supervisord-on-action

This repository contains the following:

1. Simple Flask Python App.
2. Simple Supervisor configuration.
3. Simple Python command line to control service run by Supervisor using XML-RPC interface.

Prerequisites

In order to be able to run the code on this repository, the following items are needed:

1. Python3
2. pip
3. Unix-Like Operation System (Centos, Mac, RedHat, Ubuntu)

Installation & Setup

1. Clone this repository git clone https://github.com/mabuaisha/supervisord-on-action.git
2. Create virtualenv python3 -m venv supervisor-env.
3. Activate virtualenv source supervisor-env/bin/activate.
4. Install Python packages using pip pip install -r requirement.txt.

Running Program using Supervisor

1. Copy supervisord-on-action repository under /opt.
2. Run supervisord main process supervisord -n -c /opt/supervisord-on-action/app.conf &.
3. Now, the gunicorn process should be started and the Hello World app should be up and running http://0.0.0.0:5000.

Using Supervisorctl Client

supervisorctl is the command line allows you to control services run by supervisord

1. Get the status of service supervisorctl -c /opt/supervisord-on-action/app.conf status simple-app.
2. Stop service supervisorctl -c /opt/supervisord-on-action/app.conf stop simple-app.
3. Start service supervisorctl -c /opt/supervisord-on-action/app.conf start simple-app.

Controlling Supervisor using XML-RPC interface

parse.py is a simple command line allows you to control services managed by supervisor using XML-RPC.

(supervisor-env) ➜  supervisord-on-action git:(master) ✗ python3 parse.py --help
usage: parse.py [-h] -a ACTION -p PROCESS_NAME

Simple arg parser for supervisor command

optional arguments:
  -h, --help       show this help message and exit
  -a ACTION        Store action value
  -p PROCESS_NAME  Store process name

It accepts two parameters which are:

1. -a: Action we need to execute on the service managed by supervisor. currently only start/stop is supported for this command.
2. -p: Process name we need to control and execute action.

(supervisor-env) ➜  supervisord-on-action git:(master) ✗ python parse.py -a stop -p simple-app
2020-10-14 22:48:17,617 DEBG killing simple-app (pid 30222) with signal SIGTERM
2020-10-14 22:48:17,617 INFO waiting for simple-app to stop
2020-10-14 22:48:17,619 DEBG 'simple-app' stderr output:
[2020-10-14 22:48:17 +0300] [30222] [INFO] Handling signal: term

2020-10-14 22:48:17,620 DEBG 'simple-app' stderr output:
[2020-10-14 22:48:17 +0300] [30225] [INFO] Worker exiting (pid: 30225)

2020-10-14 22:48:17,724 DEBG 'simple-app' stderr output:
[2020-10-14 22:48:17 +0300] [30222] [INFO] Shutting down: Master

2020-10-14 22:48:17,764 DEBG fd 13 closed, stopped monitoring <POutputDispatcher at 4386817752 for <Subprocess at 4385315304 with name simple-app in state STOPPING> (stderr)>
2020-10-14 22:48:17,764 DEBG fd 11 closed, stopped monitoring <POutputDispatcher at 4386817080 for <Subprocess at 4385315304 with name simple-app in state STOPPING> (stdout)>
2020-10-14 22:48:17,764 INFO stopped: simple-app (exit status 0)
2020-10-14 22:48:17,764 DEBG received SIGCHLD indicating a child quit
stop simple-app executed successfully