<h1>Cluster manifest reference</h1>

Individual Postgres clusters are described by the Kubernetes *cluster manifest*
that has the structure defined by the `postgresql` CRD (custom resource
definition). The following section describes the structure of the manifest and
the purpose of individual keys. You can take a look at the examples of the
[minimal](../../manifests/minimal-postgres-manifest.yaml)
and the
[complete](../../manifests/complete-postgres-manifest.yaml)
cluster manifests.

When Kubernetes resources, such as memory, CPU or volumes, are configured,
their amount is usually described as a string together with the units of
measurements. Please, refer to the [Kubernetes
documentation](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/)
for the possible values of those.

:exclamation: If both operator configmap/CRD and a Postgres cluster manifest
define the same parameter, the value from the Postgres cluster manifest is
applied.

## Manifest structure

A Postgres manifest is a `YAML` document. On the top level both individual
parameters and parameter groups can be defined. Parameter names are written
in camelCase.

## Cluster metadata

Those parameters are grouped under the `metadata` top-level key.

* **name**
  the name of the cluster. Must start with the `teamId` followed by a dash.
  Changing it after the cluster creation is not supported. Required field.

* **namespace**
  the namespace where the operator creates Kubernetes objects (i.e. pods,
  services, secrets) for the cluster. Changing it after the cluster creation
  results in deploying or updating a completely separate cluster in the target
  namespace. Optional (if present, should match the namespace where the
  manifest is applied).

* **labels**
  if labels are matching one of the `inherited_labels` [configured in the
  operator parameters](operator_parameters.md#kubernetes-resources),
  they will automatically be added to all the objects (StatefulSet, Service,
  Endpoints, etc.) that are created by the operator.
  Labels that are set here but not listed as `inherited_labels` in the operator
  parameters are ignored.

## Top-level parameters

These parameters are grouped directly under  the `spec` key in the manifest.

* **teamId**
  name of the team the cluster belongs to. Changing it after the cluster
  creation is not supported. Required field.

* **numberOfInstances**
  total number of  instances for a given cluster. The operator parameters
  `max_instances` and `min_instances` may also adjust this number. Required
  field.

* **dockerImage**
  custom Docker image that overrides the **docker_image** operator parameter.
  It should be a [Spilo](https://github.com/zalando/spilo) image. Optional.

* **spiloRunAsUser**
  sets the user ID which should be used in the container to run the process.
  This must be set to run the container without root. By default the container
  runs with root. This option only works for Spilo versions >= 1.6-p3.

* **spiloRunAsGroup**
  sets the group ID which should be used in the container to run the process.
  This must be set to run the container without root. By default the container
  runs with root. This option only works for Spilo versions >= 1.6-p3.

* **spiloFSGroup**
  the Persistent Volumes for the Spilo pods in the StatefulSet will be owned and
  writable by the group ID specified. This will override the **spilo_fsgroup**
  operator parameter. This is required to run Spilo as a non-root process, but
  requires a custom Spilo image. Note the FSGroup of a Pod cannot be changed
  without recreating a new Pod. Optional.

* **enableMasterLoadBalancer**
  boolean flag to override the operator defaults (set by the
  `enable_master_load_balancer` parameter) to define whether to enable the load
  balancer pointing to the Postgres primary. Optional.

* **enableReplicaLoadBalancer**
  boolean flag to override the operator defaults (set by the
  `enable_replica_load_balancer` parameter) to define whether to enable the
  load balancer pointing to the Postgres standby instances. Optional.

* **allowedSourceRanges**
  when one or more load balancers are enabled for the cluster, this parameter
  defines the comma-separated range of IP networks (in CIDR-notation). The
  corresponding load balancer is accessible only to the networks defined by
  this parameter. Optional, when empty the load balancer service becomes
  inaccessible from outside of the Kubernetes cluster.

* **users**
  a map of usernames to user flags for the users that should be created in the
  cluster by the operator. User flags are a list, allowed elements are
  `SUPERUSER`, `REPLICATION`, `INHERIT`, `LOGIN`, `NOLOGIN`, `CREATEROLE`,
  `CREATEDB`, `BYPASSURL`. A login user is created by default unless NOLOGIN is
  specified, in which case the operator creates a role. One can specify empty
  flags by providing a JSON empty array '*[]*'. Optional.

