rq_workers and rq_jobs metrics are empty when checked in Prometheus

[mobilego]

rq_workers and rq_jobs metrics are empty when checked in Prometheus. I could see the output for rq_request_processing_seconds_count this metric. All the jobs and workers are under a specific namespace under database 0. Should we specify the namespace in the url RQ_REDIS_URL ? Could you please let me know what could be the reason for workers and jobs metrics are empty ?

[mdawar]

Hi,

By namespace you mean the Queue.redis_queue_namespace_prefix and Worker.redis_worker_namespace_prefix class variables right? Are you using a custom Queue and Worker classes? And what about the Job class are you using a custom namespace too?

You cannot specify this namespace using the Redis URL.

The reason these metrics are empty because we're using the default Queue and Worker classes to fetch the data so we're using the default namespace prefix.

I'll start working on this, if you have any suggestions please let me know.

[mdawar]

I have added support for specifying custom RQ Worker and Queue classes which solves your problem if you're using custom namespace prefixes, these changes were released under a new version 1.3.0, feel free to re-open this issue if it doesn't solve your problem.

[mobilego]

Appreciate you quick response. I have workers under 127.0.0.1:6379> keys "prod:worker:" and multiple queues under 127.0.0.1:6379> keys "prod:queue1:" 127.0.0.1:6379> keys "prod:queue2:*" . How should i specify RQ_WORKER_CLASS and RQ_QUEUE_CLASS ? Could you please help ?

[mdawar]

I've assumed that you're using custom Worker and Queue classes where you can change the namespace prefixes, for example:

from rq import Worker, Queue
from rq.job import Job

class CustomJob(Job):
    redis_job_namespace_prefix = 'rq:custom:job:'

class CustomQueue(Queue):
    redis_queue_namespace_prefix = 'rq:custom:queue:'
    job_class = CustomJob

class CustomWorker(Worker):
    redis_worker_namespace_prefix = 'rq:custom:worker:'
    queue_class = CustomQueue
    job_class = CustomJob

So you can configure rq-exporter to use these classes instead of the default rq.Queue and rq.Worker classes using these configuration options:

CLI Argument	Env Variable	Default Value	Description
--worker-class	RQ_WORKER_CLASS	rq.Worker	RQ worker class
--queue-class	RQ_QUEUE_CLASS	rq.Queue	RQ queue class

For example I've added a docker-compose.custom.yml file that contains an example on how to do this:

rq_exporter:
    image: mdawar/rq-exporter:latest
    # You can also configure the exporter using command line options
    # command: |
    #   --redis-host redis
    #   --redis-pass-file /run/secrets/redis_pass
    #   --worker-class 'custom.CustomWorker'
    #   --queue-class 'custom.CustomQueue'
    ports:
      - target: 9726
        published: 9726
        protocol: tcp
        mode: host
    environment:
      # Redis configuration
      RQ_REDIS_HOST: "redis"
      RQ_REDIS_PASS_FILE: /run/secrets/redis_pass
      RQ_REDIS_DB: "0"
      # Add the project's path to be able to import the classes
      # Escaping the $ sign is only needed only in the `docker-compose.yml` file
      PYTHONPATH: "$${PYTHONPATH}:/home/project"
      RQ_WORKER_CLASS: "custom.CustomWorker"
      RQ_QUEUE_CLASS: "custom.CustomQueue"
    volumes:
      # Mount your project where you define the custom classes
      - type: bind
        source: ./docker-compose/project
        target: /home/project

Of course you don't have to be using Docker nor docker-compose to do this but this gives you an idea on how to configure the exporter.