PromucFlow_constructor/deploy/docker/scripts/starting-page-init.py
Sumesh Pradhan a359444556
fix: improve starting page removal script with error handling (#23392)
- Removed event listener python script, removed supervisor conf for the
same.
- Added new python script to handle the starting page init.
- Python script will be called via a shell script with a failsafe
removal of the loading page.
- The above shell script will be run as a child of the run java script

Tests:
The child script exits after execution, and does not create zombie
process even when the run java script is called multiple times with
restarts.
Verified exceptions and failsafe manually by introducing syntax errors
and uninstalling requests module.

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Co-authored-by: Shrikant Sharat Kandula <shrikant@appsmith.com>
2023-06-06 18:32:40 +05:30

81 lines
2.3 KiB
Python

import os
import sys
import time
import shutil
import subprocess
import logging
import traceback
import atexit
LOADING_TEMPLATE_PAGE = r'/opt/appsmith/templates/appsmith_starting.html'
LOADING_PAGE_EDITOR = r'/opt/appsmith/editor/loading.html'
BACKEND_HEALTH_ENDPOINT = "http://localhost:8080/api/v1/health"
LOG_FILE = r'/appsmith-stacks/logs/backend/starting_page_init.log'
LOG_FORMAT = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
logging.basicConfig(filename = LOG_FILE, level = logging.NOTSET, format = LOG_FORMAT)
try:
import requests
except ModuleNotFoundError as e:
logging.error("Module Not Found: " , e)
def get_backend_status():
try:
return subprocess.getoutput("supervisorctl status backend").split()[1]
except subprocess.CalledProcessError as e:
logging.error("Subprocess Error ", e)
except ValueError as e:
logging.error("Value Error ", e)
def check_health_endpoint(url,sleep_sec = 3,timeout_sec = 180):
for _ in range(timeout_sec//sleep_sec):
try:
if requests.get(url).ok:
logging.info('Backend health check successful.')
break
except ImportError as e:
logging.error("Import Error: ", e)
sys.exit(1)
except requests.RequestException:
pass # retry after sleep_sec
finally:
time.sleep(sleep_sec)
if get_backend_status() in ('FATAL' , 'BACKOFF'):
break
else:
logging.error('Timeout Error: Backend health check timeout.')
def remove_loading_page():
retries = 3
for _ in range(retries):
try:
if os.path.exists(LOADING_PAGE_EDITOR):
os.remove(LOADING_PAGE_EDITOR)
break
except OSError as e:
logging.error("Failed to remove loading page ", e)
time.sleep(1)
else:
logging.error("Loading page removal failed after %i retries. Trying again one final time.", retries)
logging.info(subprocess.getoutput("rm -fv " + LOADING_PAGE_EDITOR))
def add_loading_page():
shutil.copyfile(LOADING_TEMPLATE_PAGE, LOADING_PAGE_EDITOR)
@atexit.register
def failsafe():
remove_loading_page()
def main():
add_loading_page()
check_health_endpoint(BACKEND_HEALTH_ENDPOINT)
remove_loading_page()
if __name__ == '__main__':
main()