Azure Compute App Services

Comprehensive documentation for building and deploying web applications on Azure.

App Service Overview

Azure App Service is a fully managed platform for building, deploying, and scaling web apps, mobile back ends, and APIs. It's designed to be flexible and powerful, offering a variety of hosting plans and features to support diverse application needs.

Key Features

  • Platform as a Service (PaaS): Focus on development, not infrastructure management.
  • Support for Multiple Languages and Frameworks: .NET, .NET Core, Java, Ruby, Node.js, PHP, Python, and custom containers.
  • Automated Deployments: Integrate with Azure DevOps, GitHub, Bitbucket, and other CI/CD tools.
  • Scalability: Easily scale your applications up or out based on demand.
  • Global Reach: Deploy your apps to Azure datacenters around the world.
  • Built-in Security: SSL certificates, IP restrictions, authentication, and authorization.
  • Monitoring and Diagnostics: Application Insights, Log Analytics, and built-in diagnostics.

Hosting Plans

App Service offers several hosting plans tailored to different needs:

  • Free/Shared: For development, testing, and small production workloads.
  • Basic: For production apps that need custom domains and SSL.
  • Standard: For production apps that require automated backups, staging slots, and advanced features.
  • Premium: For mission-critical apps needing enhanced performance, VNet integration, and more powerful hardware.
  • Isolated: For dedicated environments with enhanced security and network isolation.

Important Note

Choosing the right App Service plan is crucial for performance, cost, and feature availability. Review the Pricing Tiers section for detailed comparisons.

Getting Started with App Service

Follow these steps to get your first web application running on Azure App Service:

  1. Create an Azure Account: If you don't have one, sign up for a free trial.
  2. Choose a Development Framework: Select your preferred language and framework (e.g., ASP.NET Core, Node.js).
  3. Develop Your Application: Build and test your application locally.
  4. Deploy to App Service: Use Azure CLI, Azure Portal, Visual Studio, or CI/CD pipelines.

Creating an App Service

You can create an App Service instance through the Azure Portal, Azure CLI, or Azure PowerShell.

Using the Azure Portal:
  1. Navigate to the Azure Portal.
  2. Click Create a resource.
  3. Search for "Web App" and select it.
  4. Configure the Subscription, Resource Group, App Name, Runtime Stack, and Operating System.
  5. Choose your desired Hosting Plan.
  6. Click Review + create, then Create.
Using Azure CLI:
az group create --name MyResourceGroup --location "East US" az appservice plan create --name MyServicePlan --resource-group MyResourceGroup --sku S1 --is-linux az webapp create --resource-group MyResourceGroup --plan MyServicePlan --name MyAwesomeApp --functions-version 4

Deployment Options

App Service supports a variety of deployment methods:

  • CI/CD Integration: GitHub Actions, Azure DevOps, Bitbucket Pipelines for automated builds and deployments.
  • Local Git Deployment: Deploy directly from a local Git repository.
  • FTP/FTPS: Deploy files via FTP or FTPS.
  • Web Deploy: Use the Web Deploy tool for Windows-based App Services.
  • Container Registry: Deploy applications packaged as Docker containers.
  • Azure Repositories: Connect directly to Azure Repos Git repositories.

Deployment Slots

Use deployment slots for staging and testing new versions of your app before swapping them into production. This minimizes downtime and risk.

Configuration and Settings

App Service provides extensive configuration options:

  • Application Settings: Environment variables for your application.
  • Connection Strings: Database connection details.
  • General Settings: Runtime version, platform, Always On, etc.
  • Authentication and Authorization: Integrate with identity providers like Azure AD, Google, Facebook.
  • Custom Domains and SSL: Map custom domains and secure them with SSL certificates.
  • Path Mappings: Map different URL paths to specific content or applications.

Scaling and Performance

Scale your application to handle fluctuating traffic:

  • Manual Scaling: Adjust the instance count or performance tier manually.
  • Autoscaling: Configure rules based on metrics like CPU usage, memory, or HTTP queue length to automatically scale instances up or down.
  • Always On: Keep your application loaded and ready to respond to requests, preventing cold starts (available in Standard tier and above).
  • Caching: Implement caching strategies at the application level or using services like Azure Cache for Redis.

Monitoring and Diagnostics

Gain insights into your application's health and performance:

  • Application Insights: APM service for detailed performance monitoring, exception tracking, and dependency analysis.
  • Log Streaming: Real-time access to application logs.
  • Diagnostics Logs: Configure logging for App Service itself (e.g., web server logs, deployment logs).
  • Kudu Console: Advanced diagnostic tools, file access, and process management.

Security Best Practices

  • Use Managed Identities to securely access other Azure resources.
  • Implement authentication and authorization using Azure AD or other providers.
  • Secure your custom domains with SSL/TLS certificates.
  • Configure IP restrictions to limit access to specific IP addresses or ranges.
  • Keep your application dependencies and runtime updated.
  • Review and secure application settings and connection strings.

Custom Domains and SSL

Map your own domain names (e.g., www.yourcompany.com) to your App Service. You can upload your own SSL certificates or use Azure-provided certificates.

API Management Integration

Easily integrate your App Service APIs with Azure API Management to manage, secure, and publish your APIs to consumers.

Pricing Tiers

App Service pricing varies based on the selected tier and the number of instances. Key differences include:

  • Free/Shared: Limited features, shared infrastructure.
  • Basic: Custom domains, SSL, staging slots.
  • Standard: Daily backups, autoscaling, custom SSL certificates, VNet integration (later tiers).
  • Premium: Enhanced performance, VNet integration, Hybrid Connections, Deployment Slots.
  • Isolated: Dedicated Azure Virtual Network, full control.

Refer to the official Azure App Service pricing page for the most up-to-date information.