Ghost packaged by Bitnami¶

Ghost is an open source publishing platform designed to create blogs, magazines, and news sites. It includes a simple markdown editor with preview, theming, and SEO built-in to simplify editing.

Overview of Ghost

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

TL;DR¶

使用加速地址添加仓库:

helm repo add bitnami "https://helm-charts.itboon.top/bitnami" --force-update
helm update bitnami

helm install my-release bitnami/ghost

Introduction¶

This chart bootstraps a Ghost deployment on a Kubernetes cluster using the Helm package manager.

It also packages the Bitnami MySQL chart which is required for bootstrapping a MySQL deployment for the database requirements of the Ghost application.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters.

Looking to use Ghost in production? Try VMware Application Catalog, the enterprise edition of Bitnami Application Catalog.

Prerequisites¶

• Kubernetes 1.19+
• Helm 3.2.0+
• PV provisioner support in the underlying infrastructure
• ReadWriteMany volumes for deployment scaling

Installing the Chart¶

To install the chart with the release name my-release:

helm install my-release bitnami/ghost

The command deploys Ghost on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

Uninstalling the Chart¶

To uninstall/delete the my-release deployment:

helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release.

Parameters¶

Global parameters¶

Common parameters¶

Ghost Image parameters¶

Ghost Configuration parameters¶

Ghost deployment parameters¶

Traffic Exposure Parameters¶

Persistence Parameters¶

Database Parameters¶

NetworkPolicy parameters¶

The above parameters map to the env variables defined in bitnami/ghost. For more information please refer to the bitnami/ghost image documentation.

Note:

For the Ghost application function correctly, you should specify the ghostHost parameter to specify the FQDN (recommended) or the public IP address of the Ghost service.

Optionally, you can specify the ghostLoadBalancerIP parameter to assign a reserved IP address to the Ghost service of the chart. However please note that this feature is only available on a few cloud providers (f.e. GKE).

To reserve a public IP address on GKE:

$ gcloud compute addresses create ghost-public-ip

The reserved IP address can be assigned to the Ghost service by specifying it as the value of the service.loadBalancerIP parameter while installing the chart.

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

helm install my-release \
  --set ghostUsername=admin,ghostPassword=password,mysql.auth.rootPassword=secretpassword \
    bitnami/ghost

The above command sets the Ghost administrator account username and password to admin and password respectively. Additionally, it sets the MySQL root user password to secretpassword.

NOTE: Once this chart is deployed, it is not possible to change the application's access credentials, such as usernames or passwords, using Helm. To change these application credentials after deployment, delete any persistent volumes (PVs) used by the chart and re-deploy it, or use the application's built-in administrative tools if available.

Alternatively, a YAML file that specifies the values for the above parameters can be provided while installing the chart. For example,

helm install my-release -f values.yaml bitnami/ghost

Tip: You can use the default values.yaml

Configuration and installation details¶

Rolling VS Immutable tags¶

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

External database support¶

You may want to have Ghost connect to an external database rather than installing one inside your cluster. Typical reasons for this are to use a managed database service, or to share a common database server for all your applications. To achieve this, the chart allows you to specify credentials for an external database with the externalDatabase parameter. You should also disable the MySQL installation with the mysql.enabled option. Here is an example:

mysql.enabled=false
externalDatabase.host=myexternalhost
externalDatabase.user=myuser
externalDatabase.password=mypassword
externalDatabase.database=mydatabase
externalDatabase.port=3306

Refer to the documentation on using an external database with Ghost for more information.

Configure Ingress¶

This chart provides support for Ingress resources. If you have an ingress controller installed on your cluster, such as nginx-ingress-controller or contour you can utilize the ingress controller to serve your application.

To enable Ingress integration, set ingress.enabled to true. The ingress.hostname property can be used to set the host name. The ingress.tls parameter can be used to add the TLS configuration for this host. It is also possible to have more than one host, with a separate TLS configuration for each host. Learn more about configuring and using Ingress.

Configure TLS Secrets for use with Ingress¶

The chart also facilitates the creation of TLS secrets for use with the Ingress controller, with different options for certificate management. Learn more about TLS secrets.

