Serverless and microservices architectures are two major approaches to building modern web apps, and they often go hand-in-hand. Both follow the same structural principles, and both oppose monolithic architecture, prioritizing scalability, flexibility, and cost-effectiveness instead.
Still, serverless and microservices architectures are two distinct technologies with different approaches to solving problems. The most significant difference between the two is that microservices can run 24/7, offering long-term solutions, while a serverless model only starts running when there is a specific input, meaning it prioritizes code efficiency.
But let’s take a closer look at the differences and similarities between these two architectures so you can decide which approach is best suited to your business needs.
What Is a Serverless Model?
Serverless architecture is a way to build and run apps and services on cloud infrastructure that is managed by a third-party provider. Because the cloud provider takes care of servers – scaling, availability, and security – a serverless model allows developers to fully focus on writing application code. By offloading hardware software maintenance, security updates, software updates, backup creations, etc., to a third-party provider, developers only need to worry about writing code – that’s it.
A serverless model is also very cost-efficient as developers or companies pay only for those resources that their code consumes, but not for idle server capacity. Also, since a third-party provider takes care of servers, there’s no need to hire server and hardware specialists, saving on HR expenses.
Using this model, application code is executed on-demand, meaning only when there is a specific input that developers configure ahead of time. For instance, an authentication service would be a great candidate for serverless architecture as it’s not required 24/7 but only occasionally.
What Are Microservices?
Microservices architecture is a decentralized approach to building an app in which parts of the app are broken down into a series of small (or micro) services. Each part is independently deployable, and they all communicate with each other via application programming interfaces (APIs). Also, each microservice is designed to do one task well and can be scaled and updated independently of the other services.
This approach allows developers to build complex applications that are easier to maintain and scale. It is the opposite of the monolithic approach, where applications are built and deployed as one holistic unit.
Developing microservices is more expensive in the beginning as you need multiple teams to handle the project. Additionally, its maintenance is more costly as it doesn’t rely on third-party resources and support. On the plus side, the company doesn’t depend on third-party plans.
Microservices can run constantly, and since they’re not limited by the provider’s requirements to runtime and storage space, they’re ideal for complex long-term operations.
Combining Serverless and Microservices
While serverless and microservices are different types of technologies, they are closely related. In fact, you don’t have to choose between the two architectures anymore – you can combine them
Since serverless architecture is event or input-triggered, microservices must be event or input-triggered, too, to be serverless. In other words, to create a serverless microservice, you need to write the code for a microservice and then set it up to run as a serverless function.
So what microservices are good candidates for this model? Pretty much any that need to run occasionally. For instance, messaging queues and read receipts are two examples of features that can be implemented using a combination of serverless and microservices architectures.
Message Queues & Delivery Receipts with Serverless Microservices
Serverless microservices provide an ideal platform for implementing message queues and delivery receipts.
First things first, what are delivery receipts? Put simply, delivery receipts tell the sender of the message that the message was delivered to the recipient’s device or email address. Let’s take Android chat apps as an example. This is how a messaging lifecycle would go without a delivery receipt:
- You send the message.
- The message goes to the server.
- A recipient reads the message.
Simple, right? Yes, in fact, too simple. Without a delivery receipt, a sender has no idea if the message was successfully received by the recipient, leaving them to wonder if they saw no response due to poor connection or if the recipient didn’t have time to check their messages yet.
With a delivery receipt, another step in the messaging lifecycle happens right before the last one: the message is delivered to the recipient’s device. By implementing delivery receipts in Android, developers have more flexibility on what they choose to do once the message has been delivered.
So, broadly speaking, the benefits of serverless microservices architecture include scalability, cost-effectiveness, real-time processing, and the ability to track the delivery status of messages in the message queue and delivery receipts scenario.
There’s no doubt that serverless microservices provide multiple benefits. Aside from the obvious ones – less overhead cost, improved efficiency, and scalability – the biggest plus is how easy it is to combine serverless functions with other managed services. You can integrate functions with message queues, databases, and API management tools in similar ways for various purposes. This way, resources and functions used in one microservice can be used as a base for other microservices.