Getting started with Azure serverless.

Serverless deployment has become a popular option in many cloud environments. Each cloud provider has several services that encapsulate their serverless offerings, and Microsoft Azure is no different.

This blog covers several primary serverless services, including Azure Functions, Azure Logic Apps, Azure Event Grid, Azure Event Hubs, Azure Container Apps, and Azure Cosmos DB.

Additionally, it discusses various architectural frameworks and use cases, such as order processing and event-driven solutions.

The blog will also highlight best practices for deploying Azure serverless applications, as well as the tools that facilitate deployment, including cost optimization techniques for each service.

Let's get started unpacking.

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Introduction to Azure Serverless Computing

What is Serverless Architecture?

The term "serverless" does not imply the complete elimination of servers; instead, it refers to a model that enables developers to focus primarily on coding, rather than managing the underlying infrastructure required for code execution. Within this framework of serverless applications, the cloud service provider assumes the responsibility for the automatic provisioning, scaling, and management of the necessary infrastructure to ensure effective code execution.

The term "Serverless" encompasses two distinct meanings: Backend as a Service (BaaS) and Functions as a Service (FaaS). However, both concepts share the underlying principle that developers and DevOps engineers are not required to deploy, configure, or manage servers.

• BaaS refers to cloud services that provide backend functionalities, including databases and storage. These services provide APIs that allow source applications to connect directly to them.
• FaaS is a model where a function is a piece of code that executes within the cloud provider's hosting environment. This model abstracts away the underlying code and servers that run the Function.

The diagram below illustrates the Azure architecture of an application designed to serve static content using Azure Blob Storage while also integrating an API through Azure Functions. This API retrieves data from Azure Cosmos DB and returns the results to the web application.

This example demonstrates the two meanings of BaaS and FaaS within Azure. Specifically, it refers to FaaS through Azure Functions, while Azure Blob Storage serves as an example of BaaS.

There are characteristics within serverless that have advantages and disadvantages. The advantages include:

• Cost — Only pay for the resources you use, avoiding charges for idle resources like web or middleware servers, and reduce waste during off-peak hours. If you know your access patterns, you can save even more by purchasing reserved capacity.
• Less Maintenance — Since the cloud provider manages the underlying server management complexities, developers are free to focus on building the application and features.
• Scalable — Serverless components can automatically scale for handling unpredictable or up-and-down traffic patterns.
• Support — A large support community exists, and most cloud providers offer services that either integrate with or utilize serverless components.

Some of the disadvantages of serverless computing:

• Performance — Performance issues can emerge in various aspects of a decoupled serverless architecture, making it difficult to pinpoint which API or component is responsible for the slowdown. Moreover, if a function has not been utilized for some time, it may encounter a cold start. A cold start occurs because the service provider must allocate resources for the Function to execute, which can require extra time, resulting in performance slowness for the application.
• Vendor lock-in — Typically, serverless services are provided by the vendor, which can make migration off the platform challenging and costly.
• Limited control — a customer may face limitations in their actions because they lack control over the underlying infrastructure. If the application depends on specific environmental configurations, it may not function properly with serverless. Additionally, there are often restrictions on runtime execution, the maximum number of functions, and the programming languages supported.
• Security — Since the provider is responsible for the underlying operating system and infrastructure of the serverless service, security largely depends on the measures they implement. This situation can potentially create vulnerabilities, as each Function may act as an attack vector.

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Why Choose Azure for Serverless?

While many public cloud providers offer serverless architecture frameworks, Azure stands out for several reasons:

• Support for a Wider Range of Languages: Azure accommodates a diverse set of programming languages, allowing developers to work in their preferred environments.
• Local Debugging Capabilities: With tools like Visual Studio, Azure provides features that enhance developer productivity by facilitating local debugging.
• Comprehensive Ecosystem: Azure enables the creation of complete serverless solutions for both front-end and backend applications, with services that work together effectively and efficiently. Azure enables developers to create innovative apps that easily integrate code for machine learning and AI services.

These advantages make Azure a compelling choice for serverless architecture.

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Popular Azure Serverless Services

Azure Functions

Azure Functions serve as the backend logic in serverless applications, constituting the foundation of Function as a Service (FaaS). They offer scalability and support an event-driven architecture. Furthermore, functions can call external services, such as third-party payment processors, to complete transactions.

They include a comprehensive array of event-driven triggers and bindings that connect the functions to other services effortlessly, removing the necessity for additional code.

