[Identity] Suppress stdin for subprocess-based creds (#31534)

In some cases, the underyling executable being called
hangs waiting for user input. When calling the executables
we should just ignore stdin.

Signed-off-by: Paul Van Eck <paulvaneck@microsoft.com>

Author: pvaneck

sdk/identity/azure-identity/CHANGELOG.md

@@ -9,6 +9,7 @@
 ### Bugs Fixed
 
 - Ensure `AzurePowershellCredential` calls PowerShell with the `-NoProfile` flag to avoid loading user profiles for more consistent behavior.  ([#31682](https://github.com/Azure/azure-sdk-for-python/pull/31682))
+- Fixed an issue with subprocess-based developer credentials (such as AzureCliCredential) where the process would sometimes hang waiting for user input.  ([#31534](https://github.com/Azure/azure-sdk-for-python/pull/31534))
 
 ### Other Changes
 

sdk/identity/azure-identity/azure/identity/_credentials/azd_cli.py

@@ -211,6 +211,7 @@ def _run_command(command: str, timeout: int) -> str:
 
         kwargs: Dict[str, Any] = {
             "stderr": subprocess.PIPE,
+            "stdin": subprocess.DEVNULL,
             "cwd": working_directory,
             "universal_newlines": True,
             "env": dict(os.environ, NO_COLOR="true"),

sdk/identity/azure-identity/azure/identity/_credentials/azure_cli.py

@@ -187,6 +187,7 @@ def _run_command(command: str, timeout: int) -> str:
 
         kwargs: Dict[str, Any] = {
             "stderr": subprocess.PIPE,
+            "stdin": subprocess.DEVNULL,
             "cwd": working_directory,
             "universal_newlines": True,
             "timeout": timeout,

sdk/identity/azure-identity/azure/identity/_credentials/azure_powershell.py

@@ -158,6 +158,7 @@ def start_process(args: List[str]) -> "subprocess.Popen":
         cwd=working_directory,
         stdout=subprocess.PIPE,
         stderr=subprocess.PIPE,
+        stdin=subprocess.DEVNULL,
         universal_newlines=True,
     )
     return proc

sdk/identity/azure-identity/azure/identity/aio/_credentials/azd_cli.py

@@ -158,6 +158,7 @@ async def _run_command(command: str, timeout: int) -> str:
             *args,
             stdout=asyncio.subprocess.PIPE,
             stderr=asyncio.subprocess.PIPE,
+            stdin=asyncio.subprocess.DEVNULL,
             cwd=working_directory,
             env=dict(os.environ, NO_COLOR="true"),
         )

sdk/identity/azure-identity/azure/identity/aio/_credentials/azure_cli.py

@@ -136,6 +136,7 @@ async def _run_command(command: str, timeout: int) -> str:
             *args,
             stdout=asyncio.subprocess.PIPE,
             stderr=asyncio.subprocess.PIPE,
+            stdin=asyncio.subprocess.DEVNULL,
             cwd=working_directory,
             env=dict(os.environ, AZURE_CORE_NO_COLOR="true"),
         )

sdk/identity/azure-identity/azure/identity/aio/_credentials/azure_powershell.py

@@ -139,5 +139,6 @@ async def start_process(command_line):
         cwd=working_directory,
         stdout=asyncio.subprocess.PIPE,
         stderr=asyncio.subprocess.PIPE,
+        stdin=asyncio.subprocess.DEVNULL,
     )
     return proc