- Generating a cluster service version (CSV)
- Understanding your custom resource definitions (CRDs)
- Understanding your API services
Generating a cluster service version (CSV)
A cluster service version (CSV), defined by a ClusterServiceVersion
object, is a YAML manifest created from Operator metadata that assists Operator Lifecycle Manager (OLM) in running the Operator in a cluster. It is the metadata that accompanies an Operator container image, used to populate user interfaces with information such as its logo, description, and version. It is also a source of technical information that is required to run the Operator, like the RBAC rules it requires and which custom resources (CRs) it manages or depends on.
The Operator SDK includes the generate csv
subcommand to generate a CSV for the current Operator project customized using information contained in manually-defined YAML manifests and Operator source files.
A CSV-generating command removes the responsibility of Operator authors having in-depth OLM knowledge in order for their Operator to interact with OLM or publish metadata to the Catalog Registry. Further, because the CSV spec will likely change over time as new Kubernetes and OLM features are implemented, the Operator SDK is equipped to easily extend its update system to handle new CSV features going forward.
The CSV version is the same as the Operator version, and a new CSV is generated when upgrading Operator versions. Operator authors can use the --csv-version
flag to have their Operator state encapsulated in a CSV with the supplied semantic version:
$ operator-sdk generate csv --csv-version <version>
This action is idempotent and only updates the CSV file when a new version is supplied, or a YAML manifest or source file is changed. Operator authors should not have to directly modify most fields in a CSV manifest. Those that require modification are defined in this guide. For example, the CSV version must be included in metadata.name
.
How CSV generation works
The deploy/
directory of an Operator project is the standard location for all manifests required to deploy an Operator. The Operator SDK can use data from manifests in deploy/
to write a cluster service version (CSV).
The following command:
$ operator-sdk generate csv --csv-version <version>
writes a CSV YAML file to the deploy/olm-catalog/
directory by default.
Exactly three types of manifests are required to generate a CSV:
operator.yaml
*_{crd,cr}.yaml
RBAC role files, for example
role.yaml
Operator authors may have different versioning requirements for these files and can configure which specific files are included in the deploy/olm-catalog/csv-config.yaml
file.
Workflow
Depending on whether an existing CSV is detected, and assuming all configuration defaults are used, the generate csv
subcommand either:
Creates a new CSV, with the same location and naming convention as exists currently, using available data in YAML manifests and source files.
The update mechanism checks for an existing CSV in
deploy/
. When one is not found, it creates aClusterServiceVersion
object, referred to here as a cache, and populates fields easily derived from Operator metadata, such as Kubernetes APIObjectMeta
.The update mechanism searches
deploy/
for manifests that contain data a CSV uses, such as aDeployment
resource, and sets the appropriate CSV fields in the cache with this data.After the search completes, every cache field populated is written back to a CSV YAML file.
or:
Updates an existing CSV at the currently pre-defined location, using available data in YAML manifests and source files.
The update mechanism checks for an existing CSV in
deploy/
. When one is found, the CSV YAML file contents are marshaled into a CSV cache.The update mechanism searches
deploy/
for manifests that contain data a CSV uses, such as aDeployment
resource, and sets the appropriate CSV fields in the cache with this data.After the search completes, every cache field populated is written back to a CSV YAML file.
Individual YAML fields are overwritten and not the entire file, as descriptions and other non-generated parts of a CSV should be preserved. |
CSV composition configuration
Operator authors can configure CSV composition by populating several fields in the deploy/olm-catalog/csv-config.yaml
file:
Field | Description |
---|---|
| The Operator resource manifest file path. Default: |
| A list of CRD and CR manifest file paths. Default: |
| A list of RBAC role manifest file paths. Default: |
Manually-defined CSV fields
Many CSV fields cannot be populated using generated, generic manifests that are not specific to Operator SDK. These fields are mostly human-written metadata about the Operator and various custom resource definitions (CRDs).
Operator authors must directly modify their cluster service version (CSV) YAML file, adding personalized data to the following required fields. The Operator SDK gives a warning during CSV generation when a lack of data in any of the required fields is detected.
