Migration functions - release

.bumpversion.cfg

@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 1.9.0
+current_version = 1.9.1
 commit = False
 tag = False
 

microcosm_eventsource/ddl/array_sort_unique.create.ddl

@@ -0,0 +1,10 @@
+/*
+ * array_sort_unique(ANYARRAY)
+ *
+ * Return sorted and unique array
+ */
+CREATE OR REPLACE FUNCTION array_sort_unique (ANYARRAY)
+RETURNS ANYARRAY LANGUAGE SQL
+AS $$
+SELECT ARRAY(SELECT DISTINCT unnest($1) ORDER BY 1)
+$$;

microcosm_eventsource/ddl/array_sort_unique.drop.ddl

@@ -0,0 +1 @@
+DROP FUNCTION IF EXISTS array_sort_unique (ANYARRAY);

microcosm_eventsource/ddl/proc_event_type_delete.create.ddl

@@ -0,0 +1,42 @@
+/*
+ * proc_event_type_delete(table_name, old_event_type, model_id_row_name)
+ *
+ * Should be only used by data migrations scripts.
+ * Delete events with old_event_type and remove it from states,
+ * Must pass model_id_row_name - the row name that links to the parent model
+ * (Example: for company_event table, the model_id_row_name should be company_id)
+ *
+ * Example:
+ * SELECT proc_event_type_delete('task_event', 'SCHEDULED', 'task_id');
+ *
+ * Details:
+ * - Updates parent_id of relevant child events
+ * - Updates the state column (Ensures that the state is sorted and has unique events)
+ * - Does not promise valid events or transitions.
+ * - Cannot be used if model.__unique_parent__ is set to False (missing table_names_parent_id_key constraint),
+ */
+CREATE OR REPLACE FUNCTION proc_event_type_delete(
+    table_name regclass,
+    old_event_type character varying(255),
+    model_id_row_name character varying(255)) RETURNS void AS
+$func$
+BEGIN
+    EXECUTE format(
+        '
+            CREATE TEMP TABLE events_to_remove_%%1$s_%%2$s AS (
+                SELECT id
+                FROM %%1$s
+                WHERE event_type = ''%%2$s''
+            );
+            SELECT proc_events_delete(''%%1$s'', ''events_to_remove_%%1$s_%%2$s'', ''%%3$s'');
+
+            UPDATE %%1$s
+            SET state = array_remove(state, ''%%2$s'')
+            WHERE ''%%2$s'' = ANY(state);
+        ',
+        table_name,
+        old_event_type,
+        model_id_row_name
+    );
+END
+$func$  LANGUAGE plpgsql;

microcosm_eventsource/ddl/proc_event_type_delete.drop.ddl

@@ -0,0 +1 @@
+DROP FUNCTION IF EXISTS proc_event_type_delete(regclass, character varying(255), character varying(255));

microcosm_eventsource/ddl/proc_event_type_replace.create.ddl

@@ -0,0 +1,37 @@
+/*
+ * proc_event_type_replace(table_name, old_event_type, new_event_type)
+ *
+ * Should be only used by data migrations scripts.
+ * Replaces old_event_type with new_event_type in table_name table,
+ *
+ * Example:
+ * SELECT proc_event_type_replace('task_event', 'SCHEDULED', 'CANCELED');
+ *
+ * Details:
+ * - Updates the event_type column
+ * - Updates the state column (Ensures that the state is sorted and has unique events)
+ * - Does not promise valid events or transitions.
+ */
+
+CREATE OR REPLACE FUNCTION proc_event_type_replace(
+    table_name regclass,
+    old_event_type character varying(255),
+    new_event_type character varying(255)) RETURNS void AS
+$func$
+BEGIN
+    EXECUTE format(
+        '
+            UPDATE %%1$s
+            SET event_type = ''%%3$s''
+            WHERE event_type = ''%%2$s'';
+
+            UPDATE %%1$s
+            SET state = array_sort_unique(array_replace(state, ''%%2$s'', ''%%3$s''))
+            WHERE ''%%2$s'' = ANY(state);
+        ',
+        table_name,
+        old_event_type,
+        new_event_type
+    );
+END
+$func$  LANGUAGE plpgsql;

microcosm_eventsource/ddl/proc_event_type_replace.drop.ddl

@@ -0,0 +1 @@
+DROP FUNCTION IF EXISTS proc_event_type_replace(regclass, character varying(255), character varying(255));

microcosm_eventsource/ddl/proc_events_delete.create.ddl

@@ -0,0 +1,109 @@
+/*
+ * proc_events_delete(table_name, events_to_delete_table_name, model_id_row_name)
+ *
+ * Should be only used by data migrations scripts.
+ * Deletes events from table table_name - a valid microcosm-event-source event table.
+ * Pass the events to delete as column id from table events_to_delete_table_name.
+ * Must pass model_id_row_name - the row name that links to the parent model
+ * (Example: for company_event table, the model_id_row_name should be company_id)
+ *
+ * Example:
+ * CREATE TEMP TABLE events_to_remove AS (SELECT id FROM task_event WHERE event_type='SCHEDULED');
+ * SELECT proc_events_delete('task_event', 'events_to_remove', 'task_id');
+ *
+ * Details:
+ * - Won't update the state (see: proc_event_type_delete function)
+ * - Deletes the relevant events
+ * - Updates the parent_id of the child events
+ * - Cannot be used if