Advanced Usage

Queue Management

Building Images

Images are built either:

  1. Via cron job running build_img_queue
  2. Or via task runner using the queued_img signal

Manual Queueing

Queue images manually using the queue method:

from easy_images import Img
from my_app.models import Product

thumbnail = Img(width=300)
thumbnail.queue(Product, fields=['main_image'])

Automatic Queueing

Automatically queue images when a FileField is saved using signals: 

from django.apps import AppConfig
from my_app.images import thumbnail

class MyAppConfig(AppConfig):
    def ready(self):
        from my_app.models import Profile
        thumbnail.queue(Profile, build="src")

Performance Tips

  1. For high-traffic sites, use build="src" to generate base images immediately
  2. Set up Celery for distributed image processing
  3. Use format="webp" for best compression/performance balance
  4. Limit densities to [2] unless high-DPI support is critical (or turn it off entirely)
  5. Consider pre-generating common image sizes during deployment

Signals

file_post_save

Triggered when a FileField is saved. Use to automatically queue images:

from django.apps import AppConfig
from my_app.images import thumbnail

class MyAppConfig(AppConfig):
    def ready(self):
        from my_app.models import Profile
        thumbnail.queue(Profile, build="src")

queued_img

Triggered when images need building. Use with Celery:

from easy_images.management.process_queue import process_queue
from easy_images.signals import queued_img

@app.task
def build_img_queue():
    process_queue()

# In apps.py:
queued_img.connect(lambda **kwargs: build_img_queue.delay(), weak=False)