Loki
- Canonical Observability
Channel | Revision | Published | Runs on |
---|---|---|---|
latest/stable | 160 | 10 Sep 2024 | |
latest/candidate | 161 | 19 Nov 2024 | |
latest/beta | 177 | 19 Nov 2024 | |
latest/edge | 181 | 30 Nov 2024 | |
1.0/stable | 104 | 12 Dec 2023 | |
1.0/candidate | 104 | 22 Nov 2023 | |
1.0/beta | 104 | 22 Nov 2023 | |
1.0/edge | 104 | 22 Nov 2023 |
juju deploy loki-k8s --channel 1.0/stable
Deploy Kubernetes operators easily with Juju, the Universal Operator Lifecycle Manager. Need a Kubernetes cluster? Install MicroK8s to create a full CNCF-certified Kubernetes system in under 60 seconds.
Platform:
Logging via Pebble Log Forwarding
You can easily integrate with the Loki charm to send the logs of the workload via Pebble’s log forwarding feature. This allows you to gather the logs that your workload is printing to stdout
and send them to Loki.
If your workload doesn’t produce logs to stdout, you can add a Pebble service that runs
tail -f /path/to/log.file
to achieve the same result.
Prepare your charm
To start, fetch the loki_push_api
charm library:
charmcraft fetch-lib charms.loki_k8s.v1.loki_push_api
Add an integration to your charm for the loki_push_api
interface, in metadata.yaml
(or charmcraft.yaml
, if you use the single-file structure):
requires:
logging: # recommended name, but you can change it
interface: loki_push_api
description: |
Receives Loki's push api endpoint address to push logs to, and forwards charm's built-in alert rules to Loki.
Write the integration code
The loki_push_api
library provides a Log Forwarder
object that conveniently wraps all the necessary things you would need to write. Internally, this objects updates the Pebble layer’s log-targets
section with the correct Juju Topology information (e.g., application name, unit name, etc.).
Use the Log Forwarder
class by instantiating it in the __init__
method of your charm:
from charms.loki_k8s.v1.loki_push_api import LogForwarder
def __init__(self, *args):
...
self._log_forwarder = LogForwarder(
self,
relation_name="logging", # optional, defaults to "logging"
)
The Log Forwarder
will, by default, observe relation events on the logging
endpoint and enable (or disable) log forwarding automatically.
Test the result
You can now deploy your charm and try to relate it to Loki:
juju deploy <your-charm>
juju deploy loki-k8s loki
juju relate <your-charm> loki
Once the relation is active and healthy, the library will inject a Pebble layer in each workload container the charm has access to, to configure Pebble’s log forwarding and start sending logs to Loki.