How to list the contents of a Google Drive folder by ID with the V3 API Python client?

Question

The official documentation here is not helping much on this topic. First of all it is an example on searching by mimeType, not by parent ID. And then I replaced the search term by the example in here and it still does not find anything. My code is below. Note that the function is named copy_folder just because I was actually trying to copy all files and sub-folders in a folder to a new folder and the first step is to get the contents of the source folder. And the source folder is in a team drive. The 'files' key in the response is just empty while in the folder I tested there are actually files and sub-folders.

def copy_folder(service, src, dst):
    """
    Copies a folder. It will create a new folder in dst with the same name as src,
    and copies the contents of src into the new folder
    src: Source folder's id
    dst: Destination folder's id that the source folder is going to be copied to
    """
    page_token = None
    while True:
        response = service.files().list(q="'%s' in parents" % src,
                                        supportsAllDrives=True,
                                        spaces='drive',
                                        fields='nextPageToken, files(id, name)',
                                        pageToken=page_token,
                                        ).execute()
        for file in response.get('files', []):
            # Process change
            print('Found file: %s (%s)' % (file.get('name'), file.get('id')))
        page_token = response.get('nextPageToken', None)
        if page_token is None:
            break

Answer 1

In that case, I think that in order to retrieve the files in the subfolders, it is required to use the recursive function. For this, I have created the library for achieving it. So in this answer, I would like to achieve your goal using a library of getfilelistpy. When this library is used, the script is as follows.

Sample script:

Before you use this script, please install getfilelistpy as follows.

$ pip install getfilelistpy

And, after you copied and pasted the following script, please set the variable of src.

import pickle
import os.path
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request
from getfilelistpy import getfilelist

SCOPES = 'https://www.googleapis.com/auth/drive.metadata.readonly'

creds = None

creFile = 'token_sample.pickle'
if os.path.exists(creFile):
    with open(creFile, 'rb') as token:
        creds = pickle.load(token)
if not creds or not creds.valid:
    if creds and creds.expired and creds.refresh_token:
        creds.refresh(Request())
    else:
        flow = InstalledAppFlow.from_client_secrets_file(
            'client_secret.json', SCOPES)
        creds = flow.run_local_server()
    with open(creFile, 'wb') as token:
        pickle.dump(creds, token)

src = '###'  # Please set the folder ID.
fields = 'nextPageToken, files(id, name)'
resource = {
    "oauth2": creds,
    "id": src,
    "fields": fields,
}
res = getfilelist.GetFileList(resource)
print(dict(res))

• In this case, you can also use the scopes of https://www.googleapis.com/auth/drive.readonly and https://www.googleapis.com/auth/drive.

Note:

• When you want to retrieve the file list just under the specific folder, you can also use the following script.

    src = '###'  # Please set the folder ID.
    service = build('drive', 'v3', credentials=creds)
    fields = 'nextPageToken, files(id, name)'
    q = "'%s' in parents" % src
    values = []
    nextPageToken = ""
    while True:
        res = service.files().list(q=q, fields=fields, pageSize=1000, pageToken=nextPageToken or "", includeItemsFromAllDrives=True, supportsAllDrives=True).execute()
        values.extend(res.get("files"))
        nextPageToken = res.get("nextPageToken")
        if nextPageToken is None:
            break
    print(values)
  

• In this case, in order to retrieve the file list from the shared Drive, please use supportsAllDrives=True and includeItemsFromAllDrives=True.

• If you cannot retrieve the files, please also add corpora="drive", driveId="###driveId###".

References:

• Files: list
• getfilelistpy