PM2.js to Run Gunicorn/Flask App inside Virtualenv/Anaconda env

Question

I have been running gunicorn to serve a Python Flask app using the commands

conda activate fooenv
gunicorn --workers=4 -b 0.0.0.0:5000 --worker-class=meinheld.gmeinheld.MeinheldWorker api.app:app 

How can we use pm2 instead to run gunicorn/flask app inside the fooenv environment?

Answer 1

supposed you can run gunicorn in your venv via e.g.:

gunicorn wsgi:app -b localhost:5010

then you simply use command (in the venv):

pm2 --name=myapp start "gunicorn wsgi:app -b localhost:5010"

(took me way too long to figure this out btw)

Answer 2

I would create a pm2.json file in the same directory as your app, then start it with pm2 start pm2.json. pm2 ls will now show your app running.

{
    "apps": [
      {
        "name": "my-app",
        "script": "gunicorn --workers=4 -b 0.0.0.0:5000 --worker-class=meinheld.gmeinheld.MeinheldWorker api.app:app",
        "watch": false,
        "max_memory_restart": "256M",
        "output": "/var/www/html/logs/my-app-out.log",
        "error": "/var/www/html/logs/my-app-error.log",
        "kill_timeout": 5000,
        "restartDelay": 5000
      }
    ]
  }