python-script-for-opening-consoles-and-passing-cmds.py

import pexpect

services = [
    "service-foo", 
    "service-bar",
    ]

def send_cmd_wait_and_catch_timeout(child, cmd, timeout=30):
    try:   

        # Send the cmd
        child.sendline(cmd)

        # Print the output of the cmd
        while True:
            try:
                child.expect('\n', timeout=timeout)  # expect a newline character
                print(child.before)  # print the output before the newline character
            except pexpect.EOF:
                break  # break the loop if End Of File (EOF) is encountered

    except pexpect.exceptions.TIMEOUT:
        print("Timeout occurred")


if __name__ == "__main__": 

    for service in services:

        print('========== processing %s ==========', service)

        # create compass console
        child = pexpect.spawn('compass console run {} -e qa'.format(service))

        # wait for console to be ready 
        while True:
            try:
                child.expect('\n', timeout=120)  # expect a newline character
                if b'try pressing enter' in child.before:
                    break
                print(child.before)  # print the output before the newline character
            except pexpect.EOF:
                break  # break the loop if End Of File (EOF) is encountered

        # test cmd
        # cmd = "psql $POSTGRES_URI -c 'SELECT table_schema,table_name FROM information_schema.tables ORDER BY table_schema,table_name;' | tail"
        cmd = "echo -e 'SELECT NOW();' | bin/rails db -p"
        send_cmd_wait_and_catch_timeout(child, cmd)

        # send a another cmd
        send_cmd_wait_and_catch_timeout(child, cmd)