We have an online application for landlords in our small country in Europe. And we want that users of our system, who have Google accounts, would have a possibility to create or connect Google spreadsheets (like excel tables) in our application.
I prepared several wireframes that could explain all. My comments are in the red colour.
a) Remember that we would like prepare connection also with Microsoft Office API in future. So write the code universally as you would write it if you have 3 APIs to connect.
b) 1 user in our app can have more than 1 connected external API - so, let's say I can have connected 1 Google Apps and 1 Microsoft Office.
c) In future, we will want to implement feature for granting permissions. In our system, user can invite his colleagues to cooperate with him. Users want to share some files to the colleague, but others not. Share = grant permission to read or even edit the file. But this feature will do after basic implementation of Google Spreadsheets.
d) Design doesn't matter now. Absolutely not. The easier UI, the better UI. Don't waste time.
e) We use Yii version 2.0.6.
f) If somewhere is technical error or succesfull action, the system has to return a message.
The result should be: live demo preview at your hosting
And after approving, you would send us PHP classes and methods, MySQL table structure. Just all needed.
If you have any question, please ask me. I prefere to consult lot of things at the beggining of our cooperation.
Here is a simple demo, how it should work: http://www.centario.cz/showcase-google-api.html