How to configure file upload for PHP/Node.js on Render | Disk, environment variables & S3 integration

Render is a popular cloud platform as a Heroku alternative. Unlike Vercel or Netlify, it uses a persistent process (Web Service) model rather than serverless, which changes the file upload architecture. This article covers Render's persistent storage (Disk) configuration, how to modify <code>upload_max_filesize</code> in PHP environments, S3 setup using environment variables, and Infrastructure as Code (IaC) examples with <code>render.yaml</code> (Blueprint).

What is Render Disk (Persistent Storage)?

Render's Web Service is ephemeral by default (the file system resets on redeploy). To persist uploaded files, add a Disk.

Render Disk does not support scaling out (multiple instances), so S3 integration is recommended for production file uploads. Disk is suitable for development, staging environments, or single-instance deployments.

Disk configuration in Render Dashboard

Disks can be added from the Web Service settings in the Render Dashboard.

# render.yaml（Blueprint）での Disk 設定
services:
  - type: web
    name: my-app
    runtime: node
    buildCommand: npm install && npm run build
    startCommand: npm start
    disk:
      name: uploads-disk
      mountPath: /app/uploads  # アプリ内でのマウントパス
      sizeGB: 10               # 10GB のディスク
    envVars:
      - key: UPLOAD_DIR
        value: /app/uploads

// Node.js での Disk へのファイル保存
const path = require('path');
const fs = require('fs');

const UPLOAD_DIR = process.env.UPLOAD_DIR || path.join(__dirname, 'uploads');

// アップロードディレクトリが存在しない場合は作成
if (!fs.existsSync(UPLOAD_DIR)) {
  fs.mkdirSync(UPLOAD_DIR, { recursive: true });
}

// multer の設定例（Disk ストレージ）
const multer = require('multer');

const storage = multer.diskStorage({
  destination: (req, file, cb) => {
    cb(null, UPLOAD_DIR);
  },
  filename: (req, file, cb) => {
    const uniqueSuffix = `${Date.now()}-${Math.round(Math.random() * 1e9)}`;
    const ext = path.extname(file.originalname);
    cb(null, `upload-${uniqueSuffix}${ext}`);
  },
});

const upload = multer({
  storage,
  limits: { fileSize: 50 * 1024 * 1024 }, // 50MB
  fileFilter: (req, file, cb) => {
    const allowedTypes = ['image/jpeg', 'image/png', 'image/webp', 'application/pdf'];
    if (allowedTypes.includes(file.mimetype)) {
      cb(null, true);
    } else {
      cb(new Error('許可されていないファイル形式です。'));
    }
  },
});

upload_max_filesize configuration in PHP environment

For PHP apps on Render (Docker-based), you can adjust upload size by modifying <code>php.ini</code> settings. Render offers flexibility with arbitrary Docker configuration, surpassing other hosting services.

# Dockerfile（PHP アプリ）
FROM php:8.2-fpm

# 必要な拡張をインストール
RUN docker-php-ext-install pdo pdo_mysql

# php.ini の設定をオーバーライド
RUN echo "upload_max_filesize = 100M" > /usr/local/etc/php/conf.d/uploads.ini \
 && echo "post_max_size = 110M" >> /usr/local/etc/php/conf.d/uploads.ini \
 && echo "memory_limit = 256M" >> /usr/local/etc/php/conf.d/uploads.ini \
 && echo "max_execution_time = 120" >> /usr/local/etc/php/conf.d/uploads.ini \
 && echo "max_input_time = 120" >> /usr/local/etc/php/conf.d/uploads.ini

WORKDIR /var/www/html
COPY . .

EXPOSE 9000
CMD ["php-fpm"]

# php.ini（直接配置する場合）
; ファイルアップロードの有効化
file_uploads = On

; 1ファイルあたりの上限
upload_max_filesize = 100M

; POST データ全体の上限（upload_max_filesize より大きくする）
post_max_size = 110M

; PHP スクリプトのメモリ上限
memory_limit = 256M

; スクリプトの最大実行時間（秒）
max_execution_time = 120

; ファイル入力待ちの最大時間（秒）
max_input_time = 120

; 一時ファイルのディレクトリ（Render の場合は /tmp を使用）
upload_tmp_dir = /tmp

<?php
// .htaccess が使えない場合は ini_set() で実行時に変更（共有ホスティングでは制限あり）
// Render（Docker）では Dockerfile での設定が確実

// ini_set() による実行時オーバーライド（一部の設定のみ有効）
ini_set('memory_limit', '256M');
// upload_max_filesize と post_max_size は実行時変更不可（php.ini での設定が必要）

// 設定値の確認
echo ini_get('upload_max_filesize'); // "100M"
echo ini_get('post_max_size');       // "110M"
echo ini_get('memory_limit');        // "256M"

S3 configuration using environment variables

Set environment variables in Render Dashboard or <code>render.yaml</code> and access AWS S3 from your app. Use Render's secret management feature for sensitive information, and include only the keys in <code>render.yaml</code>.

