patroni.dcs.kubernetes module¶

class patroni.dcs.kubernetes.CoreV1ApiProxy(use_endpoints: Optional[bool] = False, bypass_api_service: Optional[bool] = False)¶

Bases: object

Proxy class to work with k8s_client.CoreV1Api() object

configure_retriable_http_codes(retriable_http_codes: List[int]) → None¶

configure_timeouts(loop_wait: int, retry_timeout: Union[int, float], ttl: int) → None¶

refresh_api_servers_cache() → None¶

use_endpoints¶

class patroni.dcs.kubernetes.K8sClient¶

Bases: object

class ApiClient(bypass_api_service: Optional[bool] = False)¶

Bases: object

api_servers_cache¶

call_api(method: str, path: str, headers: Optional[Dict[str, str]] = None, body: Optional[Any] = None, _retry: Optional[patroni.utils.Retry] = None, _preload_content: bool = True, _request_timeout: Optional[float] = None, **kwargs) → Union[urllib3.response.HTTPResponse, patroni.dcs.kubernetes.K8sObject]¶

refresh_api_servers_cache() → None¶

request(retry: Optional[patroni.utils.Retry], method: str, path: str, timeout: Union[int, float, Tuple[Union[int, float], Union[int, float]], urllib3.util.timeout.Timeout, None] = None, **kwargs) → urllib3.response.HTTPResponse¶

set_api_servers_cache_ttl(ttl: int) → None¶

set_base_uri(value: str) → None¶

set_read_timeout(timeout: Union[int, float]) → None¶

class CoreV1Api(api_client: Optional[K8sClient.ApiClient] = None)¶: Bases: object

class rest¶

Bases: object

exception ApiException(status: Optional[int] = None, reason: Optional[str] = None, http_resp: Optional[urllib3.response.HTTPResponse] = None)¶: Bases: Exception

class patroni.dcs.kubernetes.K8sConfig¶

Bases: object

exception ConfigException¶: Bases: Exception

headers¶

load_incluster_config(ca_certs: str = '/var/run/secrets/kubernetes.io/serviceaccount/ca.crt', token_refresh_interval: datetime.timedelta = datetime.timedelta(seconds=60)) → None¶

load_kube_config(context: Optional[str] = None) → None¶

server¶

exception patroni.dcs.kubernetes.K8sConnectionFailed¶: Bases: patroni.dcs.kubernetes.K8sException

exception patroni.dcs.kubernetes.K8sException¶: Bases: Exception

class patroni.dcs.kubernetes.K8sObject(kwargs: Dict[str, Any])¶

Bases: object

get(name: str, default: Optional[Any] = None) → Optional[Any]¶

to_dict() → Dict[str, Any]¶

class patroni.dcs.kubernetes.Kubernetes(config: Dict[str, Any])¶

Bases: patroni.dcs.AbstractDCS

attempt_to_acquire_leader() → bool¶

Attempt to acquire leader lock.

Note

This method should create /leader key with the value _name.

The key must be created atomically. In case the key already exists it should not be overwritten and False must be returned.

If key creation fails due to DCS not being accessible or because it is not able to process requests (hopefully temporary), the DCSError exception should be raised.

Returns:	`True` if key has been created successfully.

cancel_initialization() → bool¶

Removes the initialize key for a cluster.

Returns:	`True` if successfully committed to DCS.

client_path(path: str) → str¶

Construct the absolute key name from appropriate parts for the DCS type.

Parameters:	path – The key name within the current Patroni cluster.
Returns:	absolute key name for the current Patroni cluster.

static compare_ports(p1: patroni.dcs.kubernetes.K8sObject, p2: patroni.dcs.kubernetes.K8sObject) → bool¶

delete_cluster(*args, **kwargs) → Any¶

delete_leader(last_lsn: Optional[int] = None) → bool¶

Update optime/leader and voluntarily remove leader key from DCS.

This method should remove leader key if current instance is the leader.

Parameters:	last_lsn – latest checkpoint location in bytes.
Returns:	boolean result of called abstract `_delete_leader()`.

delete_sync_state(version: Optional[str] = None) → bool¶

Patch annotations of $SCOPE-sync Endpoint or ConfigMap with empty values.

Effectively it removes “leader” and “sync_standby” annotations from the object. :param version: last known resource_version for conditional update of the object :returns: True if “delete” was successful

get_citus_coordinator() → Optional[patroni.dcs.Cluster]¶

Load the Patroni cluster for the Citus Coordinator.

Note

This method is only executed on the worker nodes (group!=0) to find the coordinator.

Returns:	Select `Cluster` instance associated with the Citus Coordinator group ID.

initialize(create_new: bool = True, sysid: str = '') → bool¶

Race for cluster initialization.

This method should atomically create initialize key and return True, otherwise it should return False.

Parameters:	create_new – `False` if the key should already exist (in the case we are setting the system_id). sysid – PostgreSQL cluster system identifier, if specified, is written to the key.
Returns:	`True` if key has been created successfully.

leader_path¶: Get the client path for leader.

manual_failover(leader: Optional[str], candidate: Optional[str], scheduled_at: Optional[datetime.datetime] = None, version: Optional[str] = None) → bool¶

Prepare dictionary with given values and set /failover key in DCS.

Parameters:	leader – value to set for `leader`. candidate – value to set for `member`. scheduled_at – value converted to ISO date format for `scheduled_at`. version – for conditional update of the key/object.
Returns:	`True` if successfully committed to DCS.

static member(pod: patroni.dcs.kubernetes.K8sObject) → patroni.dcs.Member¶

patch_or_create(*args, **kwargs) → Any¶

patch_or_create_config(annotations: Dict[str, Any], resource_version: Optional[str] = None, patch: bool = False, retry: bool = True) → bool¶

reload_config(config: Union[Config, Dict[str, Any]]) → None¶

Handles dynamic config changes.

Either cause by changes in the local configuration file + SIGHUP or by changes of dynamic configuration

retry(method: Callable[[...], Any], *args, **kwargs) → Any¶

set_config_value(value: str, version: Optional[str] = None) → bool¶

Create or update /config key in DCS.

Parameters:	value – new value to set in the `config` key. version – for conditional update of the key/object.
Returns:	`True` if successfully committed to DCS.

set_failover_value(value: str, version: Optional[str] = None) → bool¶: Unused

set_history_value(value: str) → bool¶

Set value for history in DCS.

Parameters:	value – new value of `history` key/object.
Returns:	`True` if successfully committed to DCS.

set_retry_timeout(retry_timeout: int) → None¶: Set the new value for retry_timeout.

set_sync_state_value(value: str, version: Optional[str] = None) → bool¶: Unused

set_ttl(ttl: int) → Optional[bool]¶: Set the new ttl value for DCS keys.

static subsets_changed(last_observed_subsets: List[patroni.dcs.kubernetes.K8sObject], ip: str, ports: List[patroni.dcs.kubernetes.K8sObject]) → bool¶

>>> ip = '1.2.3.4'
>>> a = [k8s_client.V1EndpointAddress(ip=ip)]
>>> s = [k8s_client.V1EndpointSubset(addresses=a)]
>>> Kubernetes.subsets_changed(s, '1.2.3.5', [])
True
>>> s = [k8s_client.V1EndpointSubset(addresses=a, ports=[k8s_client.V1EndpointPort(protocol='TCP', port=1)])]
>>> Kubernetes.subsets_changed(s, '1.2.3.4', [k8s_client.V1EndpointPort(port=5432)])
True
>>> p1 = k8s_client.V1EndpointPort(name='port1', port=1)
>>> p2 = k8s_client.V1EndpointPort(name='port2', port=2)
>>> p3 = k8s_client.V1EndpointPort(name='port3', port=3)
>>> s = [k8s_client.V1EndpointSubset(addresses=a, ports=[p1, p2])]
>>> Kubernetes.subsets_changed(s, ip, [p2, p3])
True
>>> s2 = [k8s_client.V1EndpointSubset(addresses=a, ports=[p2, p1])]
>>> Kubernetes.subsets_changed(s, ip, [p2, p1])
False

take_leader() → bool¶

Establish a new leader in DCS.

Note

This method should create leader key with value of _name and ttl of ttl.

Since it could be called only on initial cluster bootstrap it could create this key regardless, overwriting the key if necessary.

Returns:	`True` if successfully committed to DCS.

touch_member(*args, **kwargs) → Any¶

ttl¶: Get current ttl value.

update_leader(leader: patroni.dcs.Leader, last_lsn: Optional[int], slots: Optional[Dict[str, int]] = None, failsafe: Optional[Dict[str, str]] = None) → bool¶

Update leader key (or session) ttl and optime/leader.

Parameters:	leader – `Leader` object with information about the leader. last_lsn – absolute WAL LSN in bytes. slots – dictionary with permanent slots `confirmed_flush_lsn`. failsafe – if defined dictionary passed to `write_failsafe()`.
Returns:	`True` if `leader` key (or session) has been updated successfully.

watch(leader_version: Optional[str], timeout: float) → bool¶

Sleep if the current node is a leader, otherwise, watch for changes of leader key with a given timeout.

Parameters:	leader_version – version of a leader key. timeout – timeout in seconds.
Returns:	if `True` this will reschedule the next run of the HA cycle.

write_leader_optime(last_lsn: int) → None¶

Write value for WAL LSN to optime annotation of the leader object.

Parameters:	last_lsn – absolute WAL LSN in bytes.

write_sync_state(leader: Optional[str], sync_standby: Optional[Collection[str]], version: Optional[str] = None) → Optional[patroni.dcs.SyncState]¶

Prepare and write annotations to $SCOPE-sync Endpoint or ConfigMap.

Parameters:	leader – name of the leader node that manages /sync key sync_standby – collection of currently known synchronous standby node names version – last known resource_version for conditional update of the object
Returns:	the new `SyncState` object or None

exception patroni.dcs.kubernetes.KubernetesError(value: Any)¶: Bases: patroni.exceptions.DCSError

exception patroni.dcs.kubernetes.KubernetesRetriableException(orig: patroni.dcs.kubernetes.K8sClient.rest.ApiException)¶

Bases: patroni.dcs.kubernetes.ApiException

sleeptime¶

class patroni.dcs.kubernetes.ObjectCache(dcs: patroni.dcs.kubernetes.Kubernetes, func: Callable[[...], Any], retry: patroni.utils.Retry, condition: threading.Condition, name: Optional[str] = None)¶

Bases: threading.Thread

copy() → Dict[str, patroni.dcs.kubernetes.K8sObject]¶

delete(name: str, resource_version: str) → Tuple[bool, Optional[patroni.dcs.kubernetes.K8sObject]]¶

get(name: str) → Optional[patroni.dcs.kubernetes.K8sObject]¶

is_ready() → bool¶: Must be called only when holding the lock on _condition

kill_stream() → None¶

run() → None¶

Method representing the thread’s activity.

You may override this method in a subclass. The standard run() method invokes the callable object passed to the object’s constructor as the target argument, if any, with sequential and keyword arguments taken from the args and kwargs arguments, respectively.

set(name: str, value: patroni.dcs.kubernetes.K8sObject) → Tuple[bool, Optional[patroni.dcs.kubernetes.K8sObject]]¶

patroni.dcs.kubernetes.catch_kubernetes_errors(func: Callable[[...], Any]) → Callable[[...], Any]¶

patroni.dcs.kubernetes.k8s_client¶

patroni.dcs.kubernetes.to_camel_case(value: str) → str¶