Moodle LMS - Deployment Guide.

Steps to deploy Moodle LMS via docker-compose and Kubernetes. Uses branch 404_STABLE Uses Docker base image moodlehq/moodle-docker.

Docker-Compose

1. Update the .env file appropriately. Please note that we are using v3 compose files which do not use .env files by default. Instead, docker-compose.yml sources the .env file into the microservices manually.

2. Deploy. This builds the image locally.

docker-compose up -d

Kubernetes

Requisites (run only once)

Context

1. Source envfile

source ./k8s/overlays/prod/.env

2. Create dedicated namespace for Moodle and a Kubernetes app instance for customer eg. fhcgr. These are interpolated by envsubst in the Kustomize templates.

export \
  NAMESPACE=tess \
  INSTANCE=fhcgr \
  TAG=latest 


kubectl create namespace $NAMESPACE

Database

Moodle install script requires ready database instance on your kubernetes cluster. in the database namespace.

Supported database engines in externalDatabase.type are: mysqli, mariadb, pgsql, auroramysql Hints below for MariaDB and PostgreSQL.

MariaDB Secrets

1. Copy existing MariaDB secrets from the "database" namespace to this project,

kubectl -n database get secrets/mariadb -o yaml | \
  yq 'del(.metadata.creationTimestamp, .metadata.uid, .metadata.resourceVersion, .metadata.namespace)' | \
  kubectl apply -n $NAMESPACE -f -

Nota: We will use above created secrets/mysql in place of mariadb.mariadbRootPassword. This will be referenced use by the externalDatabase.existingSecret config below. Subsequently, in chart config, reference existing mysql database resp. to its namespace ie. mysql.database.

2. Create the database

# Forward pgpool service to localhost:5432
kubectl -n database port-forward svc/mariadb 3306:3306

# Connect to MariaDB as user "root"
DB_PASSWORD=$(kubectl -n database  get secrets/mariadb -o jsonpath="{.data.mariadb-root-password}" | base64 -d)
mysql -u root -p$DB_PASSWORD -h localhost

# Then, in MySQL shell, run:
# create database fhcgr_moodle;

PostgreSQL Secrets

1. Obtain DB_HOST, DB_PORT, DB_USER, DB_PASSWORD for your existing db instance.

Note that we do NOT use the DB_PASSWORD env. In this particular setting, the db root password is pulled manually a Secret resource existing in our production cluster and injected into the $NAMESPACE namespace using a ConfigMap.

Eg., following example extracts existing PostgreSQL db secret from our database namespace, and injects it into the moodle namespace. Nota: our root db_username defaults to postgres.

kubectl -n database get secrets/pgpool -o yaml | \
  yq 'del(.metadata.creationTimestamp, .metadata.uid, .metadata.resourceVersion, .metadata.namespace)' | \
  kubectl apply -n $NAMESPACE -f -

2. Create database in PostgreSQL

kubectl -n database port-forward svc/pg-pgpool 5432

# Connect to PostgreSQL as user "root"
DB_PASSWORD=kubectl -n database  get secrets/mariadb -o jsonpath="{.data.mariadb-root-password}" | base64 -d
psql postgresql://$DB_USER:$DB_PASSWORD@localhost:5432 "create database "$DB_NAME" encoding utf8;"

Container image

Build and push the image to my private DockerHub

docker build ./docker -t ceduth/moodle:$TAG \
  && docker push ceduth/moodle:$TAG

Deploy

Follow up with additional steps for GKE if applies.

This setup uses Kustomize layere-based configuration management.

By default deploys and exposes Moodle behind a Nginx ingress controller pre-installed on GKE. Check for instructions to setup a Nginx Ingress Controller with CertManager that provisions TLS certificates for an entire cluster.

1. Set your .env file appropriately in directory docker-moodle/k8s/. Note, we have set SSL_PROXY=true in the env file since we seat behind Nginx Ingress proxy.

2. Create Moodle user and email

kubectl -n $NAMESPACE create secret/fhcgr-moodle  \
  --from-literal=moodle-password='Th3P@ssw0rd!' \
  --from-literal=moodle-email='francois.carvalho.alvarenga@gmail.com' 

3. From moodle-k8s directory, run: Nota: This creates an internal service resource, reachable only within the cluster.

# kubectl apply -n $NAMESPACE -k ./k8s/overlays/prod
~/DevOps/bin/kustomize build ./k8s/overlays/prod | envsubst | kubectl -n $NAMESPACE apply -f -

4. Create an ExternalName resource in the default namespace, that point to the internal moodle service in namespace designated namespace.

cat <<EOF | envsubst | kubectl apply -n $NAMESPACE -f -
kind: Service
apiVersion: v1
metadata:
  name: fhcgr-moodle
spec:
  type: ExternalName
  externalName: moodle.$NAMESPACE
EOF

5. Finally merge following rule that routes https traffic into existing Nginx Ingress configuration:

---
kind: Ingress
apiVersion: networking.k8s.io/v1
metadata:
  name: web-ingress
  annotations:
    kubernetes.io/ingress-class: nginx
    cert-manager.io/cluster-issuer: letsencrypt-prod

...

# <THE-UPDATE>
spec:
  tls:
  ...
  rules:
  - host: "fc.echq.online"
    http:
      paths:
      - pathType: Prefix
        path: "/"
        backend:
          service:
            name: moodle
            port:
              number: 80
# </THE-UPDATE>

6. Point your browser at: https://<MOODLE_URL> Note: MOODLE_URL was previously set in our env file.

Optional steps

• Fix moodle version in database (did'nt work for me!)

# Get version from the git repo at
# Or copy version from running pod via ssh at /var/www/html/version.php
# Or fetch it from https://moodledev.io/general/releases
# Cf. https://stackoverflow.com/a/32208453/4615806
# eg. 2022041912.00 for MOODLE_404_STABLE
# --
# Worth reading, but did'nt work for me!
# https://docs.moodle.org/404/en/Installation_FAQ#"Could_not_find_a_top_level_course"
INSERT INTO mdl_config (name, value) VALUES ('version', '2022041912');

• Run the installer manually

Refs: here and there

Follow the wizard. Choose /var/moodledata when asked for Moodle data dir (cf. Dockerfile)

su www-data -c 'php admin/cli/install.php --agree-license' -s /bin/bash
su www-data -c 'php admin/cli/install_database.php --agree-license --adminpass=Th3P@ssw0rd!' -s /bin/bash

• Check php info

# Create info.php in public dir, then
# Open https://fc.echq.online/info.php in brnowser
cat << EOF > /var/www/html/info.php
<?php
    phpinfo();
?>
EOF

Cleanup

kubectl -n tess delete deployment/fhcgr-moodle
kubectl -n tess delete pvc/fhcgr-moodle-pvc

Resources

• kustomize-with-multiple-envs

https://github.com/kubernetes-sigs/kustomize/blob/master/examples/secretGeneratorPlugin.md

https://kubernetes.io/docs/tasks/configmap-secret/managing-secret-using-kustomize