# render.yaml（Blueprint）— シークレットはキーのみ定義
services:
  - type: web
    name: my-php-app
    runtime: docker
    dockerfilePath: ./Dockerfile
    envVars:
      # 非シークレット（値を直接記載）
      - key: AWS_REGION
        value: ap-northeast-1
      - key: AWS_S3_BUCKET
        value: my-app-uploads

      # シークレット（Render Dashboard で値を設定）
      - key: AWS_ACCESS_KEY_ID
        sync: false          # sync: false でダッシュボードで手動入力
      - key: AWS_SECRET_ACCESS_KEY
        sync: false

      # または Render の Environment Group を参照
      - fromGroup: aws-credentials

    disk:
      name: tmp-uploads
      mountPath: /tmp/uploads
      sizeGB: 5

<?php
// PHP での AWS SDK を使った S3 アップロード
require 'vendor/autoload.php';

use Aws\S3\S3Client;
use Aws\Exception\AwsException;

$s3 = new S3Client([
    'version' => 'latest',
    'region'  => getenv('AWS_REGION'),
    'credentials' => [
        'key'    => getenv('AWS_ACCESS_KEY_ID'),
        'secret' => getenv('AWS_SECRET_ACCESS_KEY'),
    ],
]);

function uploadToS3(array $file, string $bucket): array
{
    global $s3;

    $key = 'uploads/' . uniqid('file_', true) . '_' . basename($file['name']);

    try {
        $result = $s3->putObject([
            'Bucket'      => $bucket,
            'Key'         => $key,
            'SourceFile'  => $file['tmp_name'],
            'ContentType' => mime_content_type($file['tmp_name']),
            'ACL'         => 'private',
        ]);

        return [
            'success' => true,
            'key'     => $key,
            'url'     => $result['ObjectURL'],
        ];
    } catch (AwsException $e) {
        return ['success' => false, 'error' => $e->getMessage()];
    }
}

// アップロード処理
if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_FILES['file'])) {
    $file = $_FILES['file'];

    // バリデーション
    $maxSize = 50 * 1024 * 1024; // 50MB
    if ($file['size'] > $maxSize) {
        http_response_code(413);
        echo json_encode(['error' => 'ファイルが大きすぎます（上限50MB）。']);
        exit;
    }

    $allowedMimes = ['image/jpeg', 'image/png', 'image/webp', 'application/pdf'];
    $detectedMime = mime_content_type($file['tmp_name']); // サーバー側でMIMEを検出
    if (!in_array($detectedMime, $allowedMimes)) {
        http_response_code(415);
        echo json_encode(['error' => '許可されていないファイル形式です。']);
        exit;
    }

    $result = uploadToS3($file, getenv('AWS_S3_BUCKET'));
    echo json_encode($result);
}

Complete configuration example in render.yaml (Blueprint)

Using Blueprint, you can manage Render infrastructure as code. You can define Web Service, database, Redis, Disk, and environment variables all together.

# render.yaml
version: "1"

services:
  # Web アプリケーション
  - type: web
    name: file-upload-app
    runtime: node
    plan: starter           # free / starter / standard / pro
    region: singapore       # oregon / frankfurt / singapore / ohio
    buildCommand: npm ci && npm run build
    startCommand: node server.js
    healthCheckPath: /health
    autoDeploy: true        # Git push で自動デプロイ

    # 永続ストレージ（スケールアウト不可）
    disk:
      name: user-uploads
      mountPath: /app/data/uploads
      sizeGB: 20

    # 環境変数
    envVars:
      - key: NODE_ENV
        value: production
      - key: PORT
        value: 3000
      - key: UPLOAD_DIR
        value: /app/data/uploads
      - key: AWS_REGION
        value: ap-northeast-1
      - key: AWS_S3_BUCKET
        value: my-production-bucket

      # シークレット（ダッシュボードで値を設定）
      - key: AWS_ACCESS_KEY_ID
        sync: false
      - key: AWS_SECRET_ACCESS_KEY
        sync: false
      - key: DATABASE_URL
        fromDatabase:
          name: app-db
          property: connectionString

  # PostgreSQL データベース
  - type: pserv
    name: app-db
    runtime: postgres
    plan: starter
    region: singapore
    databaseName: app_production