arq-prometheus

Arq-prometheus

Prometheus metrics for arq

⚠️ WARNING! This is a project in alpha phase ⚠️

Installation

Pip

pip install -U arq-prometheus

Poetry

poetry add arq-prometheus

Description

The metrics exposed are the same as the health check.

Metric name	Description
arq_jobs_completed	The number of jobs completed
arq_jobs_failed	The total number of errored jobs
arq_jobs_retried	The total number of retried jobs
arq_ongoing_jobs	The number of jobs in progress
arq_queued_inprogress	The number of jobs in progress

When working with arq I found some limitations, it was specially hard to get access to the worker in order to retrieve information like the queue_name or health_check_key. The startup and shutdown functions only make available a ctx with the redis connection. This means that if you provide a custom queue_name or health_check_key, you will also have to provide them to ArqPrometheusMetrics.

Usage

# example_worker.py
from arq_prometheus import ArqPrometheusMetrics

async def startup(ctx):
    arq_prometheus = ArqPrometheusMetrics(ctx, delay=delay)
    ctx["arq_prometheus"] = await arq_prometheus.start()

async def shutdown(ctx):
    await ctx["arq_prometheus"].stop()

class WorkerSettings:
    on_startup = startup
    on_shutdown = shutdown
    function = []  # your arq jobs
    ... # other settings

Start your arq worker,

arq example_worker.WorkerSettings

Make request to localhost:8081 (or open in browser).

curl localhost:8081

Arguments

• ctx: dict: arq context
• queue_name: str = default_queue_name: name of the arq queue
• health_check_key: Optional[str] = None: arq health key
• delay: datetime.timedelta = datetime.timedelta(seconds=5): a datetime.timedelta
• enable_webserver: bool = True: set to True if you want a web server exposing the metrics
• addr: str = "0.0.0.0": webserver address
• port: int = 8081: webserver port
• registry: prom.CollectorRegistry = prom.REGISTRY: the prometheus registry, usually you do not have to override this