Being able to check currently live/unfinished requests

[bentcoder]

Hi,

I think it would be nicer if I use an example scenario.

Assume that I run a command that checks if there is currently a live request being processed in the app (obviously the response hasn't been returned yet). If the app is free from requests then run some logic. Otherwise wait for all existing requests to be finished first.

Same time the command should prevent new requests coming in otherwise the logic will probably never run in very busy apps.

Does this make sense?

Thanks

[javiereguiluz]

At first sight this looks like a too specific feature to be included in the Symfony core. Also, there should be already alternative ways of implementing this:

• If you want to run something after some deploy and before the new requests arrive, there are deployment techniques that allow you tu run commands before/during/after deployment and before enabling the new deployed version.
• If it's about "locking" access to resources to prevent other requests from changing/accessing what your console command is editing/generating, you can use the Lock component: https://symfony.com/doc/current/components/lock.html

[bentcoder]

Much appreciated with your response. My exact case is this:

1. I deploy a dockerised Symfony app - (nginx, mysql and php-fpm as containers).
2. Before running the doctrine:migration:migrate command in php-fpm container, I want all current requests be finished first.
3. Once there is no request, run the doctrine:migration:migrate command.

The reason why I am actually asking this is because, there will be cases I'll be renaming existing tables in DB which would be problem if there was live requests that depend on old table name.

What is your suggestion on this? If there is a solution for this, could you please direct me to the resource?

Thanks

[maartendekeizer]

Sent a gracefull shutdown command to Nginx. After Nginx stopt theire are no active connections left and you can safely run your migration. When using other load ballancing software it is also possible to use thinks like connection draining.

[fabpot]

This really depends on your hosting platform. Nothing generic we can do in Symfony itself. So closing.