The following tables detail which manually-defined CSV fields are required and which are optional.
Field | Description |
---|---|
| A unique name for this CSV. Operator version should be included in the name to ensure uniqueness, for example |
| The capability level according to the Operator maturity model. Options include |
| A public name to identify the Operator. |
| A short description of the functionality of the Operator. |
| Keywords describing the Operator. |
| Human or organizational entities maintaining the Operator, with a |
| The provider of the Operator (usually an organization), with a |
| Key-value pairs to be used by Operator internals. |
| Semantic version of the Operator, for example |
| Any CRDs the Operator uses. This field is populated automatically by the Operator SDK if any CRD YAML files are present in
|
Field | Description |
---|---|
| The name of the CSV being replaced by this CSV. |
| URLs (for example, websites and documentation) pertaining to the Operator or application being managed, each with a |
| Selectors by which the Operator can pair resources in a cluster. |
| A base64-encoded icon unique to the Operator, set in a |
| The level of maturity the software has achieved at this version. Options include |
Further details on what data each field above should hold are found in the CSV spec.
Several YAML fields currently requiring user intervention can potentially be parsed from Operator code. |
Additional resources
Operator metadata annotations
Operator developers can manually define certain annotations in the metadata of a cluster service version (CSV) to enable features or highlight capabilities in user interfaces (UIs), such as OperatorHub.
The following table lists Operator metadata annotations that can be manually defined using metadata.annotations
fields.
Field | Description | ||
---|---|---|---|
| Provide custom resource definition (CRD) templates with a minimum set of configuration. Compatible UIs pre-fill this template for users to further customize. | ||
| Specify a single required custom resource that must be created at the time that the Operator is installed. Must include a template that contains a complete YAML definition. | ||
| Set a suggested namespace where the Operator should be deployed. | ||
| Infrastructure features supported by the Operator. Users can view and filter by these features when discovering Operators through OperatorHub in the web console. Valid, case-sensitive values:
| ||
| Free-form array for listing any specific subscriptions that are required to use the Operator. For example, | ||
| Hides CRDs in the UI that are not meant for user manipulation. |
Example use cases
Operator supports disconnected and proxy-aware
operators.openshift.io/infrastructure-features: '["disconnected", "proxy-aware"]'
Operator requires an OpenShift Container Platform license
operators.openshift.io/valid-subscription: '["OpenShift Container Platform"]'
Operator requires a 3scale license
operators.openshift.io/valid-subscription: '["3Scale Commercial License", "Red Hat Managed Integration"]'
Operator supports disconnected and proxy-aware, and requires an OpenShift Container Platform license
operators.openshift.io/infrastructure-features: '["disconnected", "proxy-aware"]'
operators.openshift.io/valid-subscription: '["OpenShift Container Platform"]'
Additional resources
Enabling your Operator for restricted network environments (disconnected mode)
Generating a CSV
Prerequisites
- An Operator project generated using the Operator SDK
Procedure
In your Operator project, configure your CSV composition by modifying the
deploy/olm-catalog/csv-config.yaml
file, if desired.Generate the CSV:
$ operator-sdk generate csv --csv-version <version>
In the new CSV generated in the
deploy/olm-catalog/
directory, ensure all required, manually-defined fields are set appropriately.
Enabling your Operator for restricted network environments
As an Operator author, your Operator must meet additional requirements to run properly in a restricted network, or disconnected, environment.
Operator requirements for supporting disconnected mode
In the cluster service version (CSV) of your Operator:
List any related images, or other container images that your Operator might require to perform their functions.
Reference all specified images by a digest (SHA) and not by a tag.
All dependencies of your Operator must also support running in a disconnected mode.
Your Operator must not require any off-cluster resources.
For the CSV requirements, you can make the following changes as the Operator author.
Prerequisites
- An Operator project with a CSV.
