For any problems with this charm, please report bugs here.
The code for this charm can be downloaded as follows:
git clone https://github.com/canonical/redis-k8s
Setup, build and deploy
A typical setup using snaps, for deployments to a microk8s cluster can be done using the following commands.
Install the dependencies:
sudo snap install juju --classic
sudo snap install microk8s --classic
microk8s.enable dns hostpath-storage
Create a controller named micro into the cloud microk8s:
juju bootstrap microk8s micro
In Juju, you interact with the client (the juju command on your local machine).
It connects to a controller. The controller is hosted on a cloud and controls models.
juju add-model redis-model
Then you build and deploy this charm into the model you just created:
charmcraft pack
juju deploy ./redis-k8s_ubuntu-20.04-amd64.charm --resource redis-image=dataplatformoci/redis:7.0-22.04_edge
Once Redis starts up it will be running on its default port, 6379. To check it you run:
juju status
to discover the IP Redis is running behind. The output will have lines like:
Unit Workload Agent Address Ports Message
redis-k8s/0* active idle 10.1.168.69
To retrieve the password to access the database, use the get-initial-admin-password action:
juju run-action redis-k8s/0 get-initial-admin-password --wait
Then, from your local machine, you can:
redis-cli -h 10.1.168.69 -p 6379 -a <password>
Another option is to port-forward the Redis pod or service port from k8s to a local port. For example, forwarding a node’s port
microk8s.kubectl --namespace=redis-model port-forward pod/redis-8485b69dfd-6hgvj 6379:6379
However, it is simpler to forward the service port as it will abstract the node name behind it:
microk8s.kubectl --namespace=redis-model port-forward service/redis 6379:6379
Then you can simply:
redis-cli
From a k8s non-charmed scenario Redis will be exposed as Service named redis on the default
port 6379.
Developing
The charm is based on the operator framework. Create and activate a tox virtual environment with the development requirements:
virtualenv -p python3 venv
source venv/bin/activate
pip install -r requirements.txt
In order to check the result of a modification, rebuild and upgrade the charm:
# Consider now that you are inside redis-k8s directory.
charmcraft pack
juju upgrade-charm --path="./redis-k8s_ubuntu-20.04-amd64.charm" redis-k8s --force-units
Or you can clean up things on different levels, application, model, and controller:
juju remove-application redis-k8s --force --no-wait
juju destroy-model redis-model --destroy-storage --force --no-wait
juju destroy-controller micro --destroy-all-models
Debugging
In order to enable TRACE level at the unit to make everything shows:
juju model-config logging-config="<root>=WARNING;unit=TRACE"
To show the logs for a specific mode:
juju debug-log -m redis-model
To show the logs for all the units in the model:
microk8s.kubectl get all --namespace=redis-model
To see the logs for a specific pod:
microk8s.kubectl --namespace=redis-model logs redis-k8s-0
Testing
The Python operator framework includes a very nice harness for testing operator behaviour without full deployment.
tox -e fmt # update your code according to linting rules
tox -e lint # code style
tox -e unit # unit tests
tox -e integration # integration tests
tox # runs 'lint' and 'unit' environments
Canonical Contributor Agreement
Canonical welcomes contributions to the Charmed Redis Operator. Please check out our contributor agreement if you’re interested in contributing to the solution.