Azure Functions HTTP trigger

The Python v2 programming model lets you define bindings using decorators directly in your Python function code. For more information, see the Python developer guide.

The Python v1 programming model requires you to define bindings in a separate function.json file in the function folder. For more information, see the Python developer guide.

The following example shows an HTTP trigger that returns a "hello, world" response as an IActionResult, using ASP.NET Core integration in .NET Isolated:

[Function("HttpFunction")]
public IActionResult Run(
    [HttpTrigger(AuthorizationLevel.Anonymous, "get")] HttpRequest req)
{
    return new OkObjectResult($"Welcome to Azure Functions, {req.Query["name"]}!");
}

The following example shows an HTTP trigger that returns a "hello world" response as an HttpResponseData object:

// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the MIT License. See License.txt in the project root for license information.

using System.Net;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;

namespace SampleApp
{
    public static class HttpFunction
    {
        //<docsnippet_http_trigger>
        [Function(nameof(HttpFunction))]
        public static HttpResponseData Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequestData req,
            FunctionContext executionContext)
        {
            //<docsnippet_logging>
            var logger = executionContext.GetLogger(nameof(HttpFunction));
            logger.LogInformation("message logged");
            //</docsnippet_logging>

            var response = req.CreateResponse(HttpStatusCode.OK);
            response.Headers.Add("Content-Type", "text/plain; charset=utf-8");
            response.WriteString("Welcome to .NET isolated worker !!");

            return response;
        }
        //</docsnippet_http_trigger>
    }
}

The following example shows a C# function that looks for a name parameter either in the query string or the body of the HTTP request. Notice that the return value is used for the output binding, but a return value attribute isn't required.

[FunctionName("HttpTriggerCSharp")]
public static async Task<IActionResult> Run(
    [HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)]
    HttpRequest req, ILogger log)
{
    log.LogInformation("C# HTTP trigger function processed a request.");

    string name = req.Query["name"];

    string requestBody = String.Empty;
    using (StreamReader streamReader =  new  StreamReader(req.Body))
    {
        requestBody = await streamReader.ReadToEndAsync();
    }
    dynamic data = JsonConvert.DeserializeObject(requestBody);
    name = name ?? data?.name;

    return name != null
        ? (ActionResult)new OkObjectResult($"Hello, {name}")
        : new BadRequestObjectResult("Please pass a name on the query string or in the request body");
}

The following example shows an HTTP trigger TypeScript function. The function looks for a name parameter either in the query string or the body of the HTTP request.

import { app, HttpRequest, HttpResponseInit, InvocationContext } from '@azure/functions';

export async function httpTrigger1(request: HttpRequest, context: InvocationContext): Promise<HttpResponseInit> {
    context.log(`Http function processed request for url "${request.url}"`);

    const name = request.query.get('name') || (await request.text()) || 'world';

    return { body: `Hello, ${name}!` };
}

app.http('httpTrigger1', {
    methods: ['GET', 'POST'],
    authLevel: 'anonymous',
    handler: httpTrigger1,
});

TypeScript samples aren't documented for model v3.

The following example shows an HTTP trigger JavaScript function. The function looks for a name parameter either in the query string or the body of the HTTP request.

const { app } = require('@azure/functions');

app.http('httpTrigger1', {
    methods: ['GET', 'POST'],
    authLevel: 'anonymous',
    handler: async (request, context) => {
        context.log(`Http function processed request for url "${request.url}"`);

        const name = request.query.get('name') || (await request.text()) || 'world';

        return { body: `Hello, ${name}!` };
    },
});

The following example shows a trigger binding in a function.json file and a JavaScript function that uses the binding. The function looks for a name parameter either in the query string or the body of the HTTP request.

Here's the function.json file:

{
    "disabled": false,    
    "bindings": [
        {
            "authLevel": "function",
            "type": "httpTrigger",
            "direction": "in",
            "name": "req"
        },
        {
            "type": "http",
            "direction": "out",
            "name": "res"
        }
    ]
}

The configuration section explains these properties.

Here's the JavaScript code:

module.exports = async function(context, req) {
    context.log('Node.js HTTP trigger function processed a request. RequestUri=%s', req.originalUrl);

    if (req.query.name || (req.body && req.body.name)) {
        context.res = {
            // status defaults to 200 */
            body: "Hello " + (req.query.name || req.body.name)
        };
    }
    else {
        context.res = {
            status: 400,
            body: "Please pass a name on the query string or in the request body"
        };
    }
};

This example uses HTTP streams to return chunked response data.

import time

import azure.functions as func
from azurefunctions.extensions.http.fastapi import Request, StreamingResponse

app = func.FunctionApp(http_auth_level=func.AuthLevel.ANONYMOUS)


def generate_sensor_data():
    """Generate real-time sensor data."""
    for i in range(10):
        # Simulate temperature and humidity readings
        temperature = 20 + i
        humidity = 50 + i
        yield f"data: {{'temperature': {temperature}, 'humidity': {humidity}}}\n\n"
        time.sleep(1)


@app.route(route="stream", methods=[func.HttpMethod.GET])
async def stream_sensor_data(req: Request) -> StreamingResponse:
    """Endpoint to stream real-time sensor data."""
    return StreamingResponse(generate_sensor_data(), media_type="text/event-stream")

To learn more, including how to enable HTTP streams in your project, see HTTP streams.