Procedure
Use SHA references to related images in two places in the CSV for your Operator:
Update
spec.relatedImages
:...
spec:
relatedImages: (1)
- name: etcd-operator (2)
image: quay.io/etcd-operator/operator@sha256:d134a9865524c29fcf75bbc4469013bc38d8a15cb5f41acfddb6b9e492f556e4 (3)
- name: etcd-image
image: quay.io/etcd-operator/etcd@sha256:13348c15263bd8838ec1d5fc4550ede9860fcbb0f843e48cbccec07810eebb68
...
1 Create a relatedImages
section and set the list of related images.2 Specify a unique identifier for the image. 3 Specify each image by a digest (SHA), not by an image tag. Update the
env
section in the deployment when declaring environment variables that inject the image that the Operator should use:spec:
install:
spec:
deployments:
- name: etcd-operator-v3.1.1
spec:
replicas: 1
selector:
matchLabels:
name: etcd-operator
strategy:
type: Recreate
template:
metadata:
labels:
name: etcd-operator
spec:
containers:
- args:
- /opt/etcd/bin/etcd_operator_run.sh
env:
- name: WATCH_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.annotations['olm.targetNamespaces']
- name: ETCD_OPERATOR_DEFAULT_ETCD_IMAGE (1)
value: quay.io/etcd-operator/etcd@sha256:13348c15263bd8838ec1d5fc4550ede9860fcbb0f843e48cbccec07810eebb68 (2)
- name: ETCD_LOG_LEVEL
value: INFO
image: quay.io/etcd-operator/operator@sha256:d134a9865524c29fcf75bbc4469013bc38d8a15cb5f41acfddb6b9e492f556e4 (3)
imagePullPolicy: IfNotPresent
livenessProbe:
httpGet:
path: /healthy
port: 8080
initialDelaySeconds: 10
periodSeconds: 30
name: etcd-operator
readinessProbe:
httpGet:
path: /ready
port: 8080
initialDelaySeconds: 10
periodSeconds: 30
resources: {}
serviceAccountName: etcd-operator
strategy: deployment
1 Inject the images referenced by the Operator by using environment variables. 2 Specify each image by a digest (SHA), not by an image tag. 3 Also reference the Operator container image by a digest (SHA), not by an image tag. When configuring probes, the
timeoutSeconds
value must be lower than theperiodSeconds
value. ThetimeoutSeconds
default value is1
. TheperiodSeconds
default value is10
.
Add the
disconnected
annotation, which indicates that the Operator works in a disconnected environment:metadata:
annotations:
operators.openshift.io/infrastructure-features: '["disconnected"]'
Operators can be filtered in OperatorHub by this infrastructure feature.
Enabling your Operator for multiple architectures and operating systems
Operator Lifecycle Manager (OLM) assumes that all Operators run on Linux hosts. However, as an Operator author, you can specify whether your Operator supports managing workloads on other architectures, if worker nodes are available in the OKD cluster.
If your Operator supports variants other than AMD64 and Linux, you can add labels to the cluster service version (CSV) that provides the Operator to list the supported variants. Labels indicating supported architectures and operating systems are defined by the following:
labels:
operatorframework.io/arch.<arch>: supported (1)
operatorframework.io/os.<os>: supported (2)
1 | Set <arch> to a supported string. |
2 | Set <os> to a supported string. |
Only the labels on the channel head of the default channel are considered for filtering package manifests by label. This means, for example, that providing an additional architecture for an Operator in the non-default channel is possible, but that architecture is not available for filtering in the |
If a CSV does not include an os
label, it is treated as if it has the following Linux support label by default:
labels:
operatorframework.io/os.linux: supported
If a CSV does not include an arch
label, it is treated as if it has the following AMD64 support label by default:
labels:
operatorframework.io/arch.amd64: supported
If an Operator supports multiple node architectures or operating systems, you can add multiple labels, as well.
Prerequisites
An Operator project with a CSV.
To support listing multiple architectures and operating systems, your Operator image referenced in the CSV must be a manifest list image.
For the Operator to work properly in restricted network, or disconnected, environments, the image referenced must also be specified using a digest (SHA) and not by a tag.
