hash_password accepts stdin now (#17608)

`hash_password` now actually accepts password from stdin. The `getpass`
reads from TTY, and does NOT accept stdin in any way.

The manpage has been updated to reflect that.

1 files changed, 3 insertions, 1 deletions

diff --git a/synapse/_scripts/hash_password.py b/synapse/_scripts/hash_password.py

index 3bed367be2..2b7d3585cb 100755
--- a/synapse/_scripts/hash_password.py
+++ b/synapse/_scripts/hash_password.py
@@ -56,7 +56,9 @@ def main() -> None:
     password_pepper = password_config.get("pepper", password_pepper)
     password = args.password
 
-    if not password:
+    if not password and not sys.stdin.isatty():
+        password = sys.stdin.readline().strip()
+    elif not password:
         password = prompt_for_pass()
 
     # On Python 2, make sure we decode it to Unicode before we normalise it