README

A Firestore-backed session driver for Laravel, designed to run smoothly on Google App Engine (Standard environment).

Installation

composer require firevel/firestore-session-driver

Configuration

1) Set the session driver

App Engine (app.yaml):

env_variables:
  SESSION_DRIVER: firestore
  # Optional: tune GC batch size (see "Garbage collection & scale")
  # SESSION_GC_BATCH_SIZE: 500

Local development (.env):

SESSION_DRIVER=firestore
# SESSION_GC_BATCH_SIZE=500

Firestore credentials on App Engine Standard are picked up via Application Default Credentials. For local development, set GOOGLE_APPLICATION_CREDENTIALS if needed.

2) (Optional) Session lifetime

Configure the session lifetime as usual in config/session.php or via .env:

SESSION_LIFETIME=120

Garbage collection & scale

Firestore session cleanup happens via Laravel’s session lottery. On very high-traffic apps this can be a bottleneck. You can tune or offload it:

• Adjust the lottery in config/session.php (note the correct path/key):

  'lottery' => [2, 100], // e.g., 2% chance per request

• Batch size: control how many expired sessions are removed per GC pass:

  SESSION_GC_BATCH_SIZE=500

• Heavy load / HA setups: consider moving GC out of request flow. Run cleanup on a schedule (cron/Scheduler) and set a very low lottery, or temporarily switch to the cookie driver if GC becomes a hotspot.

In extreme cases, run garbage collection from a scheduled job/cron and reduce the in-request lottery to near zero.

Limitations

• Review Firestore’s quotas and limits before deploying high-throughput workloads: https://cloud.google.com/firestore/quotas