【问题标题】：How to initialize google-cloud-firestore - Python如何初始化 google-cloud-firestore - Python
【发布时间】：2021-08-03 15:44:18
【问题描述】：

from google.cloud import firestore

# Add a new document
db = firestore.Client()  # need to put credentials
doc_ref = db.collection(u'users').document(u'alovelace')
doc_ref.set({
    u'first': u'Ada',
    u'last': u'Lovelace',
    u'born': 1815
})

# Then query for documents
users_ref = db.collection(u'users')

for doc in users_ref.stream():
    print(u'{} => {}'.format(doc.id, doc.to_dict()))

这是来自https://googleapis.dev/python/firestore/latest/ 的示例代码当我运行时它显示

Traceback (most recent call last):
  File "/home/kulothungan/Purp/temp/temp.py", line 4, in <module>
    db = firestore.Client()
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/firestore_v1/client.py", line 94, in __init__
    client_options=client_options,
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/firestore_v1/base_client.py", line 128, in __init__
    _http=None,
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/client.py", line 277, in __init__
    _ClientProjectMixin.__init__(self, project=project, credentials=credentials)
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/client.py", line 225, in __init__
    project = self._determine_default(project)
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/client.py", line 244, in _determine_default
    return _determine_default_project(project)
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/cloud/_helpers.py", line 186, in _determine_default_project
    _, project = google.auth.default()
  File "/home/kulothungan/.local/lib/python3.6/site-packages/google/auth/_default.py", line 483, in default
    raise exceptions.DefaultCredentialsError(_HELP_MESSAGE)
google.auth.exceptions.DefaultCredentialsError: Could not automatically determine credentials. Please set GOOGLE_APPLICATION_CREDENTIALS or explicitly create credentials and re-run the application. For more information, please see https://cloud.google.com/docs/authentication/getting-started

但我不知道如何初始化它，而且我不想通过使用环境变量来做到这一点如果有人知道请告诉我提前致谢

【问题讨论】：

标签： python firebase google-cloud-firestore

【解决方案1】：

如果您有权访问此特定项目，则需要转到 Google 云控制台服务帐户页面 here 并创建一个服务帐户以访问 firestore。 Service account creation。根据需要为服务帐户提供数据存储区roles 之一。

创建后，您必须为服务帐户生成密钥。您可以从服务帐户页面上的“密钥”标签执行此操作。

选择 JSON 格式。您将获得一个名为keys.json 的文件。将其存储在您的计算机上并创建环境变量GOOGLE_APPLICATION_CREDENTIALS

export GOOGLE_APPLICATION_CREDENTIALS=/path/to/keys.json

现在尝试运行你的 python 脚本。

不使用环境变量

您需要安装google-auth python 包，该包提供google.oauth2.service_account 模块，其中有Credentials 类。您可以使用您的凭据初始化此类，如下所示：

from google.oauth2 import service_account

credentials = service_account.Credentials.from_service_account_file(
    '/path/to/keys.json')

然后你可以像这样将这个 credentials 对象传递给 firestore Client()：

db = firestore.Client(credentials=credentials)

【讨论】：