HTTP request body

Parses a request body.

Code sample

C#

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

using Google.Cloud.Functions.Framework;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Primitives;
using System;
using System.IO;
using System.Net;
using System.Net.Mime;
using System.Text;
using System.Text.Json;
using System.Threading.Tasks;

namespace ParseContentType;

public class Function : IHttpFunction
{
    public async Task HandleAsync(HttpContext context)
    {
        HttpRequest request = context.Request;
        HttpResponse response = context.Response;

        string name = null;
        ContentType contentType = new ContentType(request.ContentType);

        switch (contentType.MediaType)
        {
            case "application/json":
            {
                // '{"name":"John"}'
                using TextReader reader = new StreamReader(request.Body);
                string json = await reader.ReadToEndAsync();
                JsonElement body = JsonSerializer.Deserialize<JsonElement>(json);
                if (body.TryGetProperty("name", out JsonElement property) && property.ValueKind == JsonValueKind.String)
                {
                    name = property.GetString();
                }
                break;
            }
            case "application/octet-stream":
            {
                // 'John', encoded to bytes using UTF-8, then encoded as base64
                using TextReader reader = new StreamReader(request.Body);
                string base64 = await reader.ReadToEndAsync();
                byte[] data = Convert.FromBase64String(base64);
                name = Encoding.UTF8.GetString(data);
                break;
            }
            case "text/plain":
            {
                // 'John'
                using TextReader reader = new StreamReader(request.Body);
                name = await reader.ReadLineAsync();
                break;
            }
            case "application/x-www-form-urlencoded":
            {
                // 'name=John' in the body of a POST request (not the URL)
                if (request.Form.TryGetValue("name", out StringValues value))
                {
                    name = value;
                }
                break;
            }
        }
        if (name is object)
        {
            await response.WriteAsync($"Hello {name}!", context.RequestAborted);
        }
        else
        {
            // Unrecognized content type, or the name wasn't in the content
            // (e.g. JSON without a "name" property)
            response.StatusCode = (int) HttpStatusCode.BadRequest;
        }
    }
}

Go

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

// Package http provides a set of HTTP Cloud Functions samples.
package http

import (
	"encoding/json"
	"fmt"
	"html"
	"io"
	"log"
	"net/http"

	"github.com/GoogleCloudPlatform/functions-framework-go/functions"
)

func init() {
	// Register an HTTP function with the Functions Framework
	functions.HTTP("HelloContentType", HelloContentType)
}

// HelloContentType is an HTTP Cloud function.
// It uses the Content-Type header to identify the request payload format.
func HelloContentType(w http.ResponseWriter, r *http.Request) {
	var name string

	switch r.Header.Get("Content-Type") {
	case "application/json":
		var d struct {
			Name string `json:"name"`
		}
		err := json.NewDecoder(r.Body).Decode(&d)
		if err != nil {
			log.Printf("error parsing application/json: %v", err)
		} else {
			name = d.Name
		}
	case "application/octet-stream":
		body, err := io.ReadAll(r.Body)
		if err != nil {
			log.Printf("error parsing application/octet-stream: %v", err)
		} else {
			name = string(body)
		}
	case "text/plain":
		body, err := io.ReadAll(r.Body)
		if err != nil {
			log.Printf("error parsing text/plain: %v", err)
		} else {
			name = string(body)
		}
	case "application/x-www-form-urlencoded":
		if err := r.ParseForm(); err != nil {
			log.Printf("error parsing application/x-www-form-urlencoded: %v", err)
		} else {
			name = r.FormValue("name")
		}
	}

	if name == "" {
		name = "World"
	}

	fmt.Fprintf(w, "Hello, %s!", html.EscapeString(name))
}

Java

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import com.google.cloud.functions.HttpFunction;
import com.google.cloud.functions.HttpRequest;
import com.google.cloud.functions.HttpResponse;
import com.google.gson.Gson;
import com.google.gson.JsonObject;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
import java.util.Optional;

public class ParseContentType implements HttpFunction {

  // Use GSON (https://github.com/google/gson) to parse JSON content.
  private static final Gson gson = new Gson();

  // Responds to an HTTP request using data from the request body parsed according to the
  // "content-type" header.
  @Override
  public void service(HttpRequest request, HttpResponse response)
      throws IOException {
    String name = null;

    // Default values avoid null issues (with switch/case) and exceptions from get() (optionals)
    String contentType = request.getContentType().orElse("");

    switch (contentType) {
      case "application/json":
        // '{"name":"John"}'
        JsonObject body = gson.fromJson(request.getReader(), JsonObject.class);
        if (body.has("name")) {
          name = body.get("name").getAsString();
        }
        break;
      case "application/octet-stream":
        // 'John', stored in a Buffer
        name = new String(Base64.getDecoder().decode(request.getInputStream().readAllBytes()),
            StandardCharsets.UTF_8);
        break;
      case "text/plain":
        // 'John'
        name = request.getReader().readLine();
        break;
      case "application/x-www-form-urlencoded":
        // 'name=John' in the body of a POST request (not the URL)
        Optional<String> nameParam = request.getFirstQueryParameter("name");
        if (nameParam.isPresent()) {
          name = nameParam.get();
        }
        break;
      default:
        // Invalid or missing "Content-Type" header
        response.setStatusCode(HttpURLConnection.HTTP_UNSUPPORTED_TYPE);
        return;
    }