Configure extra environment variables¶

To add extra environment variables (useful for advanced operations like custom init scripts), use the extraEnvVars property.

extraEnvVars:
  - name: LOG_LEVEL
    value: DEBUG

Alternatively, use a ConfigMap or a Secret with the environment variables. To do so, use the extraEnvVarsCM or the extraEnvVarsSecret values.

Configure Sidecars and Init Containers¶

If additional containers are needed in the same pod as Ghost (such as additional metrics or logging exporters), they can be defined using the sidecars parameter. Similarly, you can add extra init containers using the initContainers parameter.

Learn more about configuring and using sidecar and init containers.

Deploy extra resources¶

There are cases where you may want to deploy extra objects, such a ConfigMap containing your app's configuration or some extra deployment with a micro service used by your app. For covering this case, the chart allows adding the full specification of other objects using the extraDeploy parameter.

Set Pod affinity¶

This chart allows you to set custom Pod affinity using the affinity parameter(s). Find more information about Pod affinity in the Kubernetes documentation.

As an alternative, you can use the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common chart. To do so, set the podAffinityPreset, podAntiAffinityPreset, or nodeAffinityPreset parameters.

Persistence¶

The Bitnami Ghost image stores the Ghost data and configurations at the /bitnami/ghost and /bitnami/apache paths of the container.

Persistent Volume Claims are used to keep the data across deployments. This is known to work in GCE, AWS, and minikube. See the Parameters section to configure the PVC or to disable persistence.

Troubleshooting¶

Find more information about how to deal with common errors related to Bitnami's Helm charts in this troubleshooting guide.

Upgrading¶

To 19.0.0¶

This major release changes database management system from MariaDB to MySQL. Since a new DB will be used, you need to create a back up beforehand and restore it in order to keep your data. See the official migration docs.

To 17.0.0¶

This major release bumps the MariaDB version to 10.6. Follow the upstream instructions for upgrading from MariaDB 10.5 to 10.6. No major issues are expected during the upgrade.

To 16.0.0¶

This major release updates the MariaDB subchart to its newest major, 10.0.0. Check MariaDB Upgrading Notes for more information.

To 15.0.0¶

This major release renames several values in this chart and adds missing features, in order to be inline with the rest of assets in the Bitnami charts repository.

Affected values:

• service.port was deprecated, we recommend using service.ports.http instead.
• service.httpsPort was deprecated, we recommend using service.ports.https instead.

To 14.0.0¶

Due to recent changes in the container image (see Notable changes), the major version of the chart has been bumped preemptively.

Compatibility is not guaranteed due to the amount of involved changes, however no breaking changes are expected.

To 12.0.0¶

This version standardizes the way of defining Ingress rules. When configuring a single hostname for the Ingress rule, set the ingress.hostname value. When defining more than one, set the ingress.extraHosts array. Apart from this case, no issues are expected to appear when upgrading.

To 11.0.0¶

In this major there were two main changes introduced:

1. Adaptation to Helm v2 EOL
2. Updated MariaDB dependency version

Please read the update notes carefully.

1. Adaptation to Helm v2 EOL¶

On November 13, 2020, Helm v2 support was formally finished, this major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

What changes were introduced in this major version?¶

• Previous versions of this Helm Chart use apiVersion: v1 (installable by both Helm 2 and 3), this Helm Chart was updated to apiVersion: v2 (installable by Helm 3 only). Here you can find more information about the apiVersion field.
• Move dependency information from the requirements.yaml to the Chart.yaml
• After running helm dependency update, a Chart.lock file is generated containing the same structure used in the previous requirements.lock
• The different fields present in the Chart.yaml file has been ordered alphabetically in a homogeneous way for all the Bitnami Helm Charts

Considerations when upgrading to this version¶

• If you want to upgrade to this version from a previous one installed with Helm v3, you shouldn't face any issues
• If you want to upgrade to this version using Helm v2, this scenario is not supported as this version doesn't support Helm v2 anymore
• If you installed the previous version with Helm v2 and wants to upgrade to this version with Helm v3, please refer to the official Helm documentation about migrating from Helm v2 to v3

Useful links¶

• https://docs.bitnami.com/tutorials/resolve-helm2-helm3-post-migration-issues/
• https://helm.sh/docs/topics/v2_v3_migration/
• https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/

2. Updated MariaDB dependency version**¶

In this major the MariaDB dependency version was also bumped to a new major version that introduces several incompatilibites. Therefore, backwards compatibility is not guaranteed unless an external database is used. Check MariaDB Upgrading Notes for more information.

