Awesome

DropboxApi

Library for communicating with Dropbox API v2.

Installation

Add this line to your application's Gemfile:

gem 'dropbox_api'

And then execute:

$ bundle

Or install it yourself as:

$ gem install dropbox_api

Documentation

Please, refer to this gem's custom Dropbox API documentation. Most of the time you'll be checking the available endpoints.

Unfortunately, the documentation at RubyDoc.info is disrecommended because it lacks some nice features that have been added with YARD plugins:

Each endpoint includes its tests right below the description, this works as an example of its usage.
All endpoints are shown as methods of the Client class, just as you will use them.

Basic set up

Authorize your application

Dropbox uses OAuth, in order to use this library from your application you'll have to get an authorization code.

Once you have it, just pass it on client initialization:

DropboxApi::Client.new("VofXAX8D...")
#=> #<DropboxApi::Client ...>

Or set it as an ENV variable called DROPBOX_OAUTH_BEARER, for example:

ENV["DROPBOX_OAUTH_BEARER"] = "VofXAX8D..."
DropboxApi::Client.new
#=> #<DropboxApi::Client ...>

The official documentation on the process to get an authorization code is here, it describes the two options listed below.

Option A: Get your access token from the website

For a quick test, you can obtain an access token from the App Console in Dropbox's website. Select from My apps your application, you may need to create one if you haven't done so yet. Under your application settings, find section OAuth 2, there is a button to generate an access token.

Option B: OAuth2 Code Flow

This is typically what you will use in production, you can obtain an authorization code with a 3-step process:

# 1. Get an authorization URL.
authenticator = DropboxApi::Authenticator.new(CLIENT_ID, CLIENT_SECRET)
authenticator.auth_code.authorize_url #=> "https://www.dropbox.com/..."

# 2. Log into Dropbox and authorize your app. You need to open the
# authorization URL in your browser.

# 3. Exchange the authorization code for a reusable access token (not visible
#    to the user).
access_token = authenticator.auth_code.get_token(CODE) #=> #<OAuth2::AccessToken ...>`
access_token.token #=> "VofXAX8D..."

# Keep this token, you'll need it to initialize a `DropboxApi::Client` object:
client = DropboxApi::Client.new(access_token: access_token)

# For backwards compatibility, the following also works:
client = DropboxApi::Client.new(access_token.token)

Integration with Rails

If you have a Rails application, you might be interested in this setup guide.

Using refresh tokens

Access tokens are short-lived by default (as of September 30th, 2021), applications that require long-lived access to the API without additional interaction with the user should use refresh tokens.

The process is similar but a token refresh might seamlessly occur as you perform API calls. When this happens you'll need to store the new token hash if you want to continue using this session, you can use the on_token_refreshed callback to do this.

# 1. Get an authorization URL, requesting offline access type.
authenticator = DropboxApi::Authenticator.new(CLIENT_ID, CLIENT_SECRET)
authenticator.auth_code.authorize_url(token_access_type: 'offline')

# 2. Log into Dropbox and authorize your app. You need to open the
#    authorization URL in your browser.

# 3. Exchange the authorization code for a reusable access token
access_token = authenticator.auth_code.get_token(CODE) #=> #<OAuth2::AccessToken ...>`

# You can now use the access token to initialize a DropboxApi::Client, you
# should also provide a callback function to store the updated access token
# whenever it's refreshed.
client = DropboxApi::Client.new(
  access_token: access_token,
  on_token_refreshed: lambda { |new_token_hash|
    # token_hash is a serializable Hash, something like this:
    # {
    #   "uid"=>"440",
    #   "token_type"=>"bearer",
    #   "scope"=>"account_info.read account_info.write...",
    #   "account_id"=>"dbid:AABOLtA1rT6rRK4vajKZ...",
    #   :access_token=>"sl.A5Ez_CBsqJILhDawHlmXSoZEhLZ4nuLFVRs6AJ...",
    #   :refresh_token=>"iMg4Me_oKYUAAAAAAAAAAapQixCgwfXOxuubCuK_...",
    #   :expires_at=>1632948328
    # }
    SomewhereSafe.save(new_token_hash)
  }
)

