Assuming you have an Azure account, login to the portal. If you don’t yet, Getting Started with Azure is Easy and Free.

Once you’re logged in, click "+ New" and search for Couchbase Server in the marketplace. I’m using BYOL (bring your own license) for demonstration, but there is also an "Hourly Pricing" option that comes with silver support.

Once you select Couchbase, you’ll be taken through an Azure installation wizard. Click the "Create" button to get started.

Step 1 is the "Basics". Fill out the username and password you want for Couchbase, the name of a resource group, and a location (I chose North Central US because it is close to me geographically). Make sure to make a note of this information, as you’ll need it later.

The next step is Couchbase Config. There are some recommended VM types to use. I went with DS1_V2 to keep this blog post cheap, but you probably want at least 4 cores and 4gb of RAM for your production environment. I also elected not to install any Sync Gateway Nodes, but if you plan to use Couchbase Mobile, you will need these too. I’m asking for a total of 3 nodes for Couchbase Server.

After this, step 3 is just a summary of the information you’ve entered.

The last step is "buy". This shows you the terms. One "Create" button is all that remains.

Now, Azure will go to work provisioning 3 VMs, installing Couchbase Server on them, and then creating a cluster. This will take a little bit of time. You’ll get an Azure notification when it’s done.

You should have just enough time to get yourself a nice beverage.

When Azure finishes with deployment, go look at "Resource groups" in the Azure portal. Find your resource group. Mine was called my_cb_resource_group.

Click on the resource group. Inside that resource group, you’ll see 4 things:

First, click 'server', and then 'instances'. You should see 3 servers (or however many you provisioned).

Next, click 'deployments'. You should see one for Couchbase listed. Click it for more information about the deployment.

The next screen will tell you the URL that you need to get to the Couchbase Server UI (and Sync Gateway UI if you installed that). It should look something like: http://vm0.server-foobarbazqux.northcentralus.cloudapp.azure.com:8091.

Paste that URL into a browser. You will be taken to the Couchbase Server login screen. Use the credentials you specified earlier to login.

After you login, click on 'servers'. You will see the three servers listed here. The URLs will match the deployments you see in the Azure portal.

Let’s put some data in this database! Go to Settings → Sample Buckets and load the 'travel-sample' bucket.

This sample data contains 31591 documents. When it’s done loading, go back to "servers". You can see how the 'items' (and replica items) are evenly distributed amongst the three servers. Each node in Couchbase can do both reads and writes, so this is not a master/slave or a read-only replica sets situation.

Now, let’s suppose your application is really taking off, and you need to scale up to provide additional capacity, storage, performance. Since we’re using Couchbase deployed from the Azure marketplace, this is even easier than usual. Go to the Azure portal, back to the resource group, and click "server" again. Now click "scaling"

Next, you will see a slider that you can adjust to add more instances. Let’s bump it up to 5 total servers. Make sure to click "save".

Now, go back to 'instances' again. Note: you may have to refresh the page. Azure doesn’t seem to want to update the stale page served to the browser on its own. You will now see server_3 and server_4 in "creating" status.

You will need to wait for these to be deployed by Azure. In the meantime, you can go back over to the Couchbase Server UI and wait for them to appear there as well.

When adding new servers, the cluster must be rebalanced. The Azure deployment should attempt to do this automatically (but just in case it fails, you can trigger the rebalance manually too).

During this rebalance period, the cluster is still accessible from your applications. There will be no downtime. After the rebalance is over, you can see that the # of items on each server has changed. It’s been redistributed (along with replicas).

That’s it. It’s pretty much just moving a slider and waiting a few minutes.

At some point, you may want to scale down your cluster. Perhaps you need 5 servers during a certain part of the year, but you only need 3 for other parts, and you’d like to save some money on your Azure bill.

Once again, this is just a matter of adjusting the slider. However, it’s a good idea to scale down one server at a time to avoid any risk of data loss.

When you scale down, Azure will pick a VM to decommission. Couchbase Server can respond in one of two ways:

I’m going to leave auto-failover off and show the default behavior.

First, the server will show a status of 'deleting' in the Azure portal.

Soon after, Couchbase will recognize that a node is not responsive. It will suggest failover to 'activate available replicas'.

I’ll go ahead and do just that.

Once it’s removed from the cluster, you’ll need to trigger a 'rebalance'.

Scaling a Couchbase cluster on Azure is simply a matter of using the slider.

If you’re scaling down, consider doing it one node at a time.

For more information, check out these resources:

If you have questions, please contact me on Twitter @mgroves or leave a comment.

