supports JSON logging for gunicorn process within Docker

[AllenSH12]

For #8665

This attempts to bridge the gap between the application and gunicorn config to ensure both are logging in a consistent way.

Before:

$ grep CONSOLE_LOG_LEVEL web/config_local.py
CONSOLE_LOG_LEVEL = logging.INFO

$ grep JSON_LOGGER web/config.py 
JSON_LOGGER = True

$ ./venv/bin/gunicorn  -c ./pkg/docker/gunicorn_config.py --chdir web pgAdmin4:app                                
[2025-05-21 13:20:52 -0400] [36038] [INFO] Starting gunicorn 23.0.0
[2025-05-21 13:20:52 -0400] [36038] [INFO] Listening at: http://127.0.0.1:8000 (36038)
[2025-05-21 13:20:52 -0400] [36038] [INFO] Using worker: sync
[2025-05-21 13:20:52 -0400] [36039] [INFO] Booting worker with pid: 36039
{"time": "2025-05-21 13:20:53,405", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-21 13:20:53,405", "message": "Starting pgAdmin 4 v9.3...", "level": "INFO"}
{"time": "2025-05-21 13:20:53,405", "message": "########################################################", "level": "INFO"}
...

After:

$ grep CONSOLE_LOG_LEVEL web/config_local.py
CONSOLE_LOG_LEVEL = logging.INFO

$ grep JSON_LOGGER web/config.py 
JSON_LOGGER = True

$ ./venv/bin/gunicorn -c ./pkg/docker/gunicorn_config.py --chdir web pgAdmin4:app
[2025-05-21 13:22:30 -0400] [36080] [INFO] Starting gunicorn 23.0.0
{"time": "2025-05-21 13:22:31,529", "message": "Listening at: http://127.0.0.1:8000 (36080)", "level": "INFO"}
{"time": "2025-05-21 13:22:31,529", "message": "Using worker: sync", "level": "INFO"}
{"time": "2025-05-21 13:22:31,532", "message": "Booting worker with pid: 36081", "level": "INFO"}
{"time": "2025-05-21 13:22:31,609", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-21 13:22:31,609", "message": "Starting pgAdmin 4 v9.3...", "level": "INFO"}
{"time": "2025-05-21 13:22:31,610", "message": "########################################################", "level": "INFO"}

And via docker with a locally built image:

$ docker run -d --name=pgadmin4 --rm \
    -e "PGADMIN_DEFAULT_EMAIL=a@b.co" \
    -e "PGADMIN_DEFAULT_PASSWORD=admin" \
    -e "PGADMIN_CONFIG_JSON_LOGGER=True" \
    -e "PGADMIN_CONFIG_CONSOLE_LOG_LEVEL=10" \
    -p 8080:80 \
    allensh12/pgadmin4

$ docker logs -f pgadmin4
...
[2025-05-21 17:24:38 +0000] [1] [INFO] Starting gunicorn 23.0.0
{"time": "2025-05-21 17:24:40,663", "message": "Listening at: http://[::]:80 (1)", "level": "INFO"}
{"time": "2025-05-21 17:24:40,663", "message": "Using worker: gthread", "level": "INFO"}
{"time": "2025-05-21 17:24:40,667", "message": "Booting worker with pid: 121", "level": "INFO"}
{"time": "2025-05-21 17:24:40,876", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-21 17:24:40,876", "message": "Starting pgAdmin 4 v9.3...", "level": "INFO"}
{"time": "2025-05-21 17:24:40,876", "message": "########################################################", "level": "INFO"}

A few outstanding things:

1. The first line from gunicorn ("Starting gunicorn...") does not respect the format, given that this is much less common than access log perhaps that is okay to leave, but I will investigate further.
2. A few other places where printing happens outside of the logger, have marked these with "issues/8665" in the code, can see example below
3. No control over postfix logs, the only one I've seen so far is "postfix/postlog: starting the Postfix mail system" but I have not exercised it more than that. IMO an issue that is worth addressing separately.

$ docker logs -f pgadmin4
email config is {'CHECK_EMAIL_DELIVERABILITY': False, 'ALLOW_SPECIAL_EMAIL_DOMAINS': [], 'GLOBALLY_DELIVERABLE': True}
NOTE: Configuring authentication for SERVER mode.

pgAdmin 4 - Application Initialisation
======================================

postfix/postlog: starting the Postfix mail system
[2025-05-21 17:38:41 +0000] [1] [INFO] Starting gunicorn 23.0.0
{"time": "2025-05-21 17:38:43,326", "message": "Listening at: http://[::]:80 (1)", "level": "INFO"}
{"time": "2025-05-21 17:38:43,327", "message": "Using worker: gthread", "level": "INFO"}
{"time": "2025-05-21 17:38:43,330", "message": "Booting worker with pid: 119", "level": "INFO"}

Curious to hear what y'all think!

[yogeshmahajan-1903]

I guess you have removed changes in the entrypoint.sh while cleaning up the code.