    // Verify that a name was provided
    if (name == null) {
      response.setStatusCode(HttpURLConnection.HTTP_BAD_REQUEST);
    }

    // Respond with a name
    var writer = new PrintWriter(response.getWriter());
    writer.printf("Hello %s!", name);
  }
}

Node.js

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

const escapeHtml = require('escape-html');
const functions = require('@google-cloud/functions-framework');

/**
 * Responds to an HTTP request using data from the request body parsed according
 * to the "content-type" header.
 *
 * @param {Object} req Cloud Function request context.
 * @param {Object} res Cloud Function response context.
 */
functions.http('helloContent', (req, res) => {
  let name;

  switch (req.get('content-type')) {
    // '{"name":"John"}'
    case 'application/json':
      ({name} = req.body);
      break;

    // 'John', stored in a Buffer
    case 'application/octet-stream':
      name = req.body.toString(); // Convert buffer to a string
      break;

    // 'John'
    case 'text/plain':
      name = req.body;
      break;

    // 'name=John' in the body of a POST request (not the URL)
    case 'application/x-www-form-urlencoded':
      ({name} = req.body);
      break;
  }

  res.status(200).send(`Hello ${escapeHtml(name || 'World')}!`);
});

PHP

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

use Psr\Http\Message\ServerRequestInterface;

function helloContent(ServerRequestInterface $request): string
{
    $name = 'World';
    $body = $request->getBody()->getContents();
    switch ($request->getHeaderLine('content-type')) {
        // '{"name":"John"}'
        case 'application/json':
            if (!empty($body)) {
                $json = json_decode($body, true);
                if (json_last_error() != JSON_ERROR_NONE) {
                    throw new RuntimeException(sprintf(
                        'Could not parse body: %s',
                        json_last_error_msg()
                    ));
                }
                $name = $json['name'] ?? $name;
            }
            break;
            // 'John', stored in a stream
        case 'application/octet-stream':
            $name = $body;
            break;
            // 'John'
        case 'text/plain':
            $name = $body;
            break;
            // 'name=John' in the body of a POST request (not the URL)
        case 'application/x-www-form-urlencoded':
            parse_str($body, $data);
            $name = $data['name'] ?? $name;
            break;
    }

    return sprintf('Hello %s!', htmlspecialchars($name));
}

Python

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import functions_framework


from markupsafe import escape

@functions_framework.http
def hello_content(request):
    """Responds to an HTTP request using data from the request body parsed
    according to the "content-type" header.
    Args:
        request (flask.Request): The request object.
        <https://flask.palletsprojects.com/en/1.1.x/api/#incoming-request-data>
    Returns:
        The response text, or any set of values that can be turned into a
        Response object using `make_response`
        <https://flask.palletsprojects.com/en/1.1.x/api/#flask.make_response>.
    """
    content_type = request.headers["content-type"]
    if content_type == "application/json":
        request_json = request.get_json(silent=True)
        if request_json and "name" in request_json:
            name = request_json["name"]
        else:
            raise ValueError("JSON is invalid, or missing a 'name' property")
    elif content_type == "application/octet-stream":
        name = request.data
    elif content_type == "text/plain":
        name = request.data
    elif content_type == "application/x-www-form-urlencoded":
        name = request.form.get("name")
    else:
        raise ValueError(f"Unknown content type: {content_type}")
    return f"Hello {escape(name)}!"

Ruby

To authenticate to Cloud Run functions, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

require "functions_framework"
require "json"

FunctionsFramework.http "http_content" do |request|
  # The request parameter is a Rack::Request object.
  # See https://www.rubydoc.info/gems/rack/Rack/Request
  content_type = request.content_type
  case content_type
  # '{"name":"John"}'
  when "application/json"
    name = (JSON.parse(request.body.read.to_s)["name"] rescue nil)
  # "John", stored in a Buffer
  when "application/octet-stream"
    name = request.body.read.to_s # Convert buffer to a string
  # "John"
  when "text/plain"
    name = request.body.read.to_s
  # "name=John" in the body of a POST request (not the URL)
  when "application/x-www-form-urlencoded"
    name = (request.params["name"] rescue nil)
  end

  name ||= "World"

  # Return the response body as a string.
  # You can also return a Rack::Response object, a Rack response array, or
  # a hash which will be JSON-encoded into a response.
  "Hello #{name}!"
end

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