This is a simple .NET Core web app using Razor pages and MVC. It was created from the dotnet new webapp template and modified adding Bootstrap v4, Fontawesome and other packages/features.

The app has been designed with cloud native demos & containers in mind, in order to provide a real working application for deployment, something more than "hello-world" but with the minimum of pre-reqs. It is not intended as a complete example of a fully functioning architecture or complex software design.

Typical uses would be deployment to Kubernetes, demos of Docker, CI/CD (build pipelines are provided), deployment to cloud (Azure) monitoring, auto-scaling

The app has several basic pages accessed from the top navigation menu, some of which are only lit up when certain configuration variables are set (see 'Optional Features' below):

• 'Info' - Will show system & runtime information, and will also display if the app is running from within a Docker container and Kubernetes.
• 'Tools' - Some tools useful in demos, such a forcing CPU load (for autoscale demos), and error/exception pages for use with App Insights or other monitoring tool.
• 'Monitoring' - Displays realtime CPU load and memory working set charts, fetched from an REST API (/api/monitoringdata) and displayed using chart.js
• 'Weather' - (Optional) Gets the location of the client page (with HTML5 Geolocation). The resulting location is used to fetch a weather forecast from the Dark Sky weather API
• 'User Account' - (Optional) When configured with Azure AD (application client id and secret) user login button will be enabled, and an user-account details page enabled, which calls the Microsoft Graph API

cd src
dotnet restore
dotnet run

Web app will listen on the usual Kestrel port of 5000, but this can be changed by setting the ASPNETCORE_URLS environmental variable or with the --urls parameter (see docs).
Tested with Dotnet Core v3.0 and 3.1

Public Docker image is available on GitHub Container Registry.

Run in a container with:

docker run --rm -it -p 5000:5000 ghcr.io/benc-uk/dotnet-demoapp:latest

Should you want to build your own container, use the Dockerfile at the root of the project

The app will start up and run with zero configuration, however the only features that will be available will be the Info, Tools & Monitoring views. The following optional features can be enabled:

Enable this by setting ApplicationInsights__InstrumentationKey

The app has been instrumented with the Application Insights SDK, it will however need to be configured to point to your App Insights instance/workspace. All requests will be tracked, as well as dependant calls to other APIs, exceptions & errors will also be logged

This article has more information on monitoring .NET Core with App Insights

If running locally, and using appsettings.json, this can be configured as follows

  "Weather": {
    "ApiKey": "{{ key value here }}"
  },

Enable this by setting Weather__ApiKey

This will require a API key from Dark Sky, you can sign up for free and get one here. The page uses a browser API for geolocation to fetch the user's location.
However, the geolocation.getCurrentPosition() browser API will only work when the site is served via HTTPS or from localhost. As a fallback, weather for London, UK will be show if the current position can not be obtained

If running locally, and using appsettings.json, this can be configured as follows

  "Weather": {
    "ApiKey": "{{ key value here }}"
  },

Enable this feature by setting several 'AzureAd' environmental variables, once enabled, a 'Login' button will be displayed on the main top nav bar.

This uses Microsoft.Identity.Web which is a library allowing .NET Core web apps to use the Microsoft Identity Platform (i.e. Azure AD v2.0 endpoint). As this library is not available as NuGet package yet, it is included in this repo in the 'external' directory.

In addition the user account page shows details & photo retrieved from the Microsoft Graph API

You will need to register an app in your Azure AD tennant. See this guide. Make sure you enable the options

• Enable the app for "Accounts in any organizational directory and personal Microsoft accounts"
• Add 'Web platform' for authentication
• Ensure your Redirect URI ends with /signin-oidc
• Enable "Access Tokens" and "ID Tokens" in the authentication settings.
• Add a new client secret, and make a note of it's value

Environmental Variables:

• AzureAd__ClientId: You app's client id
• AzureAd__ClientSecret: You app's client secret
• AzureAd__Instance: Set to https://login.microsoftonline.com/
• AzureAd__TenantId: Set to common
• AzureAd__CallbackPath: Set to /signin-oidc

If running locally, and using appsettings.json, this can be configured as follows

  "AzureAd": {
    "Instance": "https://login.microsoftonline.com/",
    "ClientId": "9c8ff43e-73da-4db3-815a-22f457cec7f0",
    "ClientSecret": "{{ secret value here }}",
    "TenantId": "common",
    "CallbackPath": "/signin-oidc"
  },

If you want to deploy to an Azure Web App as a container (aka Linux Web App), a Bicep template is provided in the infrastructure as code directory

You can also very quickly deploy to Azure App Service directly with the Azure CLI and az webapp up. Note. <app-name> must be globally unique. Change the sku to a larger size, e.g. P1V2 for a much faster deployment

cd src
az webapp up --sku F1 --name <app-name>

• Nov 2020 - Updated to .NET 5
• Nov 2020 - New GitHub pipelines & container registry
• Jun 2020 - Moved to NuGet for the Microsoft.Identity.Web
• Jan 2020 - Rewritten from scratch