Azure API Management vs Azure Functions: What are the differences?

Azure API Management vs Azure Functions

Azure API Management and Azure Functions are both services offered by Microsoft Azure for building and managing cloud applications. However, they serve different purposes and have distinctive features. Here are the key differences between Azure API Management and Azure Functions:

1. Scalability and Execution Mode: Azure API Management is designed for managing and exposing APIs to external developers and consumers. It acts as a gateway and enables centralized control and monitoring of APIs. On the other hand, Azure Functions is a serverless compute service that allows developers to run event-driven functions in the cloud. It provides automatic scaling and executes functions in a pay-as-you-go manner.

2. Primary Use Case: Azure API Management is commonly used for creating public or private APIs, implementing rate limiting, authentication, and versioning for APIs, and managing developer portals. It provides the necessary tools for API governance and monetization. In contrast, Azure Functions is mainly used for building serverless applications and executing event-triggered functions. It is ideal for scenarios like data processing, task automation, and event-driven architectures.

3. Developer Experience: Azure API Management provides a comprehensive and user-friendly developer portal that allows API consumers to easily discover, explore, and test APIs. It also offers features like interactive documentation, code samples, and subscription management. Azure Functions, on the other hand, provides a simplified development experience with a wide range of supported programming languages and integrated development tools.

4. Execution Model: Azure API Management operates in a stateful manner, maintaining the API state and retaining request/response information. It provides advanced features like caching, traffic management, and error handling. Azure Functions, on the other hand, follows a stateless execution model. Each function is invoked independently and does not maintain any state between invocations. It allows easy scaling and decoupling of individual functions.

5. Pricing Model: Azure API Management pricing is based on the number of API calls, additional features, and the number of developer portals. It provides flexible pricing tiers and options for customization. Azure Functions pricing is based on the number of executions and the duration of each execution. It offers a consumption plan where you pay only for the resources consumed during function execution.

6. Integration Capabilities: Azure API Management provides seamless integration with other Azure services and offers various integration policies for transforming, enriching, and securing API requests and responses. It integrates with Azure Logic Apps, Service Bus, and Azure Active Directory, among others. Azure Functions also integrates well with Azure services and provides built-in bindings for working with Azure Storage, Cosmos DB, Event Hubs, and more. It enables easy integration of functions with other Azure resources.

In summary, Azure API Management is focused on managing and exposing APIs, providing governance and monetization features, while Azure Functions is a serverless compute service for executing event-driven functions, enabling rapid development of cloud applications.