: https://docs.microsoft.com/en-us/azure/cosmos-db/local-emulator-release-notes#download.
2. Start the emulator
3. Set the API project as your Startup project in Visual Studio
4. The swagger UI page should be loaded at: https://localhost:5001/swagger/index.html

• ASP.NET Core 3.1
• Azure Cosmos DB .NET SDK V3
• Azure Functions V3 (new)
• Repository Design Pattern
• Horizontal Partitioning
• Partition Key Design
• REST API
• Swagger UI
• OData support
• IMemoryCache Cache service (Non-distributed in-memory cache)
• Serilog for structured logging
• MediatR Command/Query pattern
• MediatR pipeline behaviour for exception handling
• FluentValidation for validation
• AutoMapper to mapping
• Email Sender using SendGrid
• Cosmos DB Database initial creation
• Cosmos DB initial sample data seeding
• CRUD endpoints using Cosmos DB
• Cosmos DB point-read using partition key and ID
• Cosmos DB single-partition read and cross-partition read
• Search data in Cosmos DB using SQL query directly (demonstration purpose, not recommended in production)
• Search data in Cosmos DB using Parameterized Query
• Search data in Cosmos DB using LINQ and IQueryable
• Search data in Cosmos DB using Specification Pattern to abstract out query-specific logic
• Audit container and automatic auditing

• ASP.NET Core Identity (TODO)
• Identity Service (TODO)
• Cosmos DB Change Feed (TODO)
• Cosmos DB Stored Procedure for Transaction (TODO)
• SPA Client Application using React + Typescript (TODO)
• other TODOs

I have published some short articles to cover different aspects of this project. Please feel free to give them a read.

• Clean Architecture — ASP.NET Core API using Partitioned Repository Pattern and Azure Cosmos DB
• Clean Architecture — ASP.NET Core API Starter Project using In-memory Cache Service
• Clean Architecture — ASP.NET Core REST API with OData and Swagger UI
• Azure Cosmos DB — SQL Injection Attack and Defense

Special thanks to Steve Smith (@ardalis) for sharing the CleanArchitecture repository and the e-book. I absolutely love it!

Thanks to Azure-Samples/PartitionedRepository for sample code using Cosmos DB .NET SDK V2, which helped me understand Cosmos DB .NET SDK V2 and compare SDK V2 against V3.