Authorize Many Users Dynamically

Authorizing Users dynamically and enable multiple users to connect their WePay account with your app is simple. Set up wepay.yml to your needs, leaving account_id and access_token blank, and create a controller action to redirect the user to WePay with your custom redirect_uri. For example:

# config/routes.rb
...

resources :users do
  match 'wepay_connect', :to => 'users#wepay_connect'
  match 'wepay_auth', :to => 'users#wepay_auth'
end

# app/controllers/users_controller.rb
...

def wepay_connect
  @user = User.find(params[:id])
  wepay_gateway = WepayRails::Payments::Gateway.new
  redirect_to wepay_gateway.auth_code_url( user_wepay_auth_url(@user, :only_path => false) )
end

This will redirect the user to WePay for authentication. Once they log in or create an account, they will be redirected to user_wepay_auth_url(@user, :only_path => false). Call get_access_token on a WepayRails::Payments::Gateway object to authorize a user and return the access token. Following the above example, the action could look like this:

# app/controllers/users_controller.rb
...

def wepay_auth
  if params[:code].present?
    wepay_gateway = WepayRails::Payments::Gateway.new
    access_token = wepay_gateway.get_access_token(params[:code], user_wepay_auth_url(@user, :only_path => false) )
    if @user.update_attributes(:wepay_token => access_token, :wepay_id => wepay_gateway.account_id)
      flash[:success] = "Your WePay account is now connected!  You're ready to start receiving payments!"
    end
  else
    flash[:notice] = "Your WePay account was not connected."
    redirect_to root_path
  end
end

In the above example, wepay_gateway is an instance of WepayRails::Payments::Gateway which has two attr_accessor methods: :access_token and :account_id. Calling get_access_token with a valid access key in the params hash (returned as params[:code]) will return the :access_token attribute, and also set the :account_id attribute to the user's WePay account id.

With a valid access_token and account_id, you are now able to dynamically create accounts for users of your application and accept payments. A User model might have the following code:

# app/models/user.rb
...

before_save :create_wepay_account, if: wepay_token_changed?

private

  def create_wepay_account
    wepay_gateway = WepayRails::Payments::Gateway.new(self.user.wepay_token)
    response = wepay_gateway.create_account({
      :name => "New User Account",
      :description => "This account will collect payments on behalf of my app.,
      :reference_id => self.id, # optional, leave blank for WePay to generate a reference_id for you
      :image_uri => "http://www.example.com/assets/account-graphic.png"
    })
    self.wepay_account_id = response[:account_id]
    self.save
  end

In the above code, response is a hash of the JSON response returned by WePay. You can see possible options and responses on WePay's website: https://www.wepay.com/developer/reference. If an error is returned by WePay, an instance of WepayRails::Exceptions will be raised. Rails provides a great way to handle exceptions like this at the controller level by adding rescue_from MyException, :with => my_rescue_method to the top of your controller and creating the associated rescue method.