This example shows a trigger binding and a Python function that uses the binding. The function looks for a name parameter either in the query string or the body of the HTTP request.

import azure.functions as func
import logging

app = func.FunctionApp()

@app.function_name(name="HttpTrigger1")
@app.route(route="hello", auth_level=func.AuthLevel.ANONYMOUS)
def test_function(req: func.HttpRequest) -> func.HttpResponse:
    logging.info('Python HTTP trigger function processed a request.')
    return func.HttpResponse(
        "This HTTP triggered function executed successfully.",
        status_code=200
        )

This example shows a trigger binding and a Python function that uses the binding. The function looks for a name parameter either in the query string or the body of the HTTP request.

Here's the function.json file:

{
    "scriptFile": "__init__.py",
    "disabled": false,    
    "bindings": [
        {
            "authLevel": "function",
            "type": "httpTrigger",
            "direction": "in",
            "name": "req"
        },
        {
            "type": "http",
            "direction": "out",
            "name": "$return"
        }
    ]
}

The configuration section explains these properties.

Here's the Python code:

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(
            "Please pass a name on the query string or in the request body",
            status_code=400
        )

In isolated worker model function apps, the HttpTriggerAttribute supports the following parameters:

In in-process functions, the HttpTriggerAttribute supports the following parameters:

The following table explains the properties that you can set on the options object passed to the app.http() method.

The following table explains the binding configuration properties that you set in the function.json file.

The following table explains the binding configuration properties that you set in the function.json file.

The following table explains the binding configuration properties that you set in the function.json file.

The trigger input type is declared as one of the following types:

When the trigger parameter is of type HttpRequestData or HttpRequest, custom types can also be bound to other parameters using Microsoft.Azure.Functions.Worker.Http.FromBodyAttribute. Use of this attribute requires Microsoft.Azure.Functions.Worker.Extensions.Http version 3.1.0 or later. This is a different type than the similar attribute in Microsoft.AspNetCore.Mvc. When using ASP.NET Core integration, you need a fully qualified reference or using statement. This example shows how to use the attribute to get just the body contents while still having access to the full HttpRequest, using ASP.NET Core integration:

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.Functions.Worker;
using FromBodyAttribute = Microsoft.Azure.Functions.Worker.Http.FromBodyAttribute;

namespace AspNetIntegration
{
    public class BodyBindingHttpTrigger
    {
        [Function(nameof(BodyBindingHttpTrigger))]
        public IActionResult Run([HttpTrigger(AuthorizationLevel.Anonymous, "post")] HttpRequest req,
            [FromBody] Person person)
        {
            return new OkObjectResult(person);
        }
    }

    public record Person(string Name, int Age);
}

The trigger input type is declared as either HttpRequest or a custom type. If you choose HttpRequest, you get full access to the request object. For a custom type, the runtime tries to parse the JSON request body to set the object properties.

The following function code accepts two parameters category and id in the route and writes a response using both parameters.

[Function("HttpTrigger1")]
public static HttpResponseData Run([HttpTrigger(AuthorizationLevel.Function, "get", "post",
Route = "products/{category:alpha}/{id:int?}")] HttpRequestData req, string category, int? id,
FunctionContext executionContext)
{
    var logger = executionContext.GetLogger("HttpTrigger1");
    logger.LogInformation("C# HTTP trigger function processed a request.");

    var message = String.Format($"Category: {category}, ID: {id}");
    var response = req.CreateResponse(HttpStatusCode.OK);
    response.Headers.Add("Content-Type", "text/plain; charset=utf-8");
    response.WriteString(message);

    return response;
}

The following C# function code accepts two parameters category and id in the route and writes a response using both parameters.