[AllenSH12]

Yes everything is happening in gunicorn_config.py now, makes it easier to share the app config that way but I think there is a better solution still, need to study the Python logging module more

[AllenSH12]

@yogeshmahajan-1903 have this working as desired now, here are some example logs. Can see both gunicorn and pgadmin are logging in JSON, and I created #8801 to follow up with other components, although I have no immediate plans to work on the issue myself.

$ docker run -d --name=pgadmin4 --rm \
    -e "PGADMIN_DEFAULT_EMAIL=a@b.co" \
    -e "PGADMIN_DEFAULT_PASSWORD=admin" \
    -e "PGADMIN_CONFIG_JSON_LOGGER=True" \
    -e "PGADMIN_CONFIG_CONSOLE_LOG_LEVEL=20" \
    -p 8080:80 \
    allensh12/pgadmin4

email config is {'CHECK_EMAIL_DELIVERABILITY': False, 'ALLOW_SPECIAL_EMAIL_DOMAINS': [], 'GLOBALLY_DELIVERABLE': True}
{"time": "2025-05-27 22:20:55,923", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-27 22:20:55,923", "message": "Starting pgAdmin 4 v9.3...", "level": "INFO"}
{"time": "2025-05-27 22:20:55,923", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-27 22:20:56,964", "message": "Registering blueprint module: <AboutModule 'about'>", "level": "INFO"}
{"time": "2025-05-27 22:20:56,964", "message": "Registering blueprint module: <AuthenticateModule 'authenticate'>", "level": "INFO"}
{"time": "2025-05-27 22:20:56,965", "message": "Registering blueprint module: <BrowserModule 'browser'>", "level": "INFO"}
{"time": "2025-05-27 22:20:57,626", "message": "Registering blueprint module: <DashboardModule 'dashboard'>", "level": "INFO"}
{"time": "2025-05-27 22:20:57,634", "message": "Registering blueprint module: <HelpModule 'help'>", "level": "INFO"}
{"time": "2025-05-27 22:20:57,634", "message": "Registering blueprint module: <MiscModule 'misc'>", "level": "INFO"}
{"time": "2025-05-27 22:20:58,340", "message": "Registering blueprint module: <PreferencesModule 'preferences'>", "level": "INFO"}
{"time": "2025-05-27 22:20:58,342", "message": "Registering blueprint module: <PgAdminModule 'redirects'>", "level": "INFO"}
{"time": "2025-05-27 22:20:58,342", "message": "Registering blueprint module: <SettingsModule 'settings'>", "level": "INFO"}
{"time": "2025-05-27 22:20:58,344", "message": "Registering blueprint module: <ToolsModule 'tools'>", "level": "INFO"}
NOTE: Configuring authentication for SERVER mode.

pgAdmin 4 - Application Initialisation
======================================

postfix/postlog: starting the Postfix mail system
guni config True 20 OrderedDict({'time': 'asctime', 'message': 'message', 'level': 'levelname'})
{"time": "2025-05-27 22:21:03,696", "message": "Starting gunicorn 23.0.0", "level": "INFO"}
{"time": "2025-05-27 22:21:03,697", "message": "Listening at: http://[::]:80 (1)", "level": "INFO"}
{"time": "2025-05-27 22:21:03,697", "message": "Using worker: gthread", "level": "INFO"}
{"time": "2025-05-27 22:21:03,700", "message": "Booting worker with pid: 121", "level": "INFO"}
{"time": "2025-05-27 22:21:03,907", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-27 22:21:03,908", "message": "Starting pgAdmin 4 v9.3...", "level": "INFO"}
{"time": "2025-05-27 22:21:03,908", "message": "########################################################", "level": "INFO"}
{"time": "2025-05-27 22:21:04,570", "message": "Registering blueprint module: <AboutModule 'about'>", "level": "INFO"}
{"time": "2025-05-27 22:21:04,570", "message": "Registering blueprint module: <AuthenticateModule 'authenticate'>", "level": "INFO"}
{"time": "2025-05-27 22:21:04,571", "message": "Registering blueprint module: <BrowserModule 'browser'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,297", "message": "Registering blueprint module: <DashboardModule 'dashboard'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,305", "message": "Registering blueprint module: <HelpModule 'help'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,306", "message": "Registering blueprint module: <MiscModule 'misc'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,992", "message": "Registering blueprint module: <PreferencesModule 'preferences'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,993", "message": "Registering blueprint module: <PgAdminModule 'redirects'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,994", "message": "Registering blueprint module: <SettingsModule 'settings'>", "level": "INFO"}
{"time": "2025-05-27 22:21:05,995", "message": "Registering blueprint module: <ToolsModule 'tools'>", "level": "INFO"}
{"time": "2025-05-27 22:21:18,001", "message": "::ffff:172.17.0.1 - - [27/May/2025:22:21:18 +0000] \"GET / HTTP/1.1\" 302 213 \"-\" \"curl/8.7.1\"", "level": "INFO"}

[AllenSH12]

Thank you @akshay-joshi!