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 upload_max_filesize in PHP environments, S3 setup using environment variables, and Infrastructure as Code (IaC) examples with render.yaml (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 php.ini 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 render.yaml and access AWS S3 from your app. Use Render's secret management feature for sensitive information, and include only the keys in render.yaml.

# 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