[FunctionName("Function1")]
public static IActionResult Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = "products/{category:alpha}/{id:int?}")] HttpRequest req,
string category, int? id, ILogger log)
{
    log.LogInformation("C# HTTP trigger function processed a request.");

    var message = String.Format($"Category: {category}, ID: {id}");
    return (ActionResult)new OkObjectResult(message);
}

As an example, the following TypeScript code defines a route property for an HTTP trigger with two parameters, category and id. The example reads the parameters from the request and returns their values in the response.

import { app, HttpRequest, HttpResponseInit, InvocationContext } from '@azure/functions';

export async function httpTrigger1(request: HttpRequest, context: InvocationContext): Promise<HttpResponseInit> {
    const category = request.params.category;
    const id = request.params.id;

    return { body: `Category: ${category}, ID: ${id}` };
}

app.http('httpTrigger1', {
    methods: ['GET'],
    authLevel: 'anonymous',
    route: 'products/{category:alpha}/{id:int?}',
    handler: httpTrigger1,
});

TypeScript samples aren't documented for model v3.

As an example, the following JavaScript code defines a route property for an HTTP trigger with two parameters, category and id. The example reads the parameters from the request and returns their values in the response.

const { app } = require('@azure/functions');

app.http('httpTrigger1', {
    methods: ['GET'],
    authLevel: 'anonymous',
    route: 'products/{category:alpha}/{id:int?}',
    handler: async (request, context) => {
        const category = request.params.category;
        const id = request.params.id;

        return { body: `Category: ${category}, ID: ${id}` };
    },
});

As an example, the following function.json file defines a route property for an HTTP trigger with two parameters, category and id:

{
    "bindings": [
    {
        "type": "httpTrigger",
        "name": "req",
        "direction": "in",
        "methods": [ "get" ],
        "route": "products/{category:alpha}/{id:int?}"
    },
    {
        "type": "http",
        "name": "res",
        "direction": "out"
    }
    ]
}

The Functions runtime provides the request body from the context object. The following example shows how to read route parameters from context.bindingData.

module.exports = async function (context, req) {

    var category = context.bindingData.category;
    var id = context.bindingData.id;
    var message = `Category: ${category}, ID: ${id}`;

    context.res = {
        body: message;
    }
}

@app.function_name(name="httpTrigger")
@app.route(route="products/{category:alpha}/{id:int?}")

In the function.json file:

{
    "bindings": [
    {
        "type": "httpTrigger",
        "name": "req",
        "direction": "in",
        "methods": [ "get" ],
        "route": "products/{category:alpha}/{id:int?}"
    },
    {
        "type": "http",
        "name": "res",
        "direction": "out"
    }
    ]
}

@app.table_input(arg_name="product", table_name="products", 
                 row_key="{id}", partition_key="products",
                 connection="AzureWebJobsStorage")

{
    "type": "table",
    "direction": "in",
    "name": "product",
    "partitionKey": "products",
    "tableName": "products",
    "rowKey": "{id}"
}

import { app, HttpRequest, HttpResponseInit, input, InvocationContext } from '@azure/functions';

const tableInput = input.table({
    connection: 'MyStorageConnectionAppSetting',
    partitionKey: 'products',
    tableName: 'products',
    rowKey: '{id}',
});

export async function httpTrigger1(request: HttpRequest, context: InvocationContext): Promise<HttpResponseInit> {
    return { jsonBody: context.extraInputs.get(tableInput) };
}

app.http('httpTrigger1', {
    methods: ['GET'],
    authLevel: 'anonymous',
    route: 'products/{id}',
    extraInputs: [tableInput],
    handler: httpTrigger1,
});

TypeScript samples aren't documented for model v3.

const { app, input } = require('@azure/functions');

const tableInput = input.table({
    connection: 'MyStorageConnectionAppSetting',
    partitionKey: 'products',
    tableName: 'products',
    rowKey: '{id}',
});

app.http('httpTrigger1', {
    methods: ['GET'],
    authLevel: 'anonymous',
    route: 'products/{id}',
    extraInputs: [tableInput],
    handler: async (request, context) => {
        return { jsonBody: context.extraInputs.get(tableInput) };
    },
});

{
    "type": "table",
    "direction": "in",
    "name": "product",
    "connection": "MyStorageConnectionAppSetting",
    "partitionKey": "products",
    "tableName": "products",
    "rowKey": "{id}"
}

The authenticated user is available via HTTP Headers.

using System.Net;
using Microsoft.AspNetCore.Mvc;
using System.Security.Claims;

public static IActionResult Run(HttpRequest req, ILogger log)
{
    ClaimsPrincipal identities = req.HttpContext.User;
    // ...
    return new OkObjectResult();
}

Alternatively, the ClaimsPrincipal can simply be included as an extra parameter in the function signature:

using System.Net;
using Microsoft.AspNetCore.Mvc;
using System.Security.Claims;
using Newtonsoft.Json.Linq;

public static void Run(JObject input, ClaimsPrincipal principal, ILogger log)
{
    // ...
    return;
}

Authorization defaults to the anonymous level.

Authorization defaults to the function level.