---
title: Storage Options
description: Configure media storage with R2, S3, or local filesystem.
---

import { Aside, Tabs, TabItem } from "@astrojs/starlight/components";

EmDash stores uploaded media (images, documents, videos) in a configurable storage backend. Choose based on your deployment platform and requirements.

## Overview

| Storage        | Best For           | Features                    |
| -------------- | ------------------ | --------------------------- |
| **R2 Binding** | Cloudflare Workers | Zero-config, fast           |
| **S3**         | Any platform       | Signed uploads, CDN support |
| **Local**      | Development        | Simple filesystem storage   |

## Cloudflare R2 (Binding)

Use R2 bindings when deploying to Cloudflare Workers for the fastest integration.

```js title="astro.config.mjs"
import emdash from "emdash/astro";
import { r2 } from "@emdash-cms/cloudflare";

export default defineConfig({
	integrations: [
		emdash({
			storage: r2({ binding: "MEDIA" }),
		}),
	],
});
```

### Configuration

| Option      | Type     | Description                           |
| ----------- | -------- | ------------------------------------- |
| `binding`   | `string` | R2 binding name from `wrangler.jsonc` |
| `publicUrl` | `string` | Optional public URL for the bucket    |

### Setup

Add the R2 binding to your Wrangler configuration:

<Tabs>
  <TabItem label="wrangler.jsonc">
    ```jsonc
    {
      "r2_buckets": [
        {
          "binding": "MEDIA",
          "bucket_name": "emdash-media"
        }
      ]
    }
    ```
  </TabItem>
  <TabItem label="wrangler.toml">
    ```toml
    [[r2_buckets]]
    binding = "MEDIA"
    bucket_name = "emdash-media"
    ```
  </TabItem>
</Tabs>

### Public Access

For public media URLs, enable public access on your R2 bucket:

1. Go to Cloudflare Dashboard > R2 > your bucket
2. Enable public access under Settings
3. Add the public URL to your config:

```js
storage: r2({
	binding: "MEDIA",
	publicUrl: "https://pub-xxxx.r2.dev",
});
```

<Aside type="tip">
	Connect a custom domain to R2 for branded URLs like `https://media.example.com`.
</Aside>

<Aside type="note">
	R2 bindings do not support signed upload URLs. If you need direct client uploads, use the S3
	adapter with R2 credentials instead.
</Aside>

## S3-Compatible Storage

The S3 adapter works with Cloudflare R2 (via S3 API), MinIO, and other S3-compatible services.

```js title="astro.config.mjs"
import emdash, { s3 } from "emdash/astro";

export default defineConfig({
	integrations: [
		emdash({
			storage: s3({
				endpoint: process.env.S3_ENDPOINT,
				bucket: process.env.S3_BUCKET,
				accessKeyId: process.env.S3_ACCESS_KEY_ID,
				secretAccessKey: process.env.S3_SECRET_ACCESS_KEY,
				region: "auto", // Optional, defaults to "auto"
				publicUrl: process.env.S3_PUBLIC_URL, // Optional CDN URL
			}),
		}),
	],
});
```

### Configuration

| Option            | Type     | Description                    |
| ----------------- | -------- | ------------------------------ |
| `endpoint`        | `string` | S3 endpoint URL                |
| `bucket`          | `string` | Bucket name                    |
| `accessKeyId`     | `string` | Access key                     |
| `secretAccessKey` | `string` | Secret key                     |
| `region`          | `string` | Region (default: `"auto"`)     |
| `publicUrl`       | `string` | Optional CDN or public URL     |

### R2 via S3 API

Use S3 credentials with R2 for features like signed upload URLs:

```js
storage: s3({
	endpoint: "https://<account-id>.r2.cloudflarestorage.com",
	bucket: "emdash-media",
	accessKeyId: process.env.R2_ACCESS_KEY_ID,
	secretAccessKey: process.env.R2_SECRET_ACCESS_KEY,
	publicUrl: "https://pub-xxxx.r2.dev",
});
```

Generate R2 API credentials in the Cloudflare dashboard under R2 > Manage R2 API Tokens.

### MinIO

```js
storage: s3({
	endpoint: "https://minio.example.com",
	bucket: "emdash-media",
	accessKeyId: process.env.MINIO_ACCESS_KEY,
	secretAccessKey: process.env.MINIO_SECRET_KEY,
	publicUrl: "https://minio.example.com/emdash-media",
});
```

## Local Filesystem

Use local storage for development. Files are stored in a directory on disk.

```js title="astro.config.mjs"
import emdash, { local } from "emdash/astro";

export default defineConfig({
	integrations: [
		emdash({
			storage: local({
				directory: "./uploads",
				baseUrl: "/_emdash/api/media/file",
			}),
		}),
	],
});
```

### Configuration

| Option      | Type     | Description                     |
| ----------- | -------- | ------------------------------- |
| `directory` | `string` | Directory path for file storage |
| `baseUrl`   | `string` | Base URL for serving files      |

The `baseUrl` should match EmDash's media file endpoint (`/_emdash/api/media/file`) unless you configure a custom static file server.

<Aside type="caution">
	Local storage does not support signed upload URLs. Files are uploaded through the server, which
	may be slower for large files.
</Aside>

## Environment-Based Configuration

Switch storage backends based on environment:

```js title="astro.config.mjs"
import emdash, { s3, local } from "emdash/astro";
import { r2 } from "@emdash-cms/cloudflare";

const storage = import.meta.env.PROD
	? r2({ binding: "MEDIA" })
	: local({
			directory: "./uploads",
			baseUrl: "/_emdash/api/media/file",
		});

export default defineConfig({
	integrations: [emdash({ storage })],
});
```

## Signed Uploads

The S3 adapter supports signed upload URLs, allowing clients to upload directly to storage without passing through your server. This improves performance for large files.

Signed uploads are automatic when using the S3 adapter. The admin interface uses them when available.

Adapters that support signed uploads:

- **S3** (including R2 via S3 API)

Adapters that do not support signed uploads:

- **R2 binding** (use S3 adapter with R2 credentials instead)
- **Local**

## Storage Interface

All storage adapters implement the same interface:

```typescript
interface Storage {
	upload(options: {
		key: string;
		body: Buffer | Uint8Array | ReadableStream;
		contentType: string;
	}): Promise<UploadResult>;

	download(key: string): Promise<DownloadResult>;
	delete(key: string): Promise<void>;
	exists(key: string): Promise<boolean>;
	list(options?: ListOptions): Promise<ListResult>;
	getSignedUploadUrl(options: SignedUploadOptions): Promise<SignedUploadUrl>;
	getPublicUrl(key: string): string;
}
```

This consistency allows switching storage backends without changing application code.
