[DPE-4257] Async replication UX Improvements (#481)

* Syncing the UX with MySQL

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Fix failover and set-secret behaviour

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Improve statuses

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Fix app status set

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Fix model switch

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Fix config integration test

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

* Fix backups integration test

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

---------

Signed-off-by: Marcelo Henrique Neppel <[email protected]>

Author: marceloneppel

actions.yaml

@@ -11,6 +11,13 @@ create-backup:
         Differential backup is a copy only of changed data since the last full backup.
         Incremental backup is a copy only of changed data since the last backup (any type).
         Possible values - full, differential, incremental.
+create-replication:
+  description: Set up asynchronous replication between two clusters.
+  params:
+    name:
+      type: string
+      description: The name of the replication (defaults to 'default').
+      default: default
 get-primary:
   description: Get the unit which is the primary/leader in the replication.
 get-password:
@@ -25,10 +32,10 @@ list-backups:
   description: Lists backups in s3 storage.
 pre-upgrade-check:
   description: Run necessary pre-upgrade checks and preparations before executing a charm refresh.
-promote-cluster:
+promote-to-primary:
   description: Promotes the cluster of choice to a primary cluster. Must be ran against the leader unit.
   params:
-    force-promotion:
+    force:
       type: boolean
       description: Force the promotion of a cluster when there is already a primary cluster.
 restore:

metadata.yaml

@@ -26,8 +26,8 @@ peers:
     interface: upgrade
 
 provides:
-  async-primary:
-    interface: async_replication
+  replication-offer:
+    interface: postgresql_async
     limit: 1
     optional: true
   database:
@@ -41,8 +41,8 @@ provides:
     limit: 1
 
 requires:
-  async-replica:
-    interface: async_replication
+  replication:
+    interface: postgresql_async
     limit: 1
     optional: true
   certificates:

src/charm.py

@@ -90,7 +90,11 @@
     USER,
     USER_PASSWORD_KEY,
 )
-from relations.async_replication import PostgreSQLAsyncReplication
+from relations.async_replication import (
+    REPLICATION_CONSUMER_RELATION,
+    REPLICATION_OFFER_RELATION,
+    PostgreSQLAsyncReplication,
+)
 from relations.db import EXTENSIONS_BLOCKING_MESSAGE, DbProvides
 from relations.postgresql_provider import PostgreSQLProvider
 from upgrade import PostgreSQLUpgrade, get_postgresql_dependencies_model
@@ -1222,15 +1226,42 @@ def _on_set_password(self, event: ActionEvent) -> None:
             )
             return
 
-        # Update the password in the PostgreSQL instance.
-        try:
-            self.postgresql.update_user_password(username, password)
-        except PostgreSQLUpdateUserPasswordError as e:
-            logger.exception(e)
+        replication_offer_relation = self.model.get_relation(REPLICATION_OFFER_RELATION)
+        if (
+            replication_offer_relation is not None
+            and not self.async_replication.is_primary_cluster()
+        ):
+            # Update the password in the other cluster PostgreSQL primary instance.
+            other_cluster_endpoints = self.async_replication.get_all_primary_cluster_endpoints()
+            other_cluster_primary = self._patroni.get_primary(
+                alternative_endpoints=other_cluster_endpoints
+            )
+            other_cluster_primary_ip = [
+                replication_offer_relation.data[unit].get("private-address")
+                for unit in replication_offer_relation.units
+                if unit.name.replace("/", "-") == other_cluster_primary
+            ][0]
+            try:
+                self.postgresql.update_user_password(
+                    username, password, database_host=other_cluster_primary_ip
+                )
+            except PostgreSQLUpdateUserPasswordError as e:
+                logger.exception(e)
+                event.fail("Failed changing the password.")
+                return
+        elif self.model.get_relation(REPLICATION_CONSUMER_RELATION) is not None:
             event.fail(
-                "Failed changing the password: Not all members healthy or finished initial sync."
+                "Failed changing the password: This action can be ran only in the cluster from the offer side."
             )
             return
+        else:
+            # Update the password in this cluster PostgreSQL primary instance.
+            try:
+                self.postgresql.update_user_password(username, password)
+            except PostgreSQLUpdateUserPasswordError as e:
+                logger.exception(e)
+                event.fail("Failed changing the password.")
+                return
 
         # Update the password in the secret store.
         self.set_secret(APP_SCOPE, f"{username}-password", password)
@@ -1239,9 +1270,6 @@ def _on_set_password(self, event: ActionEvent) -> None:
         # Other units Patroni configuration will be reloaded in the peer relation changed event.
         self.update_config()
 
-        # Update the password in the async replication data.
-        self.async_replication.update_async_replication_data()
-
         event.set_results({"password": password})
 
     def _on_update_status(self, _) -> None:
@@ -1357,7 +1385,7 @@ def _set_primary_status_message(self) -> None:
             if self._patroni.get_primary(unit_name_pattern=True) == self.unit.name:
                 self.unit.status = ActiveStatus("Primary")
             elif self.is_standby_leader:
-                self.unit.status = ActiveStatus("Standby Leader")
+                self.unit.status = ActiveStatus("Standby")
             elif self._patroni.member_started:
                 self.unit.status = ActiveStatus()
         except (RetryError, ConnectionError) as e:

src/cluster.py

@@ -230,19 +230,20 @@ def get_member_status(self, member_name: str) -> str:
                         return member["state"]
         return ""
 
-    def get_primary(self, unit_name_pattern=False) -> str:
+    def get_primary(self, unit_name_pattern=False, alternative_endpoints: List[str] = None) -> str:
         """Get primary instance.
 
         Args:
             unit_name_pattern: whether to convert pod name to unit name
+            alternative_endpoints: list of alternative endpoints to check for the primary.
 
         Returns:
             primary pod or unit name.
         """
         # Request info from cluster endpoint (which returns all members of the cluster).
         for attempt in Retrying(stop=stop_after_attempt(2 * len(self.peers_ips) + 1)):
             with attempt:
-                url = self._get_alternative_patroni_url(attempt)
+                url = self._get_alternative_patroni_url(attempt, alternative_endpoints)
                 cluster_status = requests.get(
                     f"{url}/{PATRONI_CLUSTER_STATUS_ENDPOINT}",
                     verify=self.verify,
@@ -301,12 +302,18 @@ def get_sync_standby_names(self) -> List[str]:
                         sync_standbys.append("/".join(member["name"].rsplit("-", 1)))
         return sync_standbys
 
-    def _get_alternative_patroni_url(self, attempt: AttemptManager) -> str:
+    def _get_alternative_patroni_url(
+        self, attempt: AttemptManager, alternative_endpoints: List[str] = None
+    ) -> str:
         """Get an alternative REST API URL from another member each time.
 
         When the Patroni process is not running in the current unit it's needed
         to use a URL from another cluster member REST API to do some operations.
         """
+        if alternative_endpoints is not None:
+            return self._patroni_url.replace(
+                self.unit_ip, alternative_endpoints[attempt.retry_state.attempt_number - 1]
+            )
         attempt_number = attempt.retry_state.attempt_number
         if attempt_number > 1:
             url = self._patroni_url