Procedure
Add a label in the
metadata.labels
of your CSV for each supported architecture and operating system that your Operator supports:labels:
operatorframework.io/arch.s390x: supported
operatorframework.io/os.zos: supported
operatorframework.io/os.linux: supported (1)
operatorframework.io/arch.amd64: supported (1)
1 After you add a new architecture or operating system, you must also now include the default os.linux
andarch.amd64
variants explicitly.
Additional resources
- See the Image Manifest V 2, Schema 2 specification for more information on manifest lists.
Architecture and operating system support for Operators
The following strings are supported in Operator Lifecycle Manager (OLM) on OKD when labeling or filtering Operators that support multiple architectures and operating systems:
Architecture | String |
---|---|
AMD64 |
|
64-bit PowerPC little-endian |
|
IBM Z |
|
Operating system | String |
---|---|
Linux |
|
z/OS |
|
Different versions of OKD and other Kubernetes-based distributions might support a different set of architectures and operating systems. |
Setting a suggested namespace
Some Operators must be deployed in a specific namespace, or with ancillary resources in specific namespaces, in order to work properly. If resolved from a subscription, Operator Lifecycle Manager (OLM) defaults the namespaced resources of an Operator to the namespace of its subscription.
As an Operator author, you can instead express a desired target namespace as part of your cluster service version (CSV) to maintain control over the final namespaces of the resources installed for their Operators. When adding the Operator to a cluster using OperatorHub, this enables the web console to autopopulate the suggested namespace for the cluster administrator during the installation process.
Procedure
In your CSV, set the
operatorframework.io/suggested-namespace
annotation to your suggested namespace:metadata:
annotations:
operatorframework.io/suggested-namespace: <namespace> (1)
1 Set your suggested namespace.
Defining webhooks
Webhooks allow Operator authors to intercept, modify, and accept or reject resources before they are saved to the object store and handled by the Operator controller. Operator Lifecycle Manager (OLM) can manage the lifecycle of these webhooks when they are shipped alongside your Operator.
The cluster service version (CSV) resource of an Operator can include a webhookdefinitions
section to define the following types of webhooks:
Admission webhooks (validating and mutating)
Conversion webhooks
Procedure
Add a
webhookdefinitions
section to thespec
section of the CSV of your Operator and include any webhook definitions using atype
ofValidatingAdmissionWebhook
,MutatingAdmissionWebhook
, orConversionWebhook
. The following example contains all three types of webhooks:CSV containing webhooks
apiVersion: operators.coreos.com/v1alpha1
kind: ClusterServiceVersion
metadata:
name: webhook-operator.v0.0.1
spec:
customresourcedefinitions:
owned:
- kind: WebhookTest
name: webhooktests.webhook.operators.coreos.io (1)
version: v1
install:
spec:
deployments:
- name: webhook-operator-webhook
...
...
...
strategy: deployment
installModes:
- supported: false
type: OwnNamespace
- supported: false
type: SingleNamespace
- supported: false
type: MultiNamespace
- supported: true
type: AllNamespaces
webhookdefinitions:
- type: ValidatingAdmissionWebhook (2)
admissionReviewVersions:
- v1beta1
- v1
containerPort: 443
targetPort: 4343
deploymentName: webhook-operator-webhook
failurePolicy: Fail
generateName: vwebhooktest.kb.io
rules:
- apiGroups:
- webhook.operators.coreos.io
apiVersions:
- v1
operations:
- CREATE
- UPDATE
resources:
- webhooktests
sideEffects: None
webhookPath: /validate-webhook-operators-coreos-io-v1-webhooktest
- type: MutatingAdmissionWebhook (3)
admissionReviewVersions:
- v1beta1
- v1
containerPort: 443
targetPort: 4343
deploymentName: webhook-operator-webhook
failurePolicy: Fail
generateName: mwebhooktest.kb.io
rules:
- apiGroups:
- webhook.operators.coreos.io
apiVersions:
- v1
operations:
- CREATE
- UPDATE
resources:
- webhooktests
sideEffects: None
webhookPath: /mutate-webhook-operators-coreos-io-v1-webhooktest
- type: ConversionWebhook (4)
admissionReviewVersions:
- v1beta1
- v1
containerPort: 443
targetPort: 4343
deploymentName: webhook-operator-webhook
generateName: cwebhooktest.kb.io
sideEffects: None
webhookPath: /convert
conversionCRDs:
- webhooktests.webhook.operators.coreos.io (5)
...
