Access Google Drive without OAuth2

Question

I have been rummaging through all the Google documentation on GoogleDrive SDK and the Drive API, however I cannot find out if there is a way to connect to a particular GoogleDrive without having to use OAuth2.

I realize that OAuth2 allows for the server or client to be able to connect securely to the particular Google Drive in question. However, I want to know if there is a way to simply have an API Key for the Google Drive instance and simply through that, access my files and folders. In fact I have a way to connect to the user's Google Drive already with OAuth2, but I want to only connect to mine in this way in order to automate pushing off statistical data to forms on my own Google Drive. Since it's automated I don't want to have to fill in the credential form and click "Accept" and all that, of course I realize that after that I'd be able to have a refresh token. But I really want to avoid all that if possible.

This is similar functionality to much of the APIs that Mashery allows, as well as Twilio. Only the API Key and then you can have access.

I really just need to know if this is at all possible or not, so I can either continue with the pursuit or leave it and try something different.

Answer 1

Google API's indeed work only via OAuth2.0 using a bearer token.

But you can obtain a bearer token from a GCP Service Account's JWT token. Since OAuth via JWT is automatic, no user interaction is involved.

Just create a Service Account, generate a key in JSON format, and "share" your Drive folder with that service account ([email protected]).

Note: a Service Account's key file looks like this ^(redacted):

{
    "type": "service_account",
    "project_id": "<skip>",
    "private_key_id": "<skip>",
    "private_key": "-----BEGIN PRIVATE KEY-----\n <skip> \n-----END PRIVATE KEY-----\n",
    "client_email": "<skip>@<skip>.iam.gserviceaccount.com",
    "client_id": "<skip>",
    "auth_uri": "https://accounts.google.com/o/oauth2/auth",
    "token_uri": "https://oauth2.googleapis.com/token",
    "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
    "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/<skip>%40<skip>.iam.gserviceaccount.com"
}

Example of listing files in Go:

package main

import (
    "fmt"
    "log"

    "golang.org/x/net/context"
    "google.golang.org/api/drive/v3"
    "google.golang.org/api/option"
)

func main() {
    srv, err := drive.NewService(context.Background(), option.WithCredentialsFile("key.json"))
    if err != nil {
        log.Fatal("Unable to access Drive API:", err)
    }
    r, err := srv.Files.List().PageSize(100).Fields("nextPageToken, files").Do()
    if err != nil {
        log.Fatal("Unable to list files:", err)
    }
    fmt.Println("Files:")
    for _, i := range r.Files {
        fmt.Printf("%v (%v) %v %v\n", i.Name, i.Id, i.MimeType, i.Parents)
    }
}

Output:

Files:
Test (1TMx<skip>SoYJ5) application/vnd.google-apps.folder []
Test.txt (1Ele<skip>Fh98n) text/plain [1TMx<skip>SoYJ5]
Test2.txt (3ce9x<skip>lsWds) text/plain [1TMx<skip>SoYJ5]