API Apps
This section provides comprehensive documentation for developing and managing API Apps within Azure App Service.
Table of Contents
What are API Apps?
API Apps are a specialized type of Azure App Service designed specifically for hosting, discovering, and managing your APIs. They provide a robust platform for building RESTful APIs, SOAP services, and other web services that can be consumed by various applications, from mobile apps to enterprise systems.
API Apps streamline the development lifecycle by offering built-in features for:
- API Definition: Support for OpenAPI (Swagger) and WSDL.
- Discoverability: Easy integration with API marketplaces and catalogs.
- Security: Built-in authentication and authorization mechanisms.
- Lifecycle Management: Versioning, staging, and deployment.
Key Features
- Language and Framework Agnostic: Deploy APIs written in any language or framework.
- Scalability: Automatically scale your APIs based on demand.
- DevOps Integration: Seamless integration with CI/CD pipelines.
- Custom Domains and SSL: Secure your APIs with custom domains and SSL certificates.
- Azure Functions Integration: Combine the power of API Apps with serverless Azure Functions.
Getting Started
To start building your API App, you'll typically follow these steps:
- Create an API App: Use the Azure portal, Azure CLI, or ARM templates to create a new API App resource.
- Develop Your API: Write your API logic using your preferred programming language and framework.
- Define Your API: Generate or create an OpenAPI (Swagger) or WSDL definition for your API.
- Deploy Your API: Deploy your API code to the API App using deployment slots or CI/CD pipelines.
- Configure Security: Set up authentication and authorization using Azure Active Directory or other identity providers.
API Definitions
API Apps leverage standard API definition formats to describe your API's capabilities. The most common formats are:
- OpenAPI (Swagger): A standard, language-agnostic interface description for RESTful APIs. It allows both humans and computers to understand the structure of your REST APIs without needing to access the source code, documentation, or network traffic inspecting.
- WSDL (Web Services Description Language): Used for SOAP-based web services.
API Apps can automatically generate an OpenAPI definition if you use certain frameworks (e.g., ASP.NET Core with Swashbuckle). You can also upload a custom definition.
Managing Definitions
Once deployed, you can access your API definition from the Azure portal under the "API definition" blade of your API App. This allows you to explore endpoints, request/response formats, and parameters.
Security
Securing your APIs is paramount. API Apps offer several security features:
- Authentication: Verify the identity of the caller.
- Azure Active Directory (Azure AD)
- OAuth 2.0
- API Keys
- Authorization: Control what authenticated callers can do.
- TLS/SSL: Enforce secure communication channels.
Azure AD Integration
Integrating with Azure AD provides robust identity management and single sign-on capabilities for your APIs.
To configure Azure AD authentication:
- Register your API App in Azure AD.
- Configure the API App in the Azure portal to use Azure AD as an identity provider.
- Update your client applications to authenticate with Azure AD and include the necessary tokens in their requests.
Managing API Apps
The Azure portal provides a comprehensive interface for managing your API Apps. Key management tasks include:
- Deployment Slots: Deploy new versions of your API to a staging slot before swapping to production, minimizing downtime.
- Scaling: Adjust the instance count and tier to meet performance requirements.
- Monitoring: Track performance metrics, logs, and diagnose issues.
- Access Control (IAM): Manage permissions for users and services accessing your API App.
Tutorials
Explore these tutorials to learn more: