Azure Functions Language Support
Azure Functions supports a variety of programming languages, allowing you to use the language you are most comfortable with to build your serverless applications. The runtime provides an execution environment and APIs for each supported language.
Supported Languages
The following languages are officially supported by Azure Functions:
- C#: A first-class citizen, with excellent tooling and integration. Supports .NET Core and .NET Framework.
- JavaScript: Native support for Node.js, enabling easy development of event-driven applications.
- TypeScript: Offers static typing and modern JavaScript features, compiling down to JavaScript.
- Java: Robust support for enterprise development with the Java ecosystem.
- Python: Widely adopted for its ease of use and extensive libraries, ideal for data science and scripting.
- PowerShell: Excellent for automation tasks and integrating with Azure services.
- TypeScript: Leverages static typing and modern JavaScript features for enhanced developer experience.
Language Worker Model
Azure Functions uses a language worker model. The runtime hosts a language-specific worker process. This worker process is responsible for:
- Loading your function code.
- Handling function invocations.
- Managing triggers and bindings.
- Communicating execution results back to the Functions runtime.
This model allows for language flexibility and independent updates of language runtimes and workers without requiring changes to the core Functions runtime.
Choosing a Language
The choice of language often depends on your team's expertise, existing codebases, and the specific requirements of your project. Consider the following:
- Development Speed: Languages like Python and JavaScript often offer faster development cycles for certain types of applications.
- Performance: For CPU-intensive tasks, compiled languages like C# or Java might offer better performance.
- Ecosystem & Libraries: Leverage the vast libraries available in languages like Python (e.g., for machine learning, data analysis) or Node.js (for web-related tasks).
- Tooling & IDE Support: Ensure your preferred development environment offers robust tooling for the chosen language. Azure provides excellent tooling for C#, JavaScript, TypeScript, and Python through Visual Studio Code and Visual Studio.
Language-Specific Considerations
C#
C# offers deep integration with the Azure ecosystem. You can develop functions using:
- In-process model: For .NET Core 3.0+ functions, offering better performance.
- Out-of-process model: Compatible with older .NET versions and .NET Framework.
Example C# function signature:
public static void Run(TimerInfo myTimer, ILogger log)
{
    log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");
}JavaScript/TypeScript
Ideal for web developers and event-driven architectures. Node.js functions are easy to get started with.
Example JavaScript function:
module.exports = async function (context, req) {
    context.log('JavaScript HTTP trigger function processed a request.');
    const name = (req.query.name || (req.body && req.body.name));
    const responseMessage = name
        ? "Hello, " + name + "!"
        : "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response.";
    context.res = {
        body: responseMessage
    };
};Python
Python functions are perfect for scripting, data processing, and integrating with AI/ML services.
Example Python function:
import logging
import azure.functions as func
def main(req: func.HttpRequest) -> func.HttpResponse:
    logging.info('Python HTTP trigger function processed a request.')
    name = req.params.get('name')
    if not name:
        try:
            req_body = req.get_json()
        except ValueError:
            pass
        else:
            name = req_body.get('name')
    if name:
        return func.HttpResponse(f"Hello, {name}!")
    else:
        return func.HttpResponse(
             "This HTTP triggered function executed successfully. Pass a name in the query string or in the request body for a personalized response.",
             status_code=200
        )Java
Leverage the power of the Java Virtual Machine (JVM) for your serverless applications.
Example Java function (simplified):
public class Function {
    public static void run(String name, org.slf4j.Logger logger) {
        logger.info("Java HTTP trigger processed a request.");
        if (name != null && name.trim().length() != 0) {
            logger.info("Hello, " + name);
        } else {
            logger.info("Please pass a name on the query string or in the request body for a personalized response.");
        }
    }
}Important Note
While Azure Functions supports multiple languages, it's crucial to use the correct versions of the language runtime and SDKs as specified in the Azure Functions documentation for the best compatibility and performance.
Pro Tip
Consider using Azure Functions Core Tools for local development and testing. It provides a seamless experience for building and debugging functions in your chosen language before deploying to Azure.
Deployment
Deployment methods vary by language. You can deploy using:
- Azure CLI
- Azure Portal
- Visual Studio Code extensions
- Visual Studio
- Azure DevOps, GitHub Actions, and other CI/CD pipelines
Community Support
Engage with the Azure Functions community on forums, Stack Overflow, and GitHub to share knowledge, ask questions, and find solutions.