Building SOAP Listener with Azure Functions

Question

I am using Azure Functions to build some integrations between various systems. I new requirement is to respond to record updates in Salesforce. Some quick research yielded what seems like a good solution from the Salesforce side. Use Outbound messaging which can send SOAP requests on record modifications.

How to create Salesforce application that will send record to external web service when record created/changed(https://salesforce.stackexchange.com/questions/73425/how-to-create-salesforce-application-that-will-send-record-to-external-web-servi)

The challenge now is to be able create a SOAP listener in Azure Function. I have created basic HTTP Triggers for my other listeners. Is there anything "built-in" to Azure Functions that would allow me to easily consume the incoming SOAP request?

Salesforce has the basics for a solution based on a more traditional web service and an ASMX file but I am not sure if or how that can be applied in Azure Functions. (https://developer.salesforce.com/docs/atlas.en-us.api.meta/api/sforce_api_om_outboundmessaging_listener.htm)

Answer 1

That notification is just a SOAP request that is made over HTTP, so really not too different than a regular HTTP trigger request.

Although you could just treat that as a plain request and parse the contents yourself, Azure Functions does expose the great WebHook support we get from ASP.NET WebHooks, and luckily, there is a Salesforce receiver that significantly simplifies this task.

DISCLAIMER: It's worth noting that although the receiver is technically enabled in Azure Functions, there's no official support for it yet, so you won't find a lot of documentation and help will be limited to what you get on SO and Forums. Official support to this and other receivers will hopefully be coming soon, which means documentation, templates and UI support will become available.

To get started, you need the following:

• Create a new function, selecting the GenericWebHook - CSharp template (this works for node as well, but I'll focus on C# here.
• Follow the steps outlined on the ASP.NET WebHooks integration with Salesforce post in order to create the outbound message. Here you want to use the Function Url given to you by the portal WITHOUT THE CODE QUERY STRING (having the code there wouldn't hurt, but the receiver does not use that information).
  • IMPORTANT: Get your Salesforce Organization ID, which will be used for authentication and is located under Administer > Company Profile > Company Information > Salesforce.com Organization ID and back in the Azure Functions portal, open the Keys panel, delete your default function key (not host key) and create a new key, named default (this name is important) using the Organization ID value you got from Salesforce.
• Go to Integrate
  • On the integration page, select Advanced Editor on the upper right (as mentioned, there's no official support, so the UI does not expose this. We're putting our explorer hats on and venturing into a more advanced workflow here :) )
  • Change the webHookType property value to sfsoap and save the configuration. Your function.json config should look like the following:

function.json:

{
  "bindings": [
    {
      "type": "httpTrigger",
      "direction": "in",
      "webHookType": "sfsoap",
      "name": "req"
    },
    {
      "type": "http",
      "direction": "out",
      "name": "res"
    }
  ],
  "disabled": false
}

• Switch to the Develop tab. We're ready to write our code.

This is where the ASP.NET WebHooks receiver shines! It will parse the notification for you, exposing strong typed objects you can work with. All you need to do is modify the method/function signature you get withe template to use the SalesforceNotifications type, making sure you're referencing the required assembly (Microsoft.AspNet.WebHooks.Receivers.Salesforce, which is made available to you, so no need for package reference) and namespace reference (Microsoft.AspNet.WebHooks).

Here is a full sample of a function that will receive the request and log the Organization ID, Action ID, grab the first notification and log all of its properties:

#r "Microsoft.AspNet.WebHooks.Receivers.Salesforce"
using Microsoft.AspNet.WebHooks;

public static void Run(SalesforceNotifications req, TraceWriter log)
{
    log.Info($"Salesforce webhook was triggered!");

    log.Info(req.OrganizationId);
    log.Info(req.ActionId);

    var notification = req.Notifications.First();

    foreach (var p in notification.Keys)
    {
        log.Info($"{p} = {notification[p]}");
    }
}

This process will be a lot smoother when the receiver is officially supported, but even with the added steps, this still beats having to parse the SOAP messages yourself :)

I hope this helps!