Help:Toolforge/Redis for Toolforge

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This page contains information about Redis for Toolforge.

Redis for Toolforge

Redis, is a key-value store that can be used to implement publish/subscribe protocols between processes and maintain persistent queues. Stored values can be different data structures, such as hash tables, lists, queues, etc. Stored data persists across service restarts.

Redis instances

A Redis instance that can be used by all tools is available via the service name, on the standard port 6379. It has been allocated a maximum of 12G of memory, which should be enough for most usage. You can set limits for how long your data stays in Redis; otherwise it will be evicted when memory limits are exceeded. See the Redis documentation for a list of available commands.

Redis libraries

Libraries for interacting with Redis from PHP (phpredis), Python (redis-py), and Perl (perl-redis) are installed on all the bastions and grid engine nodes. For an example of a bot using Redis, see gerrit-to-redis.

For quick & dirty debugging, you can connect directly to the Redis server with nc -C 6379 and execute commands (for example "INFO") or using redis-cli (also installed on the grid-engine nodes) redis-cli -h


The redis service can be used as a broker between the worker and the web frontend to run a celery worker in a kubernetes container, as continuous job, see the documentation for Kubernetes (for instance to execute long-running tasks triggered by a web frontend).

If using Django, assuming you use following definition of the namespace in your file:

app.config_from_object('django.conf:settings', namespace='CELERY')

Then, you can adapt the as following:


REDIS_URL = ':%s@%s:%s/%d' % (

CELERY_DEFAULT_QUEUE = "your-tool-name.default"  # Change 'your-tool-name'

The deployment file for Kubernetes to start the worker can be written as (see Kubernetes#Kubernetes_continuous_jobs):

And the script for starting celery ( can have following form:

/data/project/your-tool-name/www/python/venv/bin/celery -A yourDjangoApp worker

Of course, if your virtual environment is at a different position, adapt the path.

To start your worker, type:

kubectl create --validate=true -f $HOME/www/python/src/deployment.yml

If everything is fine, "kubectl logs" followed from the name of the created pods should display typical celery starting feedback.


Redis has no access control mechanism, so other users can accidentally/intentionally overwrite and access the keys you set. Even if you are not worried about security, it is highly probable that multiple tools will try to use the same key (such as lastupdated, etc). To prevent this, it is highly recommended that you prefix all your keys with an application-specific, lengthy, randomly generated secret key.

PLEASE PREFIX YOUR KEYS! We have also disabled the Redis commands that let users 'list' keys. This protection however should not be trusted to protect any secret data. Do not store plain text secrets or decryption keys in Redis for your own protection.

You can generate a prefix by running the following command:

openssl rand -base64 32

Disabled Redis commands

Some built-in Redis commands have been disabled in an attempt to Redis safer for multi-tenant usage:

  • KEYS
  • SCAN

See Also

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