* **databases**
  a map of database names to database owners for the databases that should be
  created by the operator. The owner users should already exist on the cluster
  (i.e. mentioned in the `user` parameter). Optional.

* **tolerations**
  a list of tolerations that apply to the cluster pods. Each element of that
  list is a dictionary with the following fields: `key`, `operator`, `value`,
  `effect` and `tolerationSeconds`. Each field is optional. See [Kubernetes
  examples](https://kubernetes.io/docs/concepts/configuration/taint-and-toleration/)
  for details on tolerations and possible values of those keys. When set, this
  value overrides the `pod_toleration` setting from the operator. Optional.

* **podPriorityClassName**
  a name of the [priority
  class](https://kubernetes.io/docs/concepts/configuration/pod-priority-preemption/#priorityclass)
  that should be assigned to the cluster pods. When not specified, the value
  is taken from the `pod_priority_class_name` operator parameter, if not set
  then the default priority class is taken. The priority class itself must be
  defined in advance. Optional.

* **podAnnotations**
  A map of key value pairs that gets attached as [annotations](https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/)
  to each pod created for the database.

* **serviceAnnotations**
  A map of key value pairs that gets attached as [annotations](https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/)
  to the services created for the database cluster. Check the
  [administrator docs](https://github.com/zalando/postgres-operator/blob/master/docs/administrator.md#load-balancers-and-allowed-ip-ranges)
  for more information regarding default values and overwrite rules.

* **enableShmVolume**
  Start a database pod without limitations on shm memory. By default Docker
  limit `/dev/shm` to `64M` (see e.g. the [docker
  issue](https://github.com/docker-library/postgres/issues/416), which could be
  not enough if PostgreSQL uses parallel workers heavily. If this option is
  present and value is `true`, to the target database pod will be mounted a new
  tmpfs volume to remove this limitation. If it's not present, the decision
  about mounting a volume will be made based on operator configuration
  (`enable_shm_volume`, which is `true` by default). It it's present and value
  is `false`, then no volume will be mounted no matter how operator was
  configured (so you can override the operator configuration). Optional.

* **enableConnectionPooler**
  Tells the operator to create a connection pooler with a database for the master
  service. If this field is true, a connection pooler deployment will be created even if
  `connectionPooler` section is empty. Optional, not set by default.

* **enableReplicaConnectionPooler**
  Tells the operator to create a connection pooler with a database for the replica
  service. If this field is true, a connection pooler deployment for replica
  will be created even if `connectionPooler` section is empty. Optional, not set by default.

* **enableLogicalBackup**
  Determines if the logical backup of this cluster should be taken and uploaded
  to S3. Default: false. Optional.

* **logicalBackupSchedule**
  Schedule for the logical backup K8s cron job. Please take
  [the reference schedule format](https://kubernetes.io/docs/tasks/job/automated-tasks-with-cron-jobs/#schedule)
  into account. Optional. Default is: "30 00 \* \* \*"

* **additionalVolumes**
  List of additional volumes to mount in each container of the statefulset pod.
  Each item must contain a `name`, `mountPath`, and `volumeSource` which is a
  [kubernetes volumeSource](https://godoc.org/k8s.io/api/core/v1#VolumeSource).
  It allows you to mount existing PersistentVolumeClaims, ConfigMaps and Secrets inside the StatefulSet.
  Also an `emptyDir` volume can be shared between initContainer and statefulSet.
  Additionaly, you can provide a `SubPath` for volume mount (a file in a configMap source volume, for example).
  You can also specify in which container the additional Volumes will be mounted with the `targetContainers` array option.
  If `targetContainers` is empty, additional volumes will be mounted only in the `postgres` container.
  If you set the `all` special item, it will be mounted in all containers (postgres + sidecars).
  Else you can set the list of target containers in which the additional volumes will be mounted (eg : postgres, telegraf)

## Postgres parameters

Those parameters are grouped under the `postgresql` top-level key, which is
required in the manifest.

* **version**
  the Postgres major version of the cluster. Looks at the [Spilo
  project](https://github.com/zalando/spilo/releases) for the list of supported
  versions. Changing the cluster version once the cluster has been bootstrapped
  is not supported. Required field.

* **parameters**
  a dictionary of Postgres parameter names and values to apply to the resulting
  cluster. Optional (Spilo automatically sets reasonable defaults for parameters
  like `work_mem` or `max_connections`).

