Azure Functions FAQ

Azure Functions is a serverless compute service that enables you to run code on-demand without explicitly provisioning or managing infrastructure. It's event-driven and allows you to build applications using small pieces of code, called functions, that are triggered by various events.

• Cost-effective: You pay only for the time your code runs.
• Scalable: Automatically scales based on demand.
• Event-driven: Integrates with a wide range of Azure services and external event sources.
• Simplified development: Focus on writing code, not managing servers.
• Polyglot support: Supports multiple programming languages like C#, JavaScript, Python, PowerShell, Java, and more.

Triggers define how a function is invoked. For example, an HTTP trigger starts a function when a web request is received, a timer trigger starts a function on a schedule, and a queue trigger starts a function when a message is added to a storage queue.

Bindings connect your function to other services. They simplify the code needed to interact with data and services. For instance, an input binding can read data from a database, and an output binding can write data to a storage account.

Azure Functions supports a variety of languages, including:

• C#
• JavaScript
• TypeScript
• Python
• PowerShell
• Java
• node.js

Azure Functions offers three main hosting plans:

• Consumption Plan: Pay-per-execution model with automatic scaling. Ideal for event-driven workloads.
• Premium Plan: Provides pre-warmed instances, VNet connectivity, and no cold starts, offering enhanced performance and reliability.
• Dedicated (App Service) Plan: Run functions on the same infrastructure as your App Service apps, offering predictable costs and performance.

Dependencies are managed using the package manager specific to your chosen language. For example:

• Node.js: Use npm or yarn with a package.json file.
• Python: Use pip with a requirements.txt file.
• .NET: Use NuGet package manager.

Ensure these dependency files are included in your deployment package.

A "cold start" occurs when your function app hasn't been active for a while, and the underlying infrastructure needs to be initialized before your function can execute. This can introduce a delay in the first request. The Premium and Dedicated plans help mitigate cold starts by keeping instances warm.

Azure Functions integrates with Azure Monitor and Application Insights. You can view logs, track execution times, monitor performance metrics, and set up alerts to gain insights into your function's behavior and identify potential issues.