Once you've gone through the process above, you can skip the steps that require user interaction in subsequent initializations of DropboxApi::Client. For example:

# 1. Initialize an authenticator
authenticator = DropboxApi::Authenticator.new(CLIENT_ID, CLIENT_SECRET)

# 2. Retrieve the token hash you previously stored somewhere safe, you can use
#    it to build a new access token.
access_token = OAuth2::AccessToken.from_hash(authenticator, token_hash)

# 3. You now have an access token, so you can initialize a client like you
#    would normally:
client = DropboxApi::Client.new(
  access_token: access_token,
  on_token_refreshed: lambda { |new_token_hash|
    SomewhereSafe.save(new_token_hash)
  }
)

Performing API calls

Once you've initialized a client, for example:

client = DropboxApi::Client.new("VofXAX8D...")
#=> #<DropboxApi::Client ...>

You can perform an API call like this:

result = client.list_folder "/sample_folder"
#=> #<DropboxApi::Results::ListFolderResult>
result.entries
#=> [#<DropboxApi::Metadata::Folder>, #<DropboxApi::Metadata::File>]
result.has_more?
#=> false

The instance of Client we've initialized is the one you'll be using to perform API calls. You can check the class' documentation to find all available endpoints.

Large file uploads

If you need to upload files larger than 150MB the default #upload endpoint won't work. Instead, you need to start a upload session and upload the file in small chunks.

To make this easier, the method upload_by_chunks will handle this for you, example:

client = DropboxApi::Client.new("VofXAX8D...")
#=> #<DropboxApi::Client ...>
File.open("large_file.avi") do |f|
  client.upload_by_chunks "/remote_path.txt", f
end

Check out the method documentation to find out all available options.

Accessing Team Folders

In order to access your team scope you need to add the namespace_id to you request headers. This can be done using the middlewere layer as per the below:

client = DropboxApi::Client.new("VofXAX8D...")
#=> #<DropboxApi::Client ...>
client.namespace_id = client.get_current_account.root_info.root_namespace_id

client.list_folder('')
#=> Now returns the team folders

You could unset the namespace ID at any point afterwards with just:

client.namespace_id = nil

Dependencies

This gem depends on oauth2 and faraday.

It has official support for Ruby versions 2.x.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

Testing

I recommend you to use a test account other than your main one.

We use VCR to record the HTTP calls to Dropbox, however we sometimes need to regenerate the cassettes. Let's take list_folder as an example to show what would be the procedure to do so:

Manually delete the existing cassettes in spec/fixtures/vcr_cassettes/list_folder/*.yml.
Run the task to build the scaffolding in your Dropbox account so the tests will pass. If it doesn't exist you may need to write it yourself, check the DropboxScaffoldBuilder class to find all existing scaffold builders.
```
DROPBOX_OAUTH_BEARER=YOUR_AUTH_BEARER rake test:build_scaffold[list_folder]
```
Note that you'll have to type rake test:build_scaffold\[list_folder\] if you use zsh.

You can build all available scaffolds with just rake test:build_scaffold.

Run the tests and the cassettes will be written:

DROPBOX_OAUTH_BEARER=YOUR_AUTH_BEARER rspec spec/endpoints/files/list_folder_spec.rb

The OAuth bearer shouldn't have been recorded in the cassette and it should've been filtered. However, you may want to double check before pushing your updates to Github.

Tip: you can simply run export DROPBOX_OAUTH_BEARER=YOUR_AUTH_BEARER at the beginning of your work session so you don't need to prefix it in every command line.

Contributing

Any help will be much appreciated. The easiest way to help is to implement one or more of the endpoints that are still pending. To see how the endpoints are implemented, check out the lib/dropbox_api/endpoints folder.