In my latest post, I’ve shown you how you can use Azure Functions in your Microsoft Teams flow to handle errors in your environment. This stuff works great in a couple of projects I’ve worked on, but what would be even more awesome is to reply to a message in Teams when an action has completed after a button is pressed.

Well, replying & modifying the original message with a status update is quite possible and I’ll show you how in this post.

How do I send a reply to Microsoft Teams?

In the image below you can see a message having posted on my Teams channel and a reply is posted.

This reply has been sent from my Azure Function. If you want to do this, you need to send a HttpResponseMessage with a status code 200 and a specific header value. This header value is CARD-ACTION-STATUS and the value will be the message which you will see in the reply.

The code for this will look something similar to the following.

public static async Task<HttpResponseMessage> Run(
	[HttpTrigger(AuthorizationLevel.Function, "post", Route = null)] HttpRequest req,
	ILogger log)
{
	// Do your stuff...

	var result = new HttpResponseMessage
	{
		Headers =
		{
			{ "CARD-ACTION-STATUS", $"Timeout of `{request.Timeout}` miliseconds has expired."},
		},
		StatusCode = HttpStatusCode.OK
	};


	return result;
}

That’s all there is to it in order to send a single reply to your message.

So, a couple of weeks back I wrote about leveraging the power of Logic Apps to retrieve Alerts from within your Azure ecosystem and send them to Microsoft Teams. This works great and a fellow Azure MVP, Tom Kerkhove, has enhanced the Logic Apps Template when handling Azure Monitor events.I’m starting to become a pretty big van of Logic Apps, but there are some (obvious) downsides to it.

First, they live inside your Azure Portal. You can create, modify and export them from within the Portal, which is great, unless you want to integrate them in your ‘regular’ development cycle.The export feature enables you to copy/paste the Logic Apps to your ARM templates, but this is suboptimal in my opinion. There’s also the Azure Logic Apps Tools for Visual Studio extension, which makes the integration a bit better, but it still feels a bit quirky.Another downside is the ’language’. When exporting a Logic App you’ll be seeing a lot of JSON. While there might be a good reason for this, it’s not something I like working in and create (complex?) workflows.If you can overcome, or accept, these downsides I’d really advice you to look into Logic Apps. If not, well read on!

Azure Functions to the rescue

If your IT organization consists of mostly developers it might make more sense to use Azure Functions to glue different systems with each other instead of Logic Apps. The biggest downside of Azure Functions in this scenario is, you don’t have all of the building blocks from a Logic App to your availability. You have to create your own logic for this.However, the major benefit of using Azure Functions as the glue to your solution is they are written in the language of your choice and can be deployed via your ’normal’ CI/CD process.The only thing the Logic App in the previous post did was receive a HTTP POST message, parsing it and send a message to Teams. All of this can also be done via a standard HTTP triggered Azure Function. And because I prefer writing C# code instead of dragging-dropping building blocks (or write JSON if you’re really hardcore), the Azure Functions approach works best for me.

I’ve written about empowering your Teams with Azure Functions a while back, but this isn’t the only way to create value. You can also use Azure Logic Apps.

Logic Apps are a way to express powerful integrations with (several different) systems in a visual workflow based way. It has a lot of similarities with other (Microsoft) workflow systems from the past, so it should strike very familiar to most (Enterprise) developers.

Being a visual workflow solution, it doesn’t warm the heart of most developers. However, the world doesn’t consist solely of developers and this solution being visual is a very big advantage if you’re not a coder or like to deliver value instead of just more code.

First step

The first step you need (or actually, WANT) to take is create a Webhook connector on a channel. You can check my previous post on how to do this.

Posting to this channel has to be done in a similar way. You will still need to post some JSON in a predefined format to this webhook.

Next step: Setting up Alerts

In order to make your DevOps process a bit easier, it’s very useful to leverage the power of Application Insights and Alerts. For this to work, you need to know what metrics you actually want to be alerted for. I’m going to assume you already have some monitoring in place with appropriate metrics. If not, you should definitely define some. They can be tuned afterward.

In today’s world we’re receiving an enormous amount of e-mail.

A lot of the e-mail I’m receiving during the day (and night) is about errors happening in our cloud environment and sometimes someone needs to follow up on this.

At the moment this is a real pain because there’s a lot of false-positives in those e-mails due to the lack of configuration and possibilities in our monitoring software. The amount of e-mails is so painful, most of us have created email rules so these monitoring emails ‘go away’ and we only check them once per day. Not really an ideal solution.

But what if I told you all of this pain can go away with some serverless magic and the power of Microsoft Teams. Sounds great, right?

How to integrate with Microsoft Teams?

This is actually the easiest part if you’re a developer.

If you’re already running Microsoft Teams on your Office 365 tenant, you can add a channel to a team to which you belong and add a Webhook connector to it. I’ve created a channel called Alerts on which I added an Incoming Webhook connector.

After having saved the connector you’ll be able to copy the actual webhook URL which you need to use in order to POST messages to the channel.

The default Azure Functions runtime comes with quite a lot of bindings and triggers which enable you to create a highly scalable solution within the Azure environment. You can connect to service buses, storage accounts, Event Grid, Cosmos DB, HTTP calls, etc.

However, sometimes this isn’t enough.

That’s why the Azure Functions team has released functionality which enables you to create your own custom bindings. This should make it easy for you to read and write data to any service or location you need to, even if it’s not supported out of the box.

