Google Cloud Datastore Emulator 不使用默认凭据

Question

根据Google's Cloud Datastore Emulator installation instructions，我能够在bash 终端窗口中安装和运行模拟器，而gcloud beta emulators datastore start --project gramm-id 没有问题。

我还在另一个带有$(gcloud beta emulators datastore env-init) 的终端中设置了环境变量per the instructions，并验证了它们已被定义。

但是，当我运行我的 python 脚本以使用以下代码将实体添加到本地数据存储时：

from google.cloud import datastore

print(os.environ['DATASTORE_HOST'])          # output: http://localhost:8081
print(os.environ['DATASTORE_EMULATOR_HOST']) # output: localhost:8081


client = datastore.Client('gramm-id')
kind = 'Task'
name = 'simpleTask'

task_key = client.key(kind, name)
task = client.Enity(key=task_key)
task['description'] = 'Buy milk'
client.put(task)

我得到错误：

Traceback (most recent call last):
  File "tools.py", line 237, in <module>
    client = datastore.Client('gramm-id')
  File "/home/.../lib/python3.6/site-packages/google/cloud/datastore/client.py", line 205, in __init__
    project=project, credentials=credentials, _http=_http)
... long stack trace ....
  File "/home/.../lib/python3.6/site-packages/google/auth/_default.py", line 306, 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://developers.google.com/accounts/docs/application-default-credentials.

我认为我不需要 create a GCP service account and provide access credentials 在我的机器上使用数据存储模拟器。

我的系统：

• Ubuntu 18.04
• Anaconda python 3.6.6
• 谷歌云 SDK 215.0.0
• 云数据存储模拟器 2.0.2。

我错过了什么？

Answer 1

理论上您应该能够使用模拟凭据，例如：

class EmulatorCreds(google.auth.credentials.Credentials):

    def __init__(self):
        self.token = b'secret'
        self.expiry = None

    @property
    def valid(self):
        return True

    def refresh(self, _):
        raise RuntimeError('Should never be refreshed.')

client = datastore.Client(
    project='gramm-id',
    credentials=EmulatorCreds() , 
    _http=requests.Session()  # Un-authorized
)

但是it seems like this doesn't currently work，所以现在你需要设置GOOGLE_APPLICATION_CREDENTIALS

Answer 2

gcloud auth 应用程序-默认登录

这将提示您通过浏览器窗口登录，并为您正确设置 GOOGLE_APPLICATION_CREDENTIALS。 [1]