gem 'model_to_googlesheet'

https://auth0.com/docs/connections/social/google

After creation, go to https://console.developers.google.com/apis/library?project=db-to-gs and enable Drive api.

Choose 'other' as an application type.

Once you get client_id and session_id, you can get a refresh_token with:

rake model_to_googlesheet:get_refresh_token client_id='274709489501-erfwefrefew14dd43fwf.apps.googleusercontent.com' client_secret='fewcerwfv3432w2r'

Once you get your client_id, client_secret and refresh_token, you can set them either globally, permodel, or permethod. Available options are include:

client_id
client_secret
refresh_token
spreadsheet - title of the spreadheet you'd like to export your data in.
worksheet - title of the worksheet you'd like to export your data in. if either worksheet or spreadsheet with such titles don't exit, they will be created.
convert_with - (optional) either symbol of method name in your model or Proc that will return hash (== columns and values to include in a worksheet created).
update - (optional, only works for separate records) true or false, whether to update rows found by :find_by option. that is, if you have googlesheet rows with unique :name values, you may want to update to set update: true, find_by: :name, so that on user.export_to_googlesheet gem will try to find a row with a name equal to user's name, and, if successful, update it (or append a new one if row wasn't found). default behavious is to append any record.
find_by - (optional, only works for separate records, necessary if update: true)

	ModelToGooglesheet.configure do |config|
		config.client_id     = client_id
		config.client_secret = client_secret
		config.refresh_token = refresh_token
	end

	exportable_to_googlesheet refresh_token: refresh_token, 
		spreadsheet: 'My App', worksheet: 'Users'

	User.last.export_to_googlesheet spreadsheet: 'Another one',
		convert_with: :exportize

provided you have a method

	def exportize
		{
			name: name.upcase,
			age:  age
		}
	end

in your model. You can also avoid creating new method with proc or lambda:

	convert_with: -> (record) { { name: record.name.upcase, age: record.age } }

If you export a collection of users, gem will recreate your worksheet and export it all to a clean one. If you export one user, gem will add it to the worksheet if it was already created and create a new one (with a spreadsheet if needed) if it couldn't find one, adding record to a newly created one.

You can clear a record with record.delete_from_googlesheet method. It requires :find_by option to be able to find a record to delete. If spreadsheet or worksheet or record were not found, just returns.

Now works with Mongoid too.