How to sync a file through Google Drive API?

Question

API

I have an application written in C++ and Qt5. It creates the file I need. How to create "upload/download" to/from Google Driv'a, respectively, taking into account the fact that there is a Google account login/password. You need to create a folder on the disk at the root and upload the file to it.
In which direction to dig?

Answer 1

Well, you should probably start by reading the Google Drive API documentation .
You don't need a username and password.
Authentication is done using OAuth 2.0.
The first thing you need to do is to create an application through the Google API Console , get your application details and connect the Google Drive API to it.
I will describe one of the authentication methods using a confirmation code below.

1. First, open the URL to the user (in the system browser):

   https://accounts.google.com/o/oauth2/auth?scope={scope}&redirect_uri={redirect_uri}&response_type=code&client_id={client_id}

   
   (This can be done using the QDesktopServices::openUrl method
   where {scope} = " https://www.googleapis.com/auth/drive "
   {redirect_uri} = "urn:ietf:wg:oauth:2.0:oob"
   {client_id }= blablabla.apps.googleusercontent.com (your app ID)
   The user confirms access and copies the verification code
   You are prompted to enter a verification code in your app The user enters it.
   
2. To get an access token, you need to send a POST request to the https://www.googleapis.com/oauth2/v3/token
   server with the following parameters:
   code - confirmation code entered by the user
   client_id - your application ID (blablabla.apps.googleusercontent.com)
   client_secret - secret key of your application
   redirect_uri - the same redirect uri as in the first case
   grant_type = "authorization_code" The
   request can be made using qnetworkaccessmanager
   In response, you get an access_token that will need to be used for requests to the Google Drive API.
   Also in the response there will be a refresh_token, which is needed to update the access_token.
   
3. To create a folder, you will need to send a POST request to the URL:
   https://www.googleapis.com/drive/v3/files Write
   in the request headers:
   

   Authorization:  Bearer <полученный access_token>
   Content-Type: application/json

   
   Send json in request body:
   

   {
      "title": "Название папки"
      "mimeType":  "application/vnd.google-apps.folder"
   }

   
   In response, you will receive json with the folder ID.
   How to download the file is described

Here, in
short, everything is elementary.