F# Azure Function : Meta pairs from a web page head

This is my first real F# project - something I thought would be a minor stretch. I've done this type of work in C# but wanted to hone my chops with F# and work through getting serverless debug working locally. Here I want to use FSharp.Data to retrieve "meta" elements out of the head of a web page using the HTML Parser.

The Dev Container

As you can see from the devcontainer.json I added the REST client extension so that the HTTP test file can be used for debugging. I haven't set up a bash to pull the core tools and libraries necessary, but they're listed below. My default container image is Ubuntu 20 LTS.

wget -q https://packages.microsoft.com/config/ubuntu/20.04/packages-microsoft-prod.deb
sudo dpkg -i packages-microsoft-prod.deb
sudo apt-get update
sudo apt-get install azure-functions-core-tools-3
dotnet add package FSharp.Data

The good news is that this provides direct feedback for sample requests and can run as a stand-alone host on my build machine.

An Ionide Wrinkle (.NET Core 3.1 + .NET 5 = 💕 )

I felt a bit ham-strung by not seeing Ionide "light up" in VS Code within the container. After some whinging on the F# slack #beginners channel some clarity emerged that both .NET Core 3.1 an .NET 5 needed to be available in the container. This is because .NET 5 is used by Ionide to do the real-time parsing of the code against he compiler to inform the editor layout.

TODOs

There may be situations where certain openGraph tags are not available (and other fields would need to be substituted from the page). But I'll sort that out as I encounter issues. So far all of the pages I've pulled for placement in my site have had populated tags. So it will continue to run as-is in a dev container on my local build machine and it'll continue to serve up og meta tags requested by Hugo to be embedded in the static site pages.