paramikoのexit_status_readyの検証

test.py

# 標準出力とエラー出力をそれぞれ10MiB行うコマンド
#command = '''bash -c 'dd if=/dev/urandom bs=512 count=20480 >&1 & dd if=/dev/urandom bs=512 count=20480 >&2; wait' '''
command = '''bash -c 'cat test.dat >&1 & cat test.dat >&2; wait' '''

import logging
logging.basicConfig()
logging.getLogger("paramiko").setLevel(logging.DEBUG)

import paramiko
client = paramiko.SSHClient()

client.set_missing_host_key_policy(paramiko.MissingHostKeyPolicy()) # 未知の公開鍵の場合は無視
client.connect(hostname="127.0.0.1", port=22, username="test", password="test") # 接続の確立

channel = client.get_transport().open_session(timeout=3) # コマンド実行

try: 
    channel.exec_command(command)
    RECV_SIZE = 1024 * 32
    stdout_data = b''
    stderr_data = b''

    while not channel.exit_status_ready() or channel.recv_ready() or channel.recv_stderr_ready():
        stdout_data += channel.recv(RECV_SIZE)
        channel.recv_stderr(RECV_SIZE)

    # 終了コードを受け取る
    code = channel.recv_exit_status()

    # 色々処理

finally:
    channel.close()

print(f"stdout_data = {len(stdout_data)} byte (expected 10485760 => {len(stdout_data) == 10485760})")
print(f"stderr_data = {len(stderr_data)} byte")

if len(stdout_data) == 10485760:
    exit(0)
else:
    exit(1)

test.sh

while python test.py ; do date; done

失敗時の実行結果(抜粋)

stdout_data = 10470400 byte (expected 10485760 => False)
stderr_data = 10471424 byte