Untitled :: Tecnisys Docs

patroni.dcs.raft module

class _patroni.dcs.raft.DynMemberSyncObj(_selfAddress: str | None, partnerAddrs: Collection[ str], conf: SyncObjConf, retry_timeout: int = 10) View on GitHub 

Bases: SyncObj +

__init\\__(selfAddress: str | None, partnerAddrs: Collection[ str], conf: SyncObjConf, retry_timeout: int = 10) → None View on GitHub 

Main SyncObj class, you should inherit your own class from it. +

Parameters: +

onTick(_timeToWait: float = 0.0) View on GitHub 

getMembers(args: Any, callback: Callable[[ Any, Any], Any]) → None View on GitHub 

class _patroni.dcs.raft.KVStoreTTL(_on_ready: Callable[[…], Any] | None, on_set: Callable[[ str, Dict[ str, Any]], None] | None, on_delete: Callable[[ str], None] | None, **config: Any) View on GitHub 

Bases: DynMemberSyncObj +

__check_requirements(_**kwargs: Any_) → bool 

\__expire_keys() → None 

__init\\__(on_ready: Callable[[…], Any] | None, on_set: Callable[[ str, Dict[ str, Any]], None] | None, on_delete: Callable[[ str], None] | None, **config: Any) → None View on GitHub 

Main SyncObj class, you should inherit your own class from it. +

Parameters: +

__pop(_key: str_) → None 

__values_match(_new: Dict[ str, Any]_) → bool 

_autoTickThread() → None View on GitHub 

delete(_key: str, recursive: bool = False, **kwargs: Any) → bool View on GitHub 

delete_v0(_key: str, recursive: bool = False, **kwargs: Any) → bool View on GitHub 

expire(_key: str, value: Dict[ str, Any], callback: Callable[[…], Any] | None = None) → None View on GitHub 

expire_v0(_key: str, value: Dict[ str, Any], callback: Callable[[…], Any] | None = None) → None View on GitHub 

onTick(_timeToWait: float = 0.0) → None View on GitHub 

set(_key: str, value: Dict[ str, Any], **kwargs: Any) → bool | Dict[ str, Any] View on GitHub 

set_v0(_key: str, value: Dict[ str, Any], **kwargs: Any) → bool | Dict[ str, Any] View on GitHub 

delete(key: str, recursive: bool = False, **kwargs: Any) → bool View on GitHub 

destroy() → None View on GitHub 

Correctly destroy SyncObj. Stop autoTickThread, close connections, etc. +

get(key: str, recursive: bool = False) → None | Dict[ str, Any] | Dict[ str, Dict[ str, Any]] View on GitHub 

retry(func: Callable[[…], Any], *args: Any, **kwargs: Any) → Any View on GitHub 

set(key: str, value: str, ttl: int | None = None, handle_raft_error: bool = True, **kwargs: Any) → bool | Dict[ str, Any] View on GitHub 

set_retry_timeout(retry_timeout: int) → None View on GitHub 

startAutoTick() → None View on GitHub 

class _patroni.dcs.raft.Raft(_config: Dict[ str, Any], mpp: AbstractMPP) View on GitHub 

Bases: AbstractDCS +

__init\\__(config: Dict[ str, Any], mpp: AbstractMPP) → None View on GitHub 

Prepare DCS paths, MPP object, initial values for state information and processing dependencies. +

Variables: config – dict, reference to config section of selected DCS. i.e.: zookeeper for zookeeper, etcd for etcd, etc… +

abc_impl = <_abc._abc_data object>_

cluster_from_nodes(_nodes: Dict[ str, Any]) → Cluster View on GitHub 

delete_leader(_leader: Leader) → bool View on GitHub 

Remove leader key from DCS. + This method should remove leader key if current instance is the leader. +

Parameters: leader – Leader object with information about the leader.
Returns: True if successfully committed to DCS. +

load_cluster(_path: str, loader: Callable[[ str], Cluster | Dict[ int, Cluster]]) → Cluster | Dict[ int, Cluster] View on GitHub 

Main abstract method that implements the loading of Cluster instance. + Note

  Internally this method should call the _loader_ method that will build `+Cluster+` object which represents current state and topology of the cluster in DCS. This method supposed to be called only by the `+get_cluster()+` method.
  +
  Parameters:::
  Raise:::
    `+DCSError+` in case of communication problems with DCS. If the current node was running as a primary and exception raised, instance would be demoted.
+

mpp_cluster_loader(_path: str) → Dict[ int, Cluster] View on GitHub 

Load and build all PostgreSQL clusters from a single MPP cluster. +

Parameters: path – the path in DCS where to load Cluster(s) from.
Returns: all MPP groups as dict, with group IDs as keys and Cluster objects as values. +

on_delete(_key: str) → None View on GitHub 

on_set(_key: str, value: Dict[ str, Any]) → None View on GitHub 

postgresql_cluster_loader(_path: str) → Cluster View on GitHub 

Load and build the Cluster object from DCS, which represents a single PostgreSQL cluster. +

Parameters: path – the path in DCS where to load Cluster from.
Returns: Cluster instance. +

update_leader(_leader: Leader) → bool View on GitHub 

Update leader key (or session) ttl. + Note

You have to use CAS (Compare And Swap) operation in order to update leader key, for example for etcd `+prevValue+` parameter must be used.