There is some documentation available on how to create a custom binding at this time and even a nice sample on GitHub to get you started. The thing is this documentation and samples are written for Version 1 of the Azure Functions runtime. If you want to use custom bindings in Azure Functions V2, you need to do some additional stuff. There are still changes being made on this subject, so it’s quite possible the current workflow will be broken in the future.

For this post, I’ve created a sample binding which is capable of reading data from a local disk. Nothing fancy and definitely not something you want in production, but it’s easy to test and shows you how the stuff has to be set up.

There’s a relative new feature available in Azure called Managed Service Identity. What it does is create an identity for a service instance in the Azure AD tenant, which in its turn can be used to access other resources within Azure. This is a great feature, because now you don’t have to maintain and create identities for your applications by yourself anymore. All of this management is handled for you when using a System Assigned Identity. There’s also an option to use User Assigned Identities which work a bit different.

Because I’m an Azure Function fanboy and want to store my secrets within Azure Key Vault, I was wondering if I was able to configure MSI via an ARM template and access the Key Vault from an Azure Function without specifying an identity by myself.

As most of the things, setting this up is rather easy, once you know what to do.

The ARM template

The documentation states you can add an identity property to your Azure App Service in order to enable MSI.

"identity": {
    "type": "SystemAssigned"
}

This setting is everything you need in order to create a new service principal (identity) within the Azure Active Directory. This new identity has the exact same name as your App Service, so it should be easy to identify.

As I mentioned in my earlier post, there are 2 options available to you out of the box for logging. You can either use the TraceWriter or the ILogger. While this is fine when you are doing some small projects or Functions, it can become a problem if you want your Azure Functions to reuse earlier developed logic or modules used in different projects, a Web API for example.

In these shared class libraries you are probably leveraging the power of a ‘full-blown’ logging library. While it is possible to wire up a secondary logging instance in your Azure Function, it’s better to use something which is already available to you, like the ILogger or the TraceWriter.

I’m a big fan of the log4net logging library, so this post is about using log4net with Azure Functions. As it goes, you can apply the same principle for any other logging framework just the implementation will be a bit different.

Creating an appender

One way to extend the logging capabilities of log4net is by creating your own logging appender. You are probably already using some default file appender or console appender in your projects. Because there isn’t an out-of-the-box appender for the ILogger, yet, you have to create one yourself.

Creating a solution with multiple small services is great of course. It provides you with a lot of flexibility and scalability.

There are however a couple of things you have to think about when designing and developing a solution with multiple services. One of the things you need to figure out is how to implement proper logging. For an actual production system you need to have this in place in order to monitor and debug the overall solution.

We, developers using Azure Functions, are already blessed with some logging mechanisms and tools provided out of the box! The out of the box stuff is pretty basic, but it gets the job done and will make your life much easier when the need arises to analyze a production issue.

Logging in your function

When first creating your Azure Function you will probably see a parameter being passed in your Run method called log.

public static class Function1
{
    [FunctionName("Function1")]
    public static async Task<HttpResponseMessage> Start(
        [HttpTrigger(AuthorizationLevel.Anonymous, "get", Route = null)]
        HttpRequestMessage req,
        TraceWriter log)
    {
        log.Info("C# HTTP trigger function processed a request.");
        // Logic
    }
}

This log-parameter can be used to do some simple logging inside your Azure Function. When invoking this function you’ll be able to see the specified log entry in your console.

In a couple of weeks, on the 22nd of February, I’ll be talking at a free event organized by 4DotNet and SnelStart called Move Up with Azure. I’m not the only one who will be speaking over there, there’s also a great session by Henry Been (SnelStart) and an awesome talk from Christos Matskas (Microsoft).

I myself will be talking on how to create a serverless solution using Azure Functions. This of course is a very broad subject and I’d like to know what you think I should focus on or what you would like to see covered in this session?

Some areas which I’ll be covering for sure is a short introduction on the serverless paradigm, how to design and create a scalable architecture, using built-in functionality offered by Azure Functions to make your life easier, working with Visual Studio to get stuff done and of course how to test your solution.

There are a lot of other subjects which I can also cover and deep-dive into. Feel free to comment over here if you have a specific interest in something related to serverless or Azure Functions. For example Durable Functions, performance, common patterns & principles.

Hope to see you on the 22nd of February in Nieuwegein. Be sure to register on Eventbrite to get your free ticket for this event!

Using certificates to secure, sign and validate information has become a common practice in the past couple of years. Therefore, it makes sense to use them in combination with Azure Functions as well.

As Azure Functions are hosted on top of an Azure App Service this is quite possible, but you do have to configure something before you can start using certificates.

Adding your certificate to the Function App

Let’s just start at the beginning, in case you are wondering on how to add these certificates to your Function App. Adding certificates is ‘hidden’ on the SSL blade in the Azure portal. Over here you can add SSL certificates, but also regular certificates

Keep in mind though, if you are going to use certificates in your own project, please just add them to Azure Key Vault in order to keep them secure. Using the Key Vault is the preferred way to work with certificates (and secrets).

For the purpose of this post I’ve just pressed the Upload Certificate-link, which will prompt you with a new blade from which you can upload a private or public certificate.

You will be able to see the certificate’s thumbprint, name and expiration date on the SSL blade if it has been added correctly.