1 The CRDs targeted by the conversion webhook must exist here. 2 A validating admission webhook. 3 A mutating admission webhook. 4 A conversion webhook. 5 The spec.PreserveUnknownFields
property of each CRD must be set tofalse
ornil
.
Additional resources
Kubernetes documentation:
Webhook considerations for OLM
When deploying an Operator with webhooks using Operator Lifecycle Manager (OLM), you must define the following:
The
type
field must be set to eitherValidatingAdmissionWebhook
,MutatingAdmissionWebhook
, orConversionWebhook
, or the CSV will be placed in a failed phase.The CSV must contain a deployment whose name is equivalent to the value supplied in the
deploymentName
field of thewebhookdefinition
.
When the webhook is created, OLM ensures that the webhook only acts upon namespaces that match the Operator group that the Operator is deployed in.
Certificate authority constraints
OLM is configured to provide each deployment with a single certificate authority (CA). The logic that generates and mounts the CA into the deployment was originally used by the API service lifecycle logic. As a result:
The TLS certificate file is mounted to the deployment at
/apiserver.local.config/certificates/apiserver.crt
.The TLS key file is mounted to the deployment at
/apiserver.local.config/certificates/apiserver.key
.
Admission webhook rules constraints
To prevent an Operator from configuring the cluster into an unrecoverable state, OLM places the CSV in the failed phase if the rules defined in an admission webhook intercept any of the following requests:
Requests that target all groups
Requests that target the
operators.coreos.com
groupRequests that target the
ValidatingWebhookConfigurations
orMutatingWebhookConfigurations
resources
Conversion webhook constraints
OLM places the CSV in the failed phase if a conversion webhook definition does not adhere to the following constraints:
CSVs featuring a conversion webhook can only support the
AllNamespaces
install mode.The CRD targeted by the conversion webhook must have its
spec.preserveUnknownFields
field set tofalse
ornil
.The conversion webhook defined in the CSV must target an owned CRD.
There can only be one conversion webhook on the entire cluster for a given CRD.
Understanding your custom resource definitions (CRDs)
There are two types of custom resource definitions (CRDs) that your Operator can use: ones that are owned by it and ones that it depends on, which are required.
Owned CRDs
The custom resource definitions (CRDs) owned by your Operator are the most important part of your CSV. This establishes the link between your Operator and the required RBAC rules, dependency management, and other Kubernetes concepts.
It is common for your Operator to use multiple CRDs to link together concepts, such as top-level database configuration in one object and a representation of replica sets in another. Each one should be listed out in the CSV file.
Field | Description | Required/optional |
---|---|---|
| The full name of your CRD. | Required |
| The version of that object API. | Required |
| The machine readable name of your CRD. | Required |
| A human readable version of your CRD name, for example | Required |
| A short description of how this CRD is used by the Operator or a description of the functionality provided by the CRD. | Required |
| The API group that this CRD belongs to, for example | Optional |
| Your CRDs own one or more types of Kubernetes objects. These are listed in the It is recommended to only list out the objects that are important to a human, not an exhaustive list of everything you orchestrate. For example, do not list config maps that store internal state that are not meant to be modified by a user. | Optional |
| These descriptors are a way to hint UIs with certain inputs or outputs of your Operator that are most important to an end user. If your CRD contains the name of a secret or config map that the user must provide, you can specify that here. These items are linked and highlighted in compatible UIs. There are three types of descriptors:
All descriptors accept the following fields:
Also see the openshift/console project for more information on Descriptors in general. | Optional |
The following example depicts a MongoDB Standalone
CRD that requires some user input in the form of a secret and config map, and orchestrates services, stateful sets, pods and config maps:
Example owned CRD
- displayName: MongoDB Standalone
group: mongodb.com
kind: MongoDbStandalone
name: mongodbstandalones.mongodb.com
resources:
- kind: Service
name: ''
version: v1
- kind: StatefulSet
name: ''
version: v1beta2
- kind: Pod
name: ''
version: v1
- kind: ConfigMap
name: ''
version: v1
specDescriptors:
- description: Credentials for Ops Manager or Cloud Manager.
displayName: Credentials
path: credentials
x-descriptors:
- 'urn:alm:descriptor:com.tectonic.ui:selector:core:v1:Secret'
- description: Project this deployment belongs to.
displayName: Project
path: project
x-descriptors:
- 'urn:alm:descriptor:com.tectonic.ui:selector:core:v1:ConfigMap'
- description: MongoDB version to be installed.
displayName: Version
path: version
x-descriptors:
- 'urn:alm:descriptor:com.tectonic.ui:label'
statusDescriptors:
- description: The status of each of the pods for the MongoDB cluster.
displayName: Pod Status
path: pods
x-descriptors:
- 'urn:alm:descriptor:com.tectonic.ui:podStatuses'
version: v1
description: >-
MongoDB Deployment consisting of only one host. No replication of
data.
Required CRDs
Relying on other required CRDs is completely optional and only exists to reduce the scope of individual Operators and provide a way to compose multiple Operators together to solve an end-to-end use case.
An example of this is an Operator that might set up an application and install an etcd cluster (from an etcd Operator) to use for distributed locking and a Postgres database (from a Postgres Operator) for data storage.
Operator Lifecycle Manager (OLM) checks against the available CRDs and Operators in the cluster to fulfill these requirements. If suitable versions are found, the Operators are started within the desired namespace and a service account created for each Operator to create, watch, and modify the Kubernetes resources required.
Field | Description | Required/optional |
---|---|---|
| The full name of the CRD you require. | Required |
| The version of that object API. | Required |
| The Kubernetes object kind. | Required |
| A human readable version of the CRD. | Required |
| A summary of how the component fits in your larger architecture. | Required |
Example required CRD
required:
- name: etcdclusters.etcd.database.coreos.com
version: v1beta2
kind: EtcdCluster
displayName: etcd Cluster
description: Represents a cluster of etcd nodes.
CRD upgrades
OLM upgrades a custom resource definition (CRD) immediately if it is owned by a singular cluster service version (CSV). If a CRD is owned by multiple CSVs, then the CRD is upgraded when it has satisfied all of the following backward compatible conditions:
All existing serving versions in the current CRD are present in the new CRD.
All existing instances, or custom resources, that are associated with the serving versions of the CRD are valid when validated against the validation schema of the new CRD.
Adding a new CRD version
Procedure
To add a new version of a CRD to your Operator:
Add a new entry in the CRD resource under the
versions
section of your CSV.For example, if the current CRD has a version
v1alpha1
and you want to add a new versionv1beta1
and mark it as the new storage version, add a new entry forv1beta1
:versions:
- name: v1alpha1
served: true
storage: false
- name: v1beta1 (1)
served: true
storage: true
1 New entry. Ensure the referencing version of the CRD in the
owned
section of your CSV is updated if the CSV intends to use the new version:customresourcedefinitions:
owned:
- name: cluster.example.com
version: v1beta1 (1)
kind: cluster
displayName: Cluster
1 Update the version
.Push the updated CRD and CSV to your bundle.
Deprecating or removing a CRD version
Operator Lifecycle Manager (OLM) does not allow a serving version of a custom resource definition (CRD) to be removed right away. Instead, a deprecated version of the CRD must be first disabled by setting the served
field in the CRD to false
. Then, the non-serving version can be removed on the subsequent CRD upgrade.
Procedure
To deprecate and remove a specific version of a CRD:
Mark the deprecated version as non-serving to indicate this version is no longer in use and may be removed in a subsequent upgrade. For example:
versions:
- name: v1alpha1
served: false (1)
storage: true
1 Set to false
.Switch the
storage
version to a serving version if the version to be deprecated is currently thestorage
version. For example:versions:
- name: v1alpha1
served: false
storage: false (1)
- name: v1beta1
served: true
storage: true (1)
1 Update the storage
fields accordingly.In order to remove a specific version that is or was the
storage
version from a CRD, that version must be removed from thestoredVersion
in the status of the CRD. OLM will attempt to do this for you if it detects a stored version no longer exists in the new CRD.Upgrade the CRD with the above changes.
In subsequent upgrade cycles, the non-serving version can be removed completely from the CRD. For example:
versions:
- name: v1beta1
served: true
storage: true
Ensure the referencing CRD version in the
owned
section of your CSV is updated accordingly if that version is removed from the CRD.
CRD templates
Users of your Operator must be made aware of which options are required versus optional. You can provide templates for each of your custom resource definitions (CRDs) with a minimum set of configuration as an annotation named alm-examples
. Compatible UIs will pre-fill this template for users to further customize.
The annotation consists of a list of the kind, for example, the CRD name and the corresponding metadata
and spec
of the Kubernetes object.
The following full example provides templates for EtcdCluster
, EtcdBackup
and EtcdRestore
:
metadata:
annotations:
alm-examples: >-
[{"apiVersion":"etcd.database.coreos.com/v1beta2","kind":"EtcdCluster","metadata":{"name":"example","namespace":"default"},"spec":{"size":3,"version":"3.2.13"}},{"apiVersion":"etcd.database.coreos.com/v1beta2","kind":"EtcdRestore","metadata":{"name":"example-etcd-cluster"},"spec":{"etcdCluster":{"name":"example-etcd-cluster"},"backupStorageType":"S3","s3":{"path":"<full-s3-path>","awsSecret":"<aws-secret>"}}},{"apiVersion":"etcd.database.coreos.com/v1beta2","kind":"EtcdBackup","metadata":{"name":"example-etcd-cluster-backup"},"spec":{"etcdEndpoints":["<etcd-cluster-endpoints>"],"storageType":"S3","s3":{"path":"<full-s3-path>","awsSecret":"<aws-secret>"}}}]
Hiding internal objects
It is common practice for Operators to use custom resource definitions (CRDs) internally to accomplish a task. These objects are not meant for users to manipulate and can be confusing to users of the Operator. For example, a database Operator might have a Replication
CRD that is created whenever a user creates a Database object with replication: true
.
As an Operator author, you can hide any CRDs in the user interface that are not meant for user manipulation by adding the operators.operatorframework.io/internal-objects
annotation to the cluster service version (CSV) of your Operator.
Procedure
Before marking one of your CRDs as internal, ensure that any debugging information or configuration that might be required to manage the application is reflected on the status or
spec
block of your CR, if applicable to your Operator.Add the
operators.operatorframework.io/internal-objects
annotation to the CSV of your Operator to specify any internal objects to hide in the user interface:Internal object annotation
apiVersion: operators.coreos.com/v1alpha1
kind: ClusterServiceVersion
metadata:
name: my-operator-v1.2.3
annotations:
operators.operatorframework.io/internal-objects: '["my.internal.crd1.io","my.internal.crd2.io"]' (1)
...
1 Set any internal CRDs as an array of strings.
Initializing required custom resources
An Operator might require the user to instantiate a custom resource before the Operator can be fully functional. However, it can be challenging for a user to determine what is required or how to define the resource.
As an Operator developer, you can specify a single required custom resource that must be created at the time that the Operator is installed by adding the operatorframework.io/initialization-resource
annotation to the cluster service version (CSV). The annotation must include a template that contains a complete YAML definition that is required to initialize the resource during installation.
If this annotation is defined, after installing the Operator from the OKD web console, the user is prompted to create the resource using the template provided in the CSV.
Procedure
Add the
operatorframework.io/initialization-resource
annotation to the CSV of your Operator to specify a required custom resource. For example, the following annotation requires the creation of aStorageCluster
resource and provides a full YAML definition:Initialization resource annotation
apiVersion: operators.coreos.com/v1alpha1
kind: ClusterServiceVersion
metadata:
name: my-operator-v1.2.3
annotations:
operatorframework.io/initialization-resource: |-
{
"apiVersion": "ocs.openshift.io/v1",
"kind": "StorageCluster",
"metadata": {
"name": "example-storagecluster"
},
"spec": {
"manageNodes": false,
"monPVCTemplate": {
"spec": {
"accessModes": [
"ReadWriteOnce"
],
"resources": {
"requests": {
"storage": "10Gi"
}
},
"storageClassName": "gp2"
}
},
"storageDeviceSets": [
{
"count": 3,
"dataPVCTemplate": {
"spec": {
"accessModes": [
"ReadWriteOnce"
],
"resources": {
"requests": {
"storage": "1Ti"
}
},
"storageClassName": "gp2",
"volumeMode": "Block"
}
},
"name": "example-deviceset",
"placement": {},
"portable": true,
"resources": {}
}
]
}
}
...
Understanding your API services
As with CRDs, there are two types of API services that your Operator may use: owned and required.
Owned API services
When a CSV owns an API service, it is responsible for describing the deployment of the extension api-server
that backs it and the group/version/kind (GVK) it provides.
An API service is uniquely identified by the group/version it provides and can be listed multiple times to denote the different kinds it is expected to provide.
Field | Description | Required/optional |
---|---|---|
| Group that the API service provides, for example | Required |
| Version of the API service, for example | Required |
| A kind that the API service is expected to provide. | Required |
| The plural name for the API service provided. | Required |
| Name of the deployment defined by your CSV that corresponds to your API service (required for owned API services). During the CSV pending phase, the OLM Operator searches the | Required |
| A human readable version of your API service name, for example | Required |
| A short description of how this API service is used by the Operator or a description of the functionality provided by the API service. | Required |
| Your API services own one or more types of Kubernetes objects. These are listed in the resources section to inform your users of the objects they might need to troubleshoot or how to connect to the application, such as the service or ingress rule that exposes a database. It is recommended to only list out the objects that are important to a human, not an exhaustive list of everything you orchestrate. For example, do not list config maps that store internal state that are not meant to be modified by a user. | Optional |
| Essentially the same as for owned CRDs. | Optional |
API service resource creation
Operator Lifecycle Manager (OLM) is responsible for creating or replacing the service and API service resources for each unique owned API service:
Service pod selectors are copied from the CSV deployment matching the
DeploymentName
field of the API service description.A new CA key/certificate pair is generated for each installation and the base64-encoded CA bundle is embedded in the respective API service resource.
API service serving certificates
OLM handles generating a serving key/certificate pair whenever an owned API service is being installed. The serving certificate has a common name (CN) containing the hostname of the generated Service
resource and is signed by the private key of the CA bundle embedded in the corresponding API service resource.
The certificate is stored as a type kubernetes.io/tls
secret in the deployment namespace, and a volume named apiservice-cert
is automatically appended to the volumes section of the deployment in the CSV matching the DeploymentName
field of the API service description.
If one does not already exist, a volume mount with a matching name is also appended to all containers of that deployment. This allows users to define a volume mount with the expected name to accommodate any custom path requirements. The path of the generated volume mount defaults to /apiserver.local.config/certificates
and any existing volume mounts with the same path are replaced.
Required API services
OLM ensures all required CSVs have an API service that is available and all expected GVKs are discoverable before attempting installation. This allows a CSV to rely on specific kinds provided by API services it does not own.
Field | Description | Required/optional |
---|---|---|
| Group that the API service provides, for example | Required |
| Version of the API service, for example | Required |
| A kind that the API service is expected to provide. | Required |
| A human readable version of your API service name, for example | Required |
| A short description of how this API service is used by the Operator or a description of the functionality provided by the API service. | Required |