The following summary is the purpose and some of the use cases for using Azure Functions:

Azure Functions support a variety of languages, making it a compelling resource for serverless computing. The languages that are supported include the following:

Azure Durable Functions expands the capabilities of Azure Functions, allowing you to create stateful workflows and coordination logic through an orchestrator pattern. This extension aids in developing long-running, scalable, and dependable serverless applications.

Cost Optimization Techniques:

• Choose the Consumption Plan for event-driven workloads. Learn more.
• Optimize memory allocation to reduce GB-seconds billing. Best practices.
• Use Durable Functions wisely to avoid excessive executions. Read about Durable Functions.
• Azure Functions Premium Plan: Use for predictable high-performance workloads. Understand Premium Plan costs.

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Azure Logic Apps

Azure Logic Apps provides a robust serverless orchestration solution specifically designed for developing and managing complex workloads. As Microsoft's cloud-based integration platform as a service (iPaaS), it enables seamless automation of workflows that connect a wide range of services and applications.

This powerful tool streamlines the integration process, enabling organizations to enhance operational efficiency, reduce manual interventions, and respond more quickly to evolving business needs.

By utilizing predefined templates and connectors, users can quickly establish sophisticated workflows that integrate disparate systems, fostering innovation and boosting overall productivity.

Here are some key characteristics of Azure Logic Apps that make it worth considering for workflow orchestration:

• Visual designer for creating automated business processes or workflows
• 1,400+ prebuilt connectors with triggers and actions
• Low-Code/No-Code Approach
• Hosted by Microsoft Azure, which is responsible for hosting, scaling, managing, monitoring, and maintaining solutions built with these services.

Mixing and matching services is quite common in Serverless computing. For example, you can call functions from Logic App workflows and call Logic App workflows from functions. The following table lists some key differences between Azure Functions and Azure Logic Apps.

Cost Optimization Techniques:

• Select the Standard Plan for predictable pricing. Compare pricing models.
• Optimize workflow design to minimize unnecessary actions. Logic Apps design patterns.
• Implement batch processing to reduce per-action costs. Processing strategies.
• Azure Logic Apps Custom Connectors: Reduce API call frequency to lower execution costs. Best practices.

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Azure Event Grid

Azure Event Grid is a service designed to streamline the development of event-driven applications by routing events from various Azure services and custom sources to subscribers, such as Azure Functions, Logic Apps, webhooks, or any HTTP endpoint.

This service, characterized by its scalability and comprehensive management, operates under the publish/subscribe (Pub/Sub) model and supports both MQTT v3.1.1 and v5.0 protocols, as well as HTTP, facilitating the creation of data pipelines, application integrations, and event-driven serverless architectures. Furthermore, it possesses the capability to publish and subscribe to messages for Internet of Things (IoT) solutions, accommodating both push and pull event delivery methods.

Additionally, Event Grid complies with the CloudEvents 1.0 specification, thereby enhancing interoperability across various systems.

Below is a general diagram of the Azure Event Grid.

The two core features of Azure Event Grid are:

• MQTT messaging enables IoT devices and applications to communicate with each other via MQTT. Event Grid can leverage MQTT to direct messages to Azure services or custom endpoints for additional analysis, visualization, or storage.

• Data Distributed using push and pull delivery modes — At any point in the data pipeline, HTTP applications can consume messages using push or pull API's

Cost Optimization Techniques:

• Use Basic Tier for lower-cost event routing. View pricing.
• Filter events before they reach subscribers to reduce processing overhead. Event filtering guide.
• Monitor event delivery attempts to avoid excessive retries. Reliability best practices.

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Azure Event Hubs

Azure Event Hubs is a fully managed, real-time data ingestion service that offers simplicity, security, and scalability. It provides support for popular protocols including AMQP, HTTPS, and Apache Kafka. The service can ingest millions of events per second.

The capability to ingest millions of events per second and analyze data in real time is particularly beneficial for applications that require immediate insights and responsiveness to changing data patterns, making it an essential component in modern cloud-based architectures.

The integration into other Azure services happens seamlessly, and you can gain valuable insights into the data, and also microbatching on the same stream.

Azure Event Hubs enables the creation of a comprehensive, serverless streaming solution that seamlessly integrates with Stream Analytics.

Some of the use cases provided by Azure documentation include:

• Process data from your event hub by using Azure Stream Analytics to generate real-time insights.
• Analyze and explore streaming data with Azure Data Explorer.
• Create your own cloud native applications, functions, or microservices that run on streaming data from Event Hubs.
• Stream events with schema validation by using the built-in Azure Schema Registry to ensure quality and compatibility of streaming data.