This repo contains a sample project to demonstrate the architecture and plumbing needed when writing a custom binding in Azure Functions v2 for the MessageBird API. It also contains a sample implementation function written in C#. Using this as a starting point should help you understand what's going on, and help you integrate with MessageBird on Azure.
NOTE: The code provided here is sample code, please use as reference only and don't just copy straight into production. It has no warranty.
To use the binding, register a new developer account with https://messagebird.com. Put the sms webhook url (https://rest.messagebird.com/messages) in local.settings.json (add this file to the ExampleCSharp project) with the key MessageBirdWebHookUrl. Put your API key in local.settings.json with the key MessageBirdApiKey.
For more info see https://docs.microsoft.com/nl-nl/azure/azure-functions/functions-run-local.