## Patroni parameters

Those parameters are grouped under the `patroni` top-level key. See the [Patroni
documentation](https://patroni.readthedocs.io/en/latest/SETTINGS.html) for the
explanation of `ttl` and `loop_wait` parameters.

* **initdb**
  a map of key-value pairs describing initdb parameters. For `data-checksum`,
  `debug`, `no-locale`, `noclean`, `nosync` and `sync-only` parameters use
  `true` as the value if you want to set them. Changes to this option do not
  affect the already initialized clusters. Optional.

* **pg_hba**
  list of custom `pg_hba` lines to replace default ones. Note that the default
  ones include

  ```
  hostssl all +pamrole all pam
  ```
  where pamrole is the name of the role for the pam authentication; any
  custom `pg_hba` should include the pam line to avoid breaking pam
  authentication. Optional.

* **ttl**
  Patroni `ttl` parameter value, optional. The default is set by the Spilo
  Docker image. Optional.

* **loop_wait**
  Patroni `loop_wait` parameter value, optional. The default is set by the
  Spilo Docker image. Optional.

* **retry_timeout**
  Patroni `retry_timeout` parameter value, optional. The default is set by the
  Spilo Docker image. Optional.

* **maximum_lag_on_failover**
  Patroni `maximum_lag_on_failover` parameter value, optional. The default is
  set by the Spilo Docker image. Optional.

* **slots**
  permanent replication slots that Patroni preserves after failover by
  re-creating them on the new primary immediately after doing a promote. Slots
  could be reconfigured with the help of `patronictl edit-config`. It is the
  responsibility of a user to avoid clashes in names between replication slots
  automatically created by Patroni for cluster members and permanent replication
  slots. Optional.

* **synchronous_mode**
  Patroni `synchronous_mode` parameter value. The default is set to `false`. Optional.

* **synchronous_mode_strict**
  Patroni `synchronous_mode_strict` parameter value. Can be used in addition to `synchronous_mode`. The default is set to `false`. Optional.

## Postgres container resources

Those parameters define [CPU and memory requests and limits](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container/)
for the Postgres container. They are grouped under the `resources` top-level
key with subgroups `requests` and `limits`.

### Requests

CPU and memory requests for the Postgres container.

* **cpu**
  CPU requests for the Postgres container. Optional, overrides the
  `default_cpu_requests` operator configuration parameter. Optional.

* **memory**
  memory requests for the Postgres container. Optional, overrides the
  `default_memory_request` operator configuration parameter. Optional.

### Limits

CPU and memory limits for the Postgres container.

* **cpu**
  CPU limits for the Postgres container. Optional, overrides the
  `default_cpu_limits` operator configuration parameter. Optional.

* **memory**
  memory limits for the Postgres container. Optional, overrides the
  `default_memory_limits` operator configuration parameter. Optional.

## Parameters defining how to clone the cluster from another one

Those parameters are applied when the cluster should be a clone of another one
that is either already running or has a basebackup on S3. They are grouped
under the `clone` top-level key and do not affect the already running cluster.

* **cluster**
  name of the cluster to clone from. Translated to either the service name or
  the key inside the S3 bucket containing base backups. Required when the
  `clone` section is present.

* **uid**
  Kubernetes UID of the cluster to clone from. Since cluster name is not a
  unique identifier of the cluster (as identically named clusters may exist in
  different namespaces) , the operator uses UID in the S3 bucket name in order
  to guarantee uniqueness. Has no effect when cloning from the running
  clusters. Optional.

* **timestamp**
  the timestamp up to which the recovery should proceed. The operator always
  configures non-inclusive recovery target, stopping right before the given
  timestamp. When this parameter is set the operator will not consider cloning
  from the live cluster, even if it is running, and instead goes to S3. Optional.

* **s3_wal_path**
  the url to S3 bucket containing the WAL archive of the cluster to be cloned.
  Optional.

* **s3_endpoint**
  the url of the S3-compatible service should be set when cloning from non AWS
  S3. Optional.

* **s3_access_key_id**
  the access key id, used for authentication on S3 service. Optional.

* **s3_secret_access_key**
  the secret access key, used for authentication on S3 service. Optional.

* **s3_force_path_style**
  to enable path-style addressing(i.e., http://s3.amazonaws.com/BUCKET/KEY)
  when connecting to an S3-compatible service that lack of support for
  sub-domain style bucket URLs (i.e., http://BUCKET.s3.amazonaws.com/KEY).
  Optional.