I’m going to assume some level of familiarity with ASP.NET Core and creating a REST API. Here’s an example of a GET and a POST. These endpoints are reading/writing from a JSON text file (in a way that is probably not thread-safe and definitely not efficient, but it’s fine for this example).

To try out the GET endpoint, the simplest thing I can do is open a browser and view the results. But to try out the POST endpoint, I need something else. I could install Postman or Fiddler (and you should). Here’s how that would look.

Postman is great for interacting with endpoints, but Postman alone doesn’t really tell us anything about the endpoint or the system as a whole. This is where Swagger comes in.

Swagger is a standard way to provide specifications for endpoints. Usually, that specification is automatically generated and then used to generate an interactive UI.

We could write the Swagger spec out by hand, but fortunately ASP.NET Core provides enough information to generate a spec for us. Look at the PostTeam action above. Just from reading that we know:

From that, we could construct a Swagger spec like the following (I used JSON, you can also use YAML).

But why on earth would you want to type that out? Let’s bring in a .NET library to do the job. Install Swashbuckle.AspNetCore with NuGet (there’s a different package if you want to do this with ASP.NET).

You’ll need to add a few things to Startup.cs:

In the ConfigureServices method:

In the Configure method:

Aside: With ASP.NET, NuGet actually does all this setup work for you.

Once you’ve done this, you can open a URL like http://localhost:9119/swagger/v1/swagger.json and see the generated JSON spec.

That spec is nice, but it would be even nicer if we could use the spec to generate a UI.

Back in the Configure method, add this:

Now, open your site and go to /swagger:

Some cool things to notice:

Swagger and Swashbuckle have done a lot with just a little bit. It can do even more if we add a little more information in the code.

(Also make sure you XML Documentation output for your project enabled)

Here’s an example of a GetTeams method with both XML comments and ProducesResponseType:

Here’s a screenshot of the UI that has all three of the above enhancements: response type, XML comments, and more customized info.

Working on HTTP-based APIs? Bring Swashbuckle and Swagger into your life!

More resources:

Thanks again for reading the 2017 C# Advent!

I could have chosen a lot of different platforms to create a chatbot for: Facebook Messenger, Skype, WhatsApp, and more. But I decided to go with Viber.

In the United States, Viber doesn’t seem to have a huge following, but I’ve been using it a lot. It’s a very handy way to chat with my wife, send pictures, funny GIFs, and so on. I find it to be more reliable and faster than SMS, especially for pictures. I wish everyone in my family was using it! It’s also a nice side effect that Viber is a Couchbase customer. They switched from MongoDb to support their growing data needs.

Also, Viber’s REST API is simple and well documented. Between the use of serverless architecture and Viber’s API, I couldn’t believe how fast I went from 0 to chatbot.

First, You’ll need to start by creating a bot in Viber (you’ll need a Viber account at some point). Viber will give you an API key that looks something like 30a6470a1c67d66f-4207550bd0f024fa-c4cacb89afc04094. You’ll use this in the HTTP headers to authenticate to the Viber API.

Next, create a new Azure Functions solution. I’ve previously blogged about Azure Functions with a followup on Lazy Initialization.

I decided to use C# to write my Azure Functions. Unfortunately, there is no .NET SDK for Viber (as far as I know), so I’ll have to use the REST API directly. Not a big deal, I just used RestSharp. But if you prefer NodeJS or Python, Viber has got you covered with SDKs for those languages.

Before you start coding, you’ll need to setup a Webhook. This is simply a way of telling Viber where to send incoming messages. You’ll only need to do this at the beginning. I did this by first deploying a barebones Azure Function that returns a 200. I used Postman to set the initial webhook.

Finally, I setup a Couchbase cluster on Azure. Getting started with Couchbase and Azure is easy and free. (You can even use the "Test Drive" button to get 3 hours of Couchbase Server without expending any Azure credit). I created a single user called "viberchatbot", a bucket called "ViberChatBot", and I loaded the "travel-sample" bucket.

For this application, I wanted to create a chatbot with a little more substance than "Hello, world" and I also wanted to have a little fun. Here are the commands I want my chatbot to understand:

I decided not to use any natural language processing or parsing libraries. I’m just going to use simple if/else statements and some basic string matching. If you are planning to create a robust chatbot with rich capabilities, I definitely recommend checking out libraries and tools like LUIS, wit.ai, NLTK and others.

I started by creating a few C# classes to represent the structure of the data that Viber will be sending to my serverless endpoint.

That’s all the basics. Check out the source code for the complete set of actions/operations that the chatbot can do. To test out the bot, I used my Viber app for Android on my phone (and my wife’s, to make sure it worked when I went public).

Beware: by the time you read this, the chatbot I created will likely be taken offline. Anyone else who creates a "Couchbase Bot" is not me!

