he9lin / fsharp-demonstrator

A sample server-side web app with support to run in the Azure App Service

Hosting F# in a web application on Azure

This repo is designed to showcase some F# features whilst at the same time also giving some examples of how to host your F# applications within a web-facing application and also to host it within Azure. Examples are provided for both ASP .NET Web API as well as Suave.

F# Web Applications

ASP .NET Web API

Example shown illustrates how to host some self-contained F# business logic assembly within a simple OWIN-based ASP .NET Web API project.

Suave

Example shown illustrates how to host the same F# business logic assembly within a Suave application and routing.

Azure Hosting

Azure Resource Manager (ARM) Template

ARM templates allow you to specify declaratively how to create an application. A resource template is included to allow you to deploy all infrastructure from a single script: -

• App Hosting Plan
• App Service
• App Insights
• Configuration Settings for App Service based on App Insights

Suave integration

A web.config file is provided within the Suave application which is used when hosting Suave executables within the Azure App Service. Essentially IIS acts as a pass-thru to allow you to forward all requests directly to the Suave application.

App Insights integration

Some code has been added to the Suave application to allow easy App Insights integration, which captures e.g. requests, events, tracing and even dependency tracking e.g. HTTP, Azure and SQL calls.

Source Code deployment

Support is provided for direct deployment from source code e.g. GitHub directly to Azure App Service. This is enabled through the build.cmd file, which utilises Azure's Kudu framework to perform builds via calling: -

• Paket bootstrapper (download Paket)
• Paket restore (download Nuget dependencies)
• MSBuild (build source code)
• Kudu Sync (diff MSBuild outputs with previous deployment)

Note that the .deployment file is used to tell Kudu which command to run whenever a push occurs to e.g. the Git repository.

Web Jobs

A simple example of a Web Job running directly via an F# script is supplied (sample.fsx). This script is copied as part of the build.cmd process to the webjobs folder within the App Service (e.g. app_data\jobs\continuous\Sample). The web job simply runs every 30 seconds and writes to a local file.