如何使用Python从Google Drive API初始化drive_service对象？

Question

[Google Drive API website上的所有教程都有一个对象drive_service，该对象先前已初始化到获取所提供代码段的位置，但没有说明它的用途，用途或构建方式。我正在使用Python。

This is the example I am trying to do

我能够通过quickstart.py进行身份验证，没有问题。

这是我的代码：

file_id = '0BwwA4oUTeiV1UVNwOHItT0xfa2M'
request = drive_service.files().get_media(fileId=file_id)
fh = io.BytesIO()
downloader = MediaIoBaseDownload(fh, request)
done = False
while done is False:
    status, done = downloader.next_chunk()
    print "Download %d%%." % int(status.progress() * 100)

这里有更多示例：

this one

another one

and another

Answer 1

我相信您的目标如下。

• 您想知道这些URL的service的service = build('drive', 'v3', credentials=creds)与这些URL的drive_service之间的区别。
• 您要创建This is the example I am trying to do和Here is my code:的2个脚本。
• 您确认适用于python的快速入门。

为此，这个答案如何？

1。关于service和drive_service：

service的[service = build('drive', 'v3', credentials=creds)与这些URL的drive_service相同。因此service包含使用API​​的授权（在本例中为Drive API v3。）。因此可以修改“ Python快速入门”的示例脚本，也可以用作授权脚本。

2。 This is the example I am trying to do的脚本：

这是This is the example I am trying to do的示例脚本。此示例脚本将本地文件上传到Google云端硬盘。在这种情况下，https://www.googleapis.com/auth/drive用作范围。在这里，有一个重点。您可以从快速入门中看到复制和粘贴的授权脚本。

在本地文件夹中，当您运行快速入门脚本时，已经用token.pickle的作用域创建了https://www.googleapis.com/auth/drive.metadata.readonly，请删除它，然后重新授权该作用域。这样，新作用域将反映到访问令牌中。请注意这一点。

示例脚本：

from __future__ import print_function
import pickle
import os.path
from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request

# If modifying these scopes, delete the file token.pickle.
SCOPES = ['https://www.googleapis.com/auth/drive']

def main():
    """Shows basic usage of the Drive v3 API.
    Prints the names and ids of the first 10 files the user has access to.
    """
    creds = None
    # The file token.pickle stores the user's access and refresh tokens, and is
    # created automatically when the authorization flow completes for the first
    # time.
    if os.path.exists('token.pickle'):
        with open('token.pickle', 'rb') as token:
            creds = pickle.load(token)
    # If there are no (valid) credentials available, let the user log in.
    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(
                'credentials.json', SCOPES)
            creds = flow.run_local_server(port=0)
        # Save the credentials for the next run
        with open('token.pickle', 'wb') as token:
            pickle.dump(creds, token)

    drive_service = build('drive', 'v3', credentials=creds)

    file_metadata = {'name': '###'}  # Please set filename.
    media = MediaFileUpload('###', mimetype='###', resumable=True)  # Please set filename and mimeType of the file you want to upload.
    file = drive_service.files().create(body=file_metadata, media_body=media, fields='id').execute()
    print('File ID: %s' % file.get('id'))


if __name__ == '__main__':
    main()

[在resumable=True使用MediaFileUpload时，可以通过断点续传上传大文件。

3。 Here is my code:的脚本：

这是Here is my code的示例脚本。此示例脚本将文件从Google云端硬盘下载到本地PC。在这种情况下，https://www.googleapis.com/auth/drive和/或https://www.googleapis.com/auth/drive.readonly可用作范围。在这里，作为测试用例，为了使用在以上第2节中创建的token.pickle文件，范围未从https://www.googleapis.com/auth/drive更改。因此，您可以使用脚本而无需重新授权范围。

示例脚本：

from __future__ import print_function
import pickle
import os.path
from googleapiclient.discovery import build
from google_auth_oauthlib.flow import InstalledAppFlow
from google.auth.transport.requests import Request

# If modifying these scopes, delete the file token.pickle.
SCOPES = ['https://www.googleapis.com/auth/drive']

def main():
    """Shows basic usage of the Drive v3 API.
    Prints the names and ids of the first 10 files the user has access to.
    """
    creds = None
    # The file token.pickle stores the user's access and refresh tokens, and is
    # created automatically when the authorization flow completes for the first
    # time.
    if os.path.exists('token.pickle'):
        with open('token.pickle', 'rb') as token:
            creds = pickle.load(token)
    # If there are no (valid) credentials available, let the user log in.
    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(
                'credentials.json', SCOPES)
            creds = flow.run_local_server(port=0)
        # Save the credentials for the next run
        with open('token.pickle', 'wb') as token:
            pickle.dump(creds, token)

    drive_service = build('drive', 'v3', credentials=creds)

    file_id = '0BwwA4oUTeiV1UVNwOHItT0xfa2M'
    request = drive_service.files().get_media(fileId=file_id)
    fh = io.BytesIO()
    downloader = MediaIoBaseDownload(fh, request)
    done = False
    while done is False:
        status, done = downloader.next_chunk()
        print("Download %d%%." % int(status.progress() * 100))


if __name__ == '__main__':
    main()

在此脚本中，无法导出Google Docs文件（电子表格，文档，幻灯片等）。可以下载除Google Docs文件以外的文件。因此，请注意这一点。

在这种情况下，下载的文件未创建为文件。所以请注意这一点。如果要将文件下载为文件，请将fh = io.BytesIO()修改为fh = io.FileIO("### filename ###", mode='wb')。

注意：

在这种情况下，作为重点，修改范围时，需要删除token.pickle并重新授权范围。请注意这一点。

参考：

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