Here’s a recap of the benefits of this approach to creating a chatbot:

This was really fun, and I could definitely get carried away playing with this new chatbot. It could analyze images, tell jokes, look up all kinds of information, sell products and services, or any number of useful operations.

I would love to hear what you’re doing with chatbots! Please leave a comment or contact me on Twitter @mgroves.

With serverless, you simply write code (usually in form of functions/methods). You can do so with many popular languages, including C#, JavaScript (Node), Java, and so on. This code is deployed to a cloud provider like Microsoft Azure, Amazon Web Services (AWS), Google Cloud Platform (GCP), and more.

Your code is triggered by events. Events can be as simple as HTTP requests, or they could be many other types of events, depending on what the cloud platform supports. (Azure, for instance, supports Timer, GitHub, etc).

Within the cloud, the servers that execute that code are automatically provisioned (and decommissioned) by the cloud provider on an as-needed basis.

You might also see the terms BaaS (Backend as a Service) or FaaS (Function as a Service). Recently, the meaning of the "serverless" buzz word has been expanded, but this post mainly focuses on FaaS/BaaS cloud services.

There are some similarities between serverless and microservices, but they are not the same thing. Both are approaches to break an application into smaller, independent pieces. They differ in what is deployed and what you manage.

As an example, if you are using a microservice architecture, you might have a "shopping cart" service (in addition to other services like "user profile", "inventory", etc). Here’s a diagram of a very simple microservice.

Notice some properties of the microservice:

Contrast this with a similar set of features, this time created with a serverless approach.

In the serverless architecture,

Shown in the above diagram are only standard HTTP requests. You could also use a Timer event, for instance, to check every 5 minutes to see if there are any abandoned shopping carts.

There are some benefits (and trade-offs) when using a serverless architecture.

One benefit is that scalability is handled by the cloud provider. If demand or usage increases, the cloud provider can compensate by adding more server(s) when necessary.

Another benefit is that costs are tied to usage. If you have a service that is constantly in use, you might not see any benefits. But if you have a service that is sporadically used, then serverless may provide cost savings.

Finally, it’s possible that a serverless architecture can reduce administration costs. You don’t need to wait for a server to be commissioned. This may improve agile iteration if commissioning VMs or servers are time consuming. It can reduce your need for IT operations, at least initially, because there are no servers to deploy, fewer servers to manage/upgrade/etc. All this may lead to improved developer productivity.

It’s important to note that serverless is not a silver bullet. Your application may not be a good fit for this kind of decomposition. Also, if you end up deploying a large number of serverless functions, you will still need operations people to manage, monitor, and test your functions. Definitely check out the benefits and drawbacks in detail at MartinFowler.com.

There are several popular serverless providers:

Couchbase Server has partnered with each of these major cloud providers and can run on any of those platforms. In addition, you can run Couchbase Server across multiple cloud vendors for improved reach, disaster recovery, and diversification. You can also use Couchbase Server in a hybrid-cloud situation (a mix of cloud and on-premises).

This makes Couchbase a great choice when you need a NoSQL document database, no matter your cloud strategy:

No vendor lock in. With Couchbase, you aren’t even locked into the cloud, much less a single cloud vendor. With XDCR, you can go cloud-first, and have an on-premises cluster for disaster recovery, or deploy Couchbase to multiple clouds.

Cloud marketplace offerings. You can get started in minutes: on Microsoft Azure, AWS, or GCP.

Tools for your programming language. Couchbase offers SDKs for Node.js, .NET, Java, PHP, Python, Go, C/C++, as well as community support for many others. No matter your serverless platform or language preferences, Couchbase has you covered. Check out this blog post on Azure Functions with Couchbase Server for a technical intro using .NET/C#/Azure.

Scaling. With Couchbase Server, scaling is easy and efficient. Couchbase’s architecture is designed for scaling, with built-in replication, autosharding, and data distribution. Every node in a Couchbase cluster can do both reads and writes, providing efficient use of computing resources and high availability.

Flexibility of JSON. Many apps can benefit from a flexible schema, even if you’re using a relational database. Check out this whitepaper on why Couchbase is the engagement database that can work alongside your transactional and analytical database to provide an exceptional customer experience.

Serverless takes decomposition of your application back-end one step further.

Storing JSON data in Couchbase Server gives you flexibility with both schema and scaling.

Is serverless right for you? It’s not a silver bullet, but if you’re interested in benefiting from lower costs and easier deployment, we’d be happy to help you create a careful plan and discuss whether or not it’s a right fit for your application. You can contact me by leaving a comment, or finding me on Twitter @mgroves.