# Dropbox as a cloud storage

Source: https://blog.fortrabbit.com/new-app-cloud-storage-dropbox
Created: 2015-09-04
Author: Ulrich Kautz
Tags: changelog

> How to enable Dropbox as your App's persistent cloud storage.


## Using Dropbox as a static data resource for a modern PHP App

We have recently written about why and how to [use AWS S3 as a cloud storage](/new-app-cloud-storage-s3) for your PHP App, especially for users of our [New Apps](/new-apps-are-here). Many have a Dropbox account. Now, you can also "misue" your Dropbox to store your Apps uploads and other static assets. The here described work-flow is quirky, we don't really recommend to use it, but we want to share with you what we have learned:

## Setup a folder with Dropbox

First, you'll need to setup a public folder with Dropbox. If you don't already have a folder named `Public` on top level, please create a folder called `Public` on top level and then click [here](https://www.dropbox.com/enable_public_folder), to enable it — **quirk**.

Within the public folder, create a sub-folder for your App, eg `my-app`

![](/images/01-create-folder-in-public.jpg)

Once you did that, it should look like this:

![](/images/02-folder-created-in-public.jpg)

Switch now into that folder, upload something (eg a random `.html` file) and copy it's public link:

![](/images/04-copy-public-link-2.jpg)

It should look somthing like this:

`https://dl.dropboxusercontent.com/u/123123123/my-app/some-file.html`

The important part you need to remember is of course

`https://dl.dropboxusercontent.com/u/123123123/my-app/`

## Setup developer credentials for Dropbox

Simplified, Dropbox knows two kind of permissions:

1. Access to a dedicated _App folder_
2. Access to everything

Since you must use the `Public` folder to make your files accessible by everybody, there is no choice but to use access to everything — **major quirk**.

If you're logged in, just go to the [App create page](https://www.dropbox.com/developers/apps/create):

![](/images/05-create-app.jpg)

Click on _Create app_. On the next page generate you need to get your App secret (click on `Show` right to _App secret_) and must generate a new access token (click on `Generate` below _Generate access token_). The App key is not needed.

That's about it for Dropbox.

## Using Flysystem to upload

Now that all of that is done, let's try to read & write files with the Dropbox adapter for flysystem. You want to install `league/flysystem-dropbox`, which depends on `league/flysystem` via Composer.

Following a simplistic upload handler:



```php
<?php
use League\Flysystem\Dropbox\DropboxAdapter;
use League\Flysystem\Filesystem;
use Dropbox\Client;

include __DIR__. "/vendor/autoload.php";

// access token and app secret from before.. you don't need the app key
$client     = new Client($accessToken, $appSecret);
$adapter    = new DropboxAdapter($client, "Public/my-app");
$filesystem = new Filesystem($adapter);

$stream = fopen($_FILES[$uploadname]['tmp_name'], 'r+');
$filesystem->writeStream('uploads/'.$_FILES[$uploadname]['name'], $stream);
fclose($stream);
```

Of course, if you are using a framework, this will be far more elegant. Checkout [these recipes](http://flysystem.thephpleague.com/recipes/).

## Delivering files

Now that's the easy part. With the public URL from above, any file you upload will be available at: `https://dl.dropboxusercontent.com/u/123123123/my-app/the-file/you-uploade.abc`

Dropbox currently does not support directory listing, which is a good thing IMHO.