# ------------------------------------
# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.
# ------------------------------------
import asyncio
import sys
import os
from typing import TYPE_CHECKING
from azure.core.exceptions import ClientAuthenticationError
from .._internal import AsyncContextManager
from .._internal.decorators import log_get_token_async
from ... import CredentialUnavailableError
from ..._credentials.azure_cli import (
AzureCliCredential as _SyncAzureCliCredential,
CLI_NOT_FOUND,
COMMAND_LINE,
get_safe_working_dir,
NOT_LOGGED_IN,
parse_token,
sanitize_output,
)
from ..._internal import _scopes_to_resource
if TYPE_CHECKING:
from typing import Any
from azure.core.credentials import AccessToken
[docs]class AzureCliCredential(AsyncContextManager):
"""Authenticates by requesting a token from the Azure CLI.
This requires previously logging in to Azure via "az login", and will use the CLI's currently logged in identity.
"""
[docs] @log_get_token_async
async def get_token(self, *scopes: str, **kwargs: "Any") -> "AccessToken":
"""Request an access token for `scopes`.
This method is called automatically by Azure SDK clients. Applications calling this method directly must
also handle token caching because this credential doesn't cache the tokens it acquires.
:param str scopes: desired scope for the access token. This credential allows only one scope per request.
:rtype: :class:`azure.core.credentials.AccessToken`
:raises ~azure.identity.CredentialUnavailableError: the credential was unable to invoke the Azure CLI.
:raises ~azure.core.exceptions.ClientAuthenticationError: the credential invoked the Azure CLI but didn't
receive an access token.
"""
# only ProactorEventLoop supports subprocesses on Windows (and it isn't the default loop on Python < 3.8)
if sys.platform.startswith("win") and not isinstance(asyncio.get_event_loop(), asyncio.ProactorEventLoop):
return _SyncAzureCliCredential().get_token(*scopes, **kwargs)
resource = _scopes_to_resource(*scopes)
output = await _run_command(COMMAND_LINE.format(resource))
token = parse_token(output)
if not token:
sanitized_output = sanitize_output(output)
raise ClientAuthenticationError(message="Unexpected output from Azure CLI: '{}'".format(sanitized_output))
return token
[docs] async def close(self):
"""Calling this method is unnecessary"""
async def _run_command(command: str) -> str:
if sys.platform.startswith("win"):
args = ("cmd", "/c " + command)
else:
args = ("/bin/sh", "-c", command)
working_directory = get_safe_working_dir()
try:
proc = await asyncio.create_subprocess_exec(
*args,
stdout=asyncio.subprocess.PIPE,
stderr=asyncio.subprocess.STDOUT,
cwd=working_directory,
env=dict(os.environ, AZURE_CORE_NO_COLOR="true")
)
stdout, _ = await asyncio.wait_for(proc.communicate(), 10)
output = stdout.decode()
except OSError as ex:
# failed to execute 'cmd' or '/bin/sh'; CLI may or may not be installed
error = CredentialUnavailableError(message="Failed to execute '{}'".format(args[0]))
raise error from ex
except asyncio.TimeoutError as ex:
proc.kill()
raise CredentialUnavailableError(message="Timed out waiting for Azure CLI") from ex
if proc.returncode == 0:
return output
if proc.returncode == 127 or output.startswith("'az' is not recognized"):
raise CredentialUnavailableError(CLI_NOT_FOUND)
if "az login" in output or "az account set" in output:
raise CredentialUnavailableError(message=NOT_LOGGED_IN)
message = sanitize_output(output) if output else "Failed to invoke Azure CLI"
raise ClientAuthenticationError(message=message)