To upgrade to 11.0.0, it should be done reusing the PVCs used to hold both the MariaDB and Ghost data on your previous release. To do so, follow the instructions below (the following example assumes that the release name is ghost):

NOTE: Please, create a backup of your database before running any of those actions. The steps below would be only valid if your application (e.g. any plugins or custom code) is compatible with MariaDB 10.5.x

Obtain the credentials and the name of the PVC used to hold the MariaDB data on your current release:

export GHOST_HOST=$(kubectl get svc --namespace default ghost --template "{{ range (index .status.loadBalancer.ingress 0) }}{{ . }}{{ end }}")
export GHOST_PASSWORD=$(kubectl get secret --namespace default ghost -o jsonpath="{.data.ghost-password}" | base64 -d)
export MARIADB_ROOT_PASSWORD=$(kubectl get secret --namespace default ghost-mariadb -o jsonpath="{.data.mariadb-root-password}" | base64 -d)
export MARIADB_PASSWORD=$(kubectl get secret --namespace default ghost-mariadb -o jsonpath="{.data.mariadb-password}" | base64 -d)
export MARIADB_PVC=$(kubectl get pvc -l app=mariadb,component=master,release=ghost -o jsonpath="{.items[0].metadata.name}")

Delete the Ghost deployment and delete the MariaDB statefulset. Notice the option --cascade=false in the latter.

kubectl delete deployments.apps ghost

kubectl delete statefulsets.apps ghost-mariadb --cascade=false

Upgrade you release to 11.0.0 reusing the existing PVC, and enabling back MariaDB:

helm upgrade ghost bitnami/ghost --set mariadb.primary.persistence.existingClaim=$MARIADB_PVC --set mariadb.auth.rootPassword=$MARIADB_ROOT_PASSWORD --set mariadb.auth.password=$MARIADB_PASSWORD --set ghostPassword=$GHOST_PASSWORD --set ghostHost=$GHOST_HOST

You will need to kill the existing MariaDB pod now as the new statefulset is going to create a new one:

kubectl delete pod ghost-mariadb-0

You should see the lines below in MariaDB container logs:

$ kubectl logs $(kubectl get pods -l app.kubernetes.io/instance=ghost,app.kubernetes.io/name=mariadb,app.kubernetes.io/component=primary -o jsonpath="{.items[0].metadata.name}")
...
mariadb 12:13:24.98 INFO  ==> Using persisted data
mariadb 12:13:25.01 INFO  ==> Running mysql_upgrade
...

To 10.0.0¶

This version introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

Also, allowEmptyPassword has changed its value type from string to boolean, if you were using it please make sure that you are passing the proper value.

# before
--set allowEmptyPassword="no"
# after
--set allowEmptyPassword=false

To 9.0.0¶

Helm performs a lookup for the object based on its group (apps), version (v1), and kind (Deployment). Also known as its GroupVersionKind, or GVK. Changing the GVK is considered a compatibility breaker from Kubernetes' point of view, so you cannot "upgrade" those objects to the new GVK in-place. Earlier versions of Helm 3 did not perform the lookup correctly which has since been fixed to match the spec.

In https://github.com/helm/charts/pulls/17297 the apiVersion of the deployment resources was updated to apps/v1 in tune with the api's deprecated, resulting in compatibility breakage.

This major version signifies this change.

To 5.0.0¶

Backwards compatibility is not guaranteed unless you modify the labels used on the chart's deployments. Use the workaround below to upgrade from versions previous to 5.0.0. The following example assumes that the release name is ghost:

kubectl patch deployment ghost-ghost --type=json -p='[{"op": "remove", "path": "/spec/selector/matchLabels/chart"}]'
kubectl delete statefulset ghost-mariadb --cascade=false

License¶

Copyright © 2023 VMware, Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.