## Standby cluster

On startup, an existing `standby` top-level key creates a standby Postgres
cluster streaming from a remote location. So far only streaming from a S3 WAL
archive is supported.

* **s3_wal_path**
  the url to S3 bucket containing the WAL archive of the remote primary.
  Required when the `standby` section is present.

## EBS volume resizing

Those parameters are grouped under the `volume` top-level key and define the
properties of the persistent storage that stores Postgres data.

* **size**
  the size of the target EBS volume. Usual Kubernetes size modifiers, i.e. `Gi`
  or `Mi`, apply. Required.

* **storageClass**
  the name of the Kubernetes storage class to draw the persistent volume from.
  See [Kubernetes
  documentation](https://kubernetes.io/docs/concepts/storage/storage-classes/)
  for the details on storage classes. Optional.

* **subPath**
  Subpath to use when mounting volume into Spilo container. Optional.

## Sidecar definitions

Those parameters are defined under the `sidecars` key. They consist of a list
of dictionaries, each defining one sidecar (an extra container running
along the main Postgres container on the same pod). The following keys can be
defined in the sidecar dictionary:

* **name**
  name of the sidecar. Required.

* **image**
  Docker image of the sidecar. Required.

* **env**
  a dictionary of environment variables. Use usual Kubernetes definition
  (https://kubernetes.io/docs/tasks/inject-data-application/environment-variable-expose-pod-information/)
  for environment variables. Optional.

* **resources**
  [CPU and memory requests and limits](https://kubernetes.io/docs/concepts/configuration/manage-compute-resources-container)
  for each sidecar container. Optional.

### Requests

CPU and memory requests for the sidecar container.

* **cpu**
  CPU requests for the sidecar container. Optional, overrides the
  `default_cpu_requests` operator configuration parameter. Optional.

* **memory**
  memory requests for the sidecar container. Optional, overrides the
  `default_memory_request` operator configuration parameter. Optional.

### Limits

CPU and memory limits for the sidecar container.

* **cpu**
  CPU limits for the sidecar container. Optional, overrides the
  `default_cpu_limits` operator configuration parameter. Optional.

* **memory**
  memory limits for the sidecar container. Optional, overrides the
  `default_memory_limits` operator configuration parameter. Optional.

## Connection pooler

Parameters are grouped under the `connectionPooler` top-level key and specify
configuration for connection pooler. If this section is not empty, a connection
pooler will be created for master service only even if `enableConnectionPooler`
is not present. But if this section is present then it defines the configuration
for both master and replica pooler services (if `enableReplicaConnectionPooler`
 is enabled).

* **numberOfInstances**
  How many instances of connection pooler to create.

* **schema**
  Database schema to create for credentials lookup function.

* **user**
  User to create for connection pooler to be able to connect to a database.
  You can also choose a role from the `users` section or a system user role.

* **dockerImage**
  Which docker image to use for connection pooler deployment.

* **maxDBConnections**
  How many connections the pooler can max hold. This value is divided among the
  pooler pods.

* **mode**
  In which mode to run connection pooler, transaction or session.

* **resources**
  Resource configuration for connection pooler deployment.

## Custom TLS certificates

Those parameters are grouped under the `tls` top-level key.

* **secretName**
  By setting the `secretName` value, the cluster will switch to load the given
  Kubernetes Secret into the container as a volume and uses that as the
  certificate instead. It is up to the user to create and manage the
  Kubernetes Secret either by hand or using a tool like the CertManager
  operator.

* **certificateFile**
  Filename of the certificate. Defaults to "tls.crt".

* **privateKeyFile**
  Filename of the private key. Defaults to "tls.key".

* **caFile**
  Optional filename to the CA certificate (e.g. "ca.crt"). Useful when the
  client connects with `sslmode=verify-ca` or `sslmode=verify-full`.
  Default is empty.

* **caSecretName**
  By setting the `caSecretName` value, the ca certificate file defined by the
  `caFile` will be fetched from this secret instead of `secretName` above.
  This secret has to hold a file with that name in its root.

  Optionally one can provide full path for any of them. By default it is
  relative to the "/tls/", which is mount path of the tls secret.
  If `caSecretName` is defined, the ca.crt path is relative to "/tlsca/",
  otherwise to the same "/tls/".