  If update fails due to DCS not being accessible or because it is not able to process requests (hopefully temporary), the `+DCSError+` exception should be raised.
  +
  Parameters:::
    *leader* – a reference to a current `+leader+` object.
  Returns:::
    `+True+` if `+leader+` key (or session) has been updated successfully.
+

write_failsafe(_value: str) → bool View on GitHub 

Write current cluster topology to DCS that will be used by failsafe mechanism (if enabled). +

Parameters: value – failsafe topology serialized in JSON format.
Returns: True if successfully committed to DCS. +

write_leader_optime(_last_lsn: str) → bool View on GitHub 

Write current WAL LSN into /optime/leader key in DCS. +

Parameters: last_lsn – absolute WAL LSN in bytes.
Returns: True if successfully committed to DCS. +

write_status(_value: str) → bool View on GitHub 

Write current WAL LSN and confirmed_flush_lsn of permanent slots into the /status key in DCS. +

Parameters: value – status serialized in JSON format.
Returns: True if successfully committed to DCS. +

attempt_to_acquire_leader() → bool View on GitHub 

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 View on GitHub 

Removes the initialize key for a cluster. +

Returns: True if successfully committed to DCS. +

delete_cluster() → bool View on GitHub 

Delete cluster from DCS. +

Returns: True if successfully committed to DCS. +

delete_sync_state(version: int | None = None) → bool View on GitHub 

Delete the synchronous state from DCS. +

Parameters: version – for conditional deletion of the key/object.
Returns: True if delete successful. +

initialize(create_new: bool = True, sysid: str = '') → bool View on GitHub 

Race for cluster initialization. + This method should atomically create initialize key and return True, otherwise it should return False. +

Parameters
Returns: True if key has been created successfully. +

static _member(_key: str, value: Dict[ str, Any]) → Member View on GitHub 

reload_config(config: Config | Dict[ str, Any]) → None View on GitHub 

Load and set relevant values from configuration. + Sets loop_wait, ttl and retry_timeout properties. +

Parameters: config – Loaded configuration information object or dictionary of key value pairs. +

set_config_value(value: str, version: int | None = None) → bool View on GitHub 

Create or update /config key in DCS. +

Parameters
Returns: True if successfully committed to DCS. +

set_failover_value(value: str, version: int | None = None) → bool View on GitHub 

Create or update /failover key. +

Parameters
Returns: True if successfully committed to DCS. +

set_history_value(value: str) → bool View on GitHub 

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 View on GitHub 

Set the new value for retry_timeout. +

set_sync_state_value(value: str, version: int | None = None) → int | bool View on GitHub 

Set synchronous state in DCS. +

Parameters
Returns: version of the new object or False in case of error. +

set_ttl(ttl: int) → bool | None View on GitHub 

Set the new ttl value for DCS keys. +

take_leader() → bool View on GitHub 

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(data: Dict[ str, Any]) → bool View on GitHub 

Update member key in DCS. + Note

  This method should create or update key with the name with `+/members/+` + `+_name+` and the value of _data_ in a given DCS.
  +
  Parameters:::
    *data* – information about an instance (including connection strings).
  Returns:::
    `+True+` if successfully committed to DCS.
+

property _ttl: int_

Get current ttl value. +

watch(leader_version: int | None, timeout: float) → bool View on GitHub 

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

Parameters
Returns: if True this will reschedule the next run of the HA cycle.

exception _patroni.dcs.raft.RaftError(_value: Any) View on GitHub 

Bases: DCSError

class _patroni.dcs.raft.SyncObjUtility(_otherNodes: Collection[ str | TCPNode], conf: SyncObjConf, retry_timeout: int = 10) View on GitHub 

Bases: object +

__init\\__(otherNodes: Collection[ str | TCPNode], conf: SyncObjConf, retry_timeout: int = 10) → None View on GitHub : +
executeCommand(command: List[ Any]) → Any View on GitHub : +
getMembers() → List[ str] | None View on GitHub 

class _patroni.dcs.raft._TCPTransport(_syncObj: DynMemberSyncObj, selfNode: TCPNode | None, otherNodes: Collection[TCPNode]) View on GitHub 

Bases: TCPTransport +

__init\\__(syncObj: DynMemberSyncObj, selfNode: TCPNode | None, otherNodes: Collection[TCPNode]) → None View on GitHub 

Initialise the TCP transport. On normal (non-read-only) nodes, this will start a TCP server. On all nodes, it will initiate relevant connections to other nodes. +

Parameters: +

connectIfNecessarySingle(_node: TCPNode) → bool View on GitHub 

Connect to a node if necessary. +

Parameters: node (Node) – node to connect to

patroni.dcs.raft.resolve_host(self: TCPNode) → str | None View on GitHub 

Previous Next

Built with Sphinx using a theme provided by Read the Docs.

Read the Docs v: latest

bugfix-readthedocs

Project Home

+ Builds