Symfony4中Redis缓存取消键前缀的配置问题求助

I’ve run into this exact issue before—Symfony’s automatic cache prefixing can be tricky when you need consistent keys across different execution contexts like web requests and Behat tests, even with the same APP_ENV=dev. Let’s break down why your current attempts aren’t working and how to fix it.

Why Your Current Configuration Isn’t Working #

The prefix_seed parameter you’re adjusting is used to generate a base hash for the prefix, but Symfony still adds additional context (like the cache pool name or a hash of your project directory) unless you explicitly override the prefix. Even setting prefix_seed: ~ (null) won’t eliminate the prefix entirely—it just uses a default seed based on your project path, which might differ slightly between your web server’s working directory and Behat’s execution path (that’s why you’re seeing different prefixes like xw+Y6oICD- and gUbUjDoAuQ).

Solution 1: Disable Prefix Entirely #

To completely remove the cache key prefix, you need to explicitly set an empty string for the prefix option in your Redis cache pool configuration. Update your config/packages/framework.yaml like this:

cache:
  prefix_seed: ~ # Optional, since null is the default
  app:
    adapter: cache.adapter.redis
    provider: '%env(resolve:REDIS_URL)%'
    options:
      prefix: '' # This forces empty prefixes

After updating the config, clear your dev cache to apply the changes:

php bin/console cache:clear --env=dev

Solution 2: Use a Fixed Prefix (Recommended for Safety) #

While removing the prefix solves your immediate problem, it’s not the best practice (risk of key collisions with other apps using the same Redis instance). A safer alternative is to set a static, fixed prefix that both your web app and Behat tests will use:

cache:
  app:
    adapter: cache.adapter.redis
    provider: '%env(resolve:REDIS_URL)%'
    options:
      prefix: 'dev_app_cache_' # Fixed prefix for all dev environment keys

This ensures consistent keys across all dev contexts without exposing you to collision risks.

Verify Behat Configuration #

Double-check your behat.yml to ensure it’s using the same APP_ENV=dev and loading the same Symfony configuration. Make sure there’s no override for cache settings in Behat’s context or kernel configuration that might be generating a different prefix.

Test the Fix #

After applying the configuration change and clearing cache:

1. Set a cache key via your web app
2. Run your Behat test that populates the same key
3. Check Redis with keys *—you should see the same key (either without a prefix, or with your fixed prefix) appearing only once, not duplicated with different prefixes.

内容的提问来源于stack exchange，提问作者Pawel