# CHANGELOG

## 0.20.0

**Note: This is the last version of Strimzi that will support Kubernetes 1.11 and higher. Future versions will drop support for Kubernetes 1.11-1.15 and support only Kubernetes 1.16 and higher.**

* Add support for Kafka 2.5.1 and 2.6.0. Remove support for 2.4.0 and 2.4.1
* Remove TLS sidecars from Kafka pods => Kafka now uses native TLS to connect to ZooKeeper
* Updated to Cruise Control 2.5.11, which adds Kafka 2.6.0 support and fixes a previous issue with CPU utilization statistics for containers. As a result, the CpuCapacityGoal has now been enabled.
* Cruise Control metrics integration:
  * Enable metrics JMX exporter configuration in the `cruiseControl` property of the Kafka custom resource
  * New Grafana dashboard for the Cruise Control metrics
* Configure Cluster Operator logging using ConfigMap instead of environment variable and support dynamic changes  
* Switch to use the `AclAuthorizer` class for the `simple` Kafka authorization type. `AclAuthorizer` contains new features such as the ability to control the amount of authorization logs in the broker logs.
* Support dynamically changeable logging configuration of Kafka Connect and Kafka Connect S2I
* Support dynamically changeable logging configuration of Kafka brokers
* Support dynamically changeable logging configuration of Kafka MirrorMaker2
* Add support for `client.rack` property for Kafka Connect to use `fetch from closest replica` feature. 
* Refactored operators Grafana dashboard
  * Fixed bug on maximum reconcile time graph
  * Removed the avarage reconcile time graph
  * Rearranged graphs
* Make `listeners` configurable as an array and add support for more different listeners in single cluster
* Add support for configuring `hostAliases` in Pod templates
* Add new resource state metric in the operators for reflecting the reconcile result on a specific resource
* Add improvements for `oauth` authentication, and `keycloak` authorization:
  * Support for re-authentication was added, which also enforces access token lifespan on the Kafka client session
  * Permission changes through Keycloak Authorization Services are now detected by Kafka Brokers

### Deprecations and removals

#### Redesign of the `.spec.kafka.listeners` section

The `.spec.kafka.listeners` section of the Kafka CRD has been redesigned to allow configuring more different listeners.
The old `listeners` object which allowed only configuration of one`plain`, one `tls`, and one `external` listener is now deprecated and will be removed in the future.
It is replaced with an array allowing configuration of multiple different listeners:

```yaml
listeners:
  - name: local
    port: 9092
    type: internal
    tls: true
  - name: external1
    port: 9093
    type: loadbalancer
    tls: true
  - name: external2
    port: 9094
    type: nodeport
    tls: true
```

This change includes some other changes:
* The `tls` field is now required.
* The former `overrides` section is now merged with the `configuration` section.
* The `dnsAnnotations` field has been renamed to `annotations` since we found out it has wider use.
* Configuration of `loadBalancerSourceRanges` and `externalTrafficPolicy` has been moved into listener configuration. Its use in the `template` section is now deprecated.
* For `type: internal` listeners, you can now use the flag `useServiceDnsDomain` to define whether they should use the fully qualified DNS names including the cluster service suffix (usually `.cluster.local`). This option defaults to false.
* All listeners now support configuring the advertised hostname and port.
* `preferredAddressType` has been removed to `preferredNodePortAddressType`.

To convert the old format into the new format with backwards compatibility, you should use following names and types:
* For the old `plain` listener, use the name `plain`, port `9092` and type `internal`.
* For the old `tls` listener, use the name `tls`, port `9093` and type `internal`.
* For the old `external` listener, use the name `external`, port `9094`.

For example the following old configuration:

```yaml
listeners:
  plain:
    # ...
  tls: 
    # ...
  external:
    type: loadbalancer 
    # ...
```

Will look like this in the new format:

```yaml
listeners:
  - name: plain
    port: 9092
    type: internal
    tls: false
  - name: tls
    port: 9093
    type: internal
    tls: true
  - name: external
    port: 9094
    type: loadbalancer
    tls: true
```

#### Removal of monitoring port on Kafka and ZooKeeper related services

The `PodMonitor` resource is now used instead of the `ServiceMonitor` for scraping metrics from Kafka, ZooKeeper, Kafka Connect and so on.
For this reason, we have removed the monitoring port `tcp-prometheus` (9404) on all the services where it is declared (Kafka bootstrap, ZooKeeper client and so on).
It was already deprecated in the previous 0.19.0 release.
Together with it we have also removed the Prometheus annotations from the services. If you want to add them, you can use the templates.
See here https://strimzi.io/docs/operators/master/using.html#assembly-customizing-kubernetes-resources-str for more details about templates usage.
Finally, the Kafka Exporter service was has been removed because it was used just for the monitoring port.

#### Deprecation of Kafka TLS sidecar configuration

Since the Kafka TLS sidecar has been removed, the related configuration options in the Kafka custom resource are now deprecated:
* `.spec.kafka.tlsSidecar`
* `.spec.kafka.template.tlsSidecar`

## 0.19.0

* Add support for authorization using Open Policy Agent
* Add support for scale subresource to make scaling of following resources easier:
  * KafkaConnect
  * KafkaConnectS2I
  * KafkaBridge
  * KafkaMirrorMaker
  * KafkaMirrorMaker2
  * KafkaConnector 
* Remove deprecated `Kafka.spec.topicOperator` classes and deployment logic
* Use Java 11 as the Java runtime
* Removed the need to manually create Cruise Control metrics topics if topic auto creation is disabled.
* Migration to Helm 3
* Refactored the format of the `KafkaRebalance` resource's status. The state of the rebalance is now displayed in the associated `Condition`'s `type` field rather than the `status` field. This was done so that the information would display correctly in various Kubernetes tools.
* Added performance tuning options to the `KafkaRebalance` CR and the ability to define a regular expression that will exclude matching topics from a rebalance optimization proposal.
* Use Strimzi Kafka Bridge 0.18.0
* Make it possible to configure labels and annotations for secrets created by the User Operator
* Strimzi Kafka Bridge metrics integration:
  * enable/disable metrics in the KafkaBridge custom resource
  * new Grafana dashboard for the bridge metrics
* Support dynamically changeable logging in the Entity Operator and Kafka Bridge 
* Extended the Grafana example dashboard for Kafka Connect to provide more relevant information

### Deprecations and removals

#### Deprecation of Helm v2 chart

The Helm v2 support will end soon. 
Bug fixing should stop on August 13th 2020 and security fixes on November 13th.
See https://helm.sh/blog/covid-19-extending-helm-v2-bug-fixes/ for more details.

In sync with that, the Helm v2 chart of Strimzi Cluster Operator is now deprecated and will be removed in the future as Helm v2 support ends.
Since Strimzi 0.19.0, we have a new chart for Helm v3 which can be used instead.

#### Removal of v1alpha1 versions of several custom resources

In Strimzi 0.12.0, the `v1alpha1` versions of the following resources have been deprecated and replaced by `v1beta1`:
* `Kafka`
* `KafkaConnect`
* `KafkaConnectS2I`
* `KafkaMirrorMaker`
* `KafkaTopic`
* `KafkaUser`

In the next release, the `v1alpha1` versions of these resources will be removed. 
Please follow the guide for upgrading the resources: https://strimzi.io/docs/operators/latest/full/deploying.html#assembly-upgrade-resources-str.

#### Removal deprecated cadvisor metric labels

The `pod_name` and `container_name` labels provided on the cadvisor metrics are now just `pod` and `container` starting from Kubernetes 1.16.
We removed the old ones from the Prometheus scraping configuration/alerts and on the Kafka and ZooKeeper dashboard as well.
It means that the charts related to memory and CPU usage are not going to work on Kuvbernetes version previous 1.14.
For more information on what is changed: https://github.com/strimzi/strimzi-kafka-operator/pull/3312

#### Deprecation of monitoring port on Kafka and ZooKeeper related services

The `PodMonitor` resource is now used instead of the `ServiceMonitor` for scraping metrics from Kafka, ZooKeeper, Kafka Connect and so on.
For this reason, we are deprecating the monitoring port `tcp-prometheus` (9404) on all the services where it is declared (Kafka bootstrap, ZooKeeper client and so on).
This port will be removed in the next release.
Together with it we will also remove the Prometheus annotation from the service.

#### Removal warning of Cluster Operator log level

Because of the new Cluster Operator dynamic logging configuration via [PR#3328](https://github.com/strimzi/strimzi-kafka-operator/pull/3328) we are going to remove the `STRIMZI_LOG_LEVEL` environment variable from the Cluster Operator deployment YAML file in the 0.20.0 release.

## 0.18.0

* Add possibility to set Java System Properties for User Operator and Topic Operator via `Kafka` CR.
* Make it possible to configure PodManagementPolicy for StatefulSets
* Update build system to use `yq` version 3 (https://github.com/mikefarah/yq)
* Add more metrics to Cluster and User Operators
* New Grafana dashboard for Operator monitoring 
* Allow `ssl.cipher.suites`, `ssl.protocol` and `ssl.enabled.protocols` to be configurable for Kafka and the different components supported by Strimzi
* Add support for user configurable SecurityContext for each Strimzi container
* Allow standalone User Operator to modify status on KafkaUser
* Add support for Kafka 2.4.1
* Add support for Kafka 2.5.0
* Remove TLS sidecars from ZooKeeper pods, using native ZooKeeper TLS support instead
* Add metrics for Topic Operator
* Use Strimzi Kafka Bridge 0.16.0
* Add support for CORS in the HTTP Kafka Bridge
* Pass HTTP Proxy configuration from operator to operands
* Add Cruise Control support, KafkaRebalance resource and rebalance operator

## 0.17.0

* Add possibility to set Java System Properties via CR yaml
* Add support for Mirror Maker 2.0
* Add Jmxtrans deployment
* Add public keys of TLS listeners to the status section of the Kafka CR
* Add support for using a Kafka authorizer backed by Keycloak Authorization Services

## 0.16.0

* Add support for Kafka 2.4.0 and upgrade from Zookeeper 3.4.x to 3.5.x
* Drop support for Kafka 2.2.1 and 2.3.0
* Add KafkaConnector resource and connector operator
* Let user choose which node address will be used as advertised host (`ExternalDNS`, `ExternalIP`, `InternalDNS`, `InternalIP` or `Hostname`)
* Add support for tini
* When not explicitly configured by the user in `jvmOptions`, `-Xmx` option is calculated from memory requests rather than from memory limits
* Expose JMX port on Kafka brokers via an internal service
* Add support for `externalTrafficPolicy` and `loadBalancerSourceRanges` properties on loadbalancer and nodeport type services
* Add support for user quotas
* Add support for Istio protocol selection in service port names  
Note: Strimzi is essentially adding a `tcp-` prefix to the port names in Kafka services and headless services.  
(e.g clientstls -> tcp-clientstls)
* Add service discovery labels and annotations
* Add possibility to specify custom server certificates to TLS based listeners

## 0.15.0

* Drop support for Kafka 2.1.0, 2.1.1, and 2.2.0
* Add support for Kafka 2.3.1
* Improved Kafka rolling update
* Improve Kafka Exporter Grafana dashboard
* Add sizeLimit option to ephemeral storage (#1505)
* Add `schedulerName` to `podTemplate` (#2114)
* Allow overriding the auto-detected Kubernetes version
* Garbage Collection (GC) logging disabled by default
* Providing PKCS12 truststore and password in the cluster and clients CA certificates Secrets
* Providing PKCS12 keystore and password in the TLS based KafkaUser related Secret

## 0.14.0

* Add support for configuring Ingress class (#1716)
* Add support for setting custom environment variables in all containers
* Add liveness and readiness checks to Mirror Maker
* Allow configuring loadBalancerIP for LoadBalancer type services
* Allow setting labels and annotations for Persistent Volume Claims
* Add support for Jaeger tracing in Kafka Mirror Maker and Kafka Connect
* Add support for deploying Kafka Exporter
* Add initial support for OAuth authentication

## 0.13.0

* Allow users to manually configure ACL rules (for example, using `kafka-acls.sh`) for special Kafka users `*` and `ANONYMOUS` without them being deleted by the User Operator
* Add support for configuring a Priority Class name for Pods deployed by Strimzi
* Add support for Kafka 2.3.0
* Add support for Kafka User resource status
* Add support for Kafka Connect resource status
* Add support for Kafka Connect S2I resource status
* Add support for Kafka Bridge resource status
* Add support for Kafka Mirror Maker resource status
* Add support for DNS annotations to `nodeport` type external listeners

## 0.12.0

* **Drop support for Kubernetes 1.9 and 1.10 and OpenShift 3.9 and 3.10.**
**Versions supported since Strimzi 0.12.0 are Kubernetes 1.11 and higher and OpenShift 3.11 and higher.** 
**This was required because the CRD versioning and CRD subresources support.** 
* Added support for Kafka 2.2.0 and 2.1.1, dropped support for Kafka 2.0.0 and 2.0.1
* Persistent storage improvements
  * Add resizing of persistent volumes
  * Allow to specify different storage class for every broker
  * Adding and removing volumes in Jbod Storage
* Custom Resources improvements
  * New CRD version `v1beta1`. See documentation for more information about upgrading from `v1alpha1` to `v1beta1`.
  * Log at the warn level when a custom resource uses deprecated or unknown properties
  * Add initial support for the `status` sub-resource in the `Kafka` custom resource 
* Add support for [Strimzi Kafka Bridge](https://github.com/strimzi/strimzi-kafka-bridge) for HTTP protocol
* Reduce the number of container images needed to run Strimzi to just two: `kafka` and `operator`.
* Add support for unprivileged users to install the operator with Helm
* Support experimental off-cluster access using Kubernetes Nginx Ingress
* Add ability to configure Image Pull Secrets for all pods in Cluster Operator
* Support for SASL PLAIN mechanism in Kafka Connect and Mirror Maker (for use with non-Strimzi Kafka cluster)

## 0.11.0

* Add support for JBOD storage for Kafka brokers
* Allow users to configure the default ImagePullPolicy
* Add Prometheus alerting
    * Resources for alert manager deployment and configuration
    * Alerting rules with alert examples from Kafka and Zookeeper metrics
* Enrich configuration options for off cluster access
* Support for watching all namespaces
* Operator Lifecycle Manager integration

## 0.10.0

* Support for Kafka 2.1.0
* Support for Kafka upgrades
* Add healthchecks to TLS sidecars
* Add support for new fields in the Pod template: terminationGracePeriod, securityContext and imagePullSecrets
* Rename annotations to use the `strimzi.io` domain consistently (The old annotations are deprecated, but still functional):
    * `cluster.operator.strimzi.io/delete-claim` → `strimzi.io/delete-claim` 
    * `operator.strimzi.io/manual-rolling-update` → `strimzi.io/manual-rolling-update` 
    * `operator.strimzi.io/delete-pod-and-pvc` → `strimzi.io/delete-pod-and-pvc`
    * `operator.strimzi.io/generation` → `strimzi.io/generation`
* Add support for mounting Secrets and Config Maps into Kafka Connect and Kafka Connect S2I
* Add support for NetworkPolicy peers in listener configurations
* Make sure the TLS sidecar pods shutdown only after the main container
* Add support for Pod Disruption Budgets

## 0.9.0

* Add possibility to label and annotate different resources (#1039)
* Add support for TransactionalID in KafkaUser resource
* Update to Kafka 2.0.1
* Add maintenance time windows support for allowing CA certificates renewal rolling update started only in specific times (#1117)  
* Add support for upgrading between Kafka versions (#1103). This removes support for `STRIMZI_DEFAULT_KAFKA_IMAGE` environment variable in the Cluster Operator, replacing it with `STRIMZI_KAFKA_IMAGES`.  


## 0.8.2

* Run images under group 0 to avoid storage issues

## 0.8.1

* Fix certificate renewal issues

## 0.8.0

* Support for unencrypted connections on LoadBalancers and NodePorts.
* Better support for TLS hostname verification for external connections
* Certificate renewal / expiration
* Mirror Maker operator
* Triggering rolling update / pod deletion manually

## 0.7.0

* Exposing Kafka to the outside using:
  * OpenShift Routes
  * LoadBalancers
  * NodePorts
* Use less wide RBAC permissions (`ClusterRoleBindings` where converted to `RoleBindings` where possible)
* Support for SASL authentication using the SCRAM-SHA-512 mechanism added to Kafka Connect and Kafka Connect with S2I support 
* Network policies for managing access to Zookeeper ports and Kafka replication ports
* Use OwnerReference and Kubernetes garbage collection feature to delete resources and to track the ownership

## 0.6.0

* Helm chart for Strimzi Cluster Operator
* Topic Operator moving to Custom Resources instead of Config Maps
* Make it possible to enabled and disable:
  * Listeners
  * Authorization
  * Authentication
* Configure Kafka _super users_ (`super.users` field in Kafka configuration)
* User Operator
  * Managing users and their ACL rights
* Added new Entity Operator for deploying:
  * User Operator
  * Topic Operator
* Deploying the Topic Operator outside of the new Entity Operator is now deprecated
* Kafka 2.0.0
* Kafka Connect:
  * Added TLS support for connecting to the Kafka cluster
  * Added TLS client authentication when connecting to the Kafka cluster 

## 0.5.0

* The Cluster Operator now manages RBAC resource for managed resources:
    * `ServiceAccount` and `ClusterRoleBindings` for Kafka pods
    * `ServiceAccount` and `RoleBindings` for the Topic Operator pods
* Renaming of Kubernetes services (Backwards incompatible!)
  * Kubernetes services for Kafka, Kafka Connect and Zookeeper have been renamed to better correspond to their purpose
  * `xxx-kafka` -> `xxx-kafka-bootstrap`
  * `xxx-kafka-headless` -> `xxx-kafka-brokers`
  * `xxx-zookeeper` -> `xxx-zookeeper-client`
  * `xxx-zookeeper-headless` -> `xxx-zookeeper-nodes`
  * `xxx-connect` -> `xxx-connect-api`
* Cluster Operator moving to Custom Resources instead of Config Maps
* TLS support has been added to Kafka, Zookeeper and Topic Operator. The following channels are now encrypted:
    * Zookeeper cluster communication
    * Kafka cluster commbunication
    * Communication between Kafka and Zookeeper
    * Communication between Topic Operator and Kafka / Zookeeper
* Logging configuration for Kafka, Kafka Connect and Zookeeper
* Add support for [Pod Affinity and Anti-Affinity](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#affinity-and-anti-affinity)
* Add support for [Tolerations](https://v1-9.docs.kubernetes.io/docs/reference/generated/kubernetes-api/v1.9/#toleration-v1-core)
* Configuring different JVM options
* Support for broker rack in Kafka

## 0.4.0

* Better configurability of Kafka, Kafka Connect, Zookeeper
* Support for Kubernetes request and limits
* Support for JVM memory configuration of all components
* Controllers renamed to operators
* Improved log verbosity of Cluster Operator
* Update to Kafka 1.1.0
