How to use Google sheets REST API directly to create a sheet - google-oauth

Question

I have a PHP application which, unfortunately, already uses the 1.1.4 version of the Google Client API, and I am unable to change that, which makes the 2.X version of the Google PHP Sheets API unavailable to me.
However, I'm hoping to be able to use the Google Sheets REST API directly, making my own curl calls (using Guzzle if that's at all interesting).
I'm brand new to the Google API and I've been all over their documentation, but I haven't been able to figure out how to do some basic things.
For the purposes of this question I want to simply create a new Google spreadsheet via the API, from a tool like POSTman.
I get that I first have to obtain an OAuth2 token via https://www.googleapis.com/auth/spreadsheets. The problem is that I can't quite figure out what to pass this call. I'm assuming it requires a GET since POST returns an error saying that method is unavailable.
Once I get that token, how do I use it when I POST to https://sheets.googleapis.com/v4/spreadsheets
Can someone provide a very basic example of the calls I might make directly to simply create a very basic default spreadsheet?
Or am I thinking about this all wrong? All help is appreciated.

Answer 1

If you already have an OAuth2 access token, you can pass it in the "Authorization" header:
curl -L -d '{}' \
-H "Authorization: Bearer <INSERT ACCESS TOKEN HERE>" \
-H 'Content-Type: application/json' \
https://sheets.googleapis.com/v4/spreadsheets
I just verified that curl command creates a new sheet.
Unfortunately as you already indicated, that's probably the simple part, and Getting an OAuth2 access token is more challenging.
Here's a (relatively painful, unfortunately) approach I use sometimes:
You should first create your own project in the API Console or Cloud Platform console, and configure it for your own OAuth2 client id and client secret.
Next, for just playing around, from the Google OAuth2 Developer Playground at https://developers.google.com/oauthplayground/, set your Client Id and Client Secret under the "OAuth 2.0 configuration" (it's the Settings icon - the little gear in the top right). The places to enter those will be hidden until you check "Use your own OAuth credentials". You can then get an access token, with the scopes https://www.googleapis.com/auth/spreadsheets and https://www.googleapis.com/auth/drive, by following the steps on the left.
For more playing around, you could then construct the POST right in step 3, or use the access token from Step 2 in the curl command above.
Best of luck - it's tricky stuff to get the auth parts right. There are lots of moving parts, and I'm just illustrating the high points here.
Tragedy about the library issue -- the PHP Quick Start appears to deal with the auth relatively cleanly.
Tim

Answer 2

Here's the official spreadsheets.create reference. Here's a list of Sheets API Samples. I would suggest that you leave the current version you're using and play with the PHP Quickstarts just so you can have a grasp of how it works.

Answer 3

This is going to be less than satisfying, but after fighting with it a while I looked to see if I could go against the premise of my question: That I couldn't upgrade to the latest Google Sheets PHP API.
As it turns out there was a way. That made all of this a lot easier.
Google's documentation is frustratingly incomplete, but I managed to get it all working anyway. Both of you gave me key pointers. Thanks for your help.