Tag Archives: dotnet
Implement a secure MCP server using OAuth and Entra ID
The article shows how to implement a secure model context protocol (MCP) server using OAuth and Entra ID. The MCP server is implemented using ASP.NET Core and uses Microsoft Entra ID to secure the API. An ASP.NET Core application using Azure OpenAI and semantic kernel is used to implement the MCP client for the agent […]
Handling OpenID Connect error events in ASP.NET Core
ASP.NET Core provides great extension points for handling OpenID Connect error events. This blog looks at implementing error handling in an ASP.NET Core application implemented using ASP.NET Core Identity. Code: https://github.com/damienbod/IdentityExternalErrorHandling Setup The application uses OpenID Connect to implement the authentication of the user identities. This implements a standard OpenID Connect flow and uses Microsoft […]
Implement client assertions with client credentials flow using OAuth DPoP
This blog looks at implementing client assertions for the client credentials flow using OAuth 2.0 Demonstration of Proof-of-Possession (DPoP). The client credentials flow is an OAuth 2.0 authorization grant type used for machine-to-machine authentication. DPoP further strengthens the security by ensuring that the client possesses a specific key at the time of the request, forcing […]
ASP.NET Core delegated Microsoft OBO access token management (Entra only)
This blog shows how to implement a delegated Microsoft On-Behalf-Of flow in ASP.NET Core, and has a focus on access token management. The solution uses Microsoft.Identity.Web to implement the different flows and it really simple to implement, when you know how to use the Nuget package and use the correct Microsoft documentation. The application can […]
Implement Phone verification, 2FA using ASP.NET Core Identity
This post shows how to implement phone (SMS) verification and two-factor authentication (2FA) using ASP.NET Core Identity. The solution integrates phone-based verification and 2FA mechanisms. The implementation uses ASP.NET Core Identity’s extensibility to incorporate SMS-based verification during user registration and login processes. SMS is no longer a recommended authentication method due to security risks but […]
Customizing a single client sign-in using parameters in Duende IdentityServer
This post looks at customizing the sign-in UI and the sign-in options in an ASP.NET Core application using Duende IdentityServer and ASP.NET Core Identity. There are multiple ways of changing the look and feel of the UI for different OpenID Connect clients or different client flows. In the previous post, the UI was customized per […]
ASP.NET Core user delegated access token management
The article looks at managing user delegated access tokens for a downstream API in an ASP.NET Core web application. There are many ways of implementing this, all with advantages and disadvantages. The tokens are requested from an OpenID Connect server using the recommended standards. In this blog, the UI access token from the application authentication […]
Implement a Geo-distance search using .NET Aspire, Elasticsearch and ASP.NET Core
This article shows how to implement a geo location search in an ASP.NET Core application using a LeafletJs map. The selected location can be used to find the nearest location with an Elasticsearch Geo-distance query. The Elasticsearch container and the ASP.NET Core UI application are setup for development using .NET Aspire. Code: https://github.com/damienbod/WebGeoElasticsearch Setup For […]
Using Elasticsearch with .NET Aspire
This post shows how to use Elasticsearch in .NET Aspire. Elasticsearch is setup to use HTTPS with the dotnet developer certificates and and simple client can be implemented to query the data. Code: https://github.com/damienbod/keycloak-backchannel Setup Two services are setup to run in .NET Aspire. The first service is the official Elasticsearch docker container and deployed […]
Implement ASP.NET Core OpenID Connect OAuth PAR client with Keycloak using .NET Aspire
This post shows how to implement an ASP.NET Core application which uses OpenID Connect and OAuth PAR for authentication. The client application uses Keycloak as the identity provider. The Keycloak application is hosted in a docker container. The applications are run locally using .NET Aspire. This makes it really easy to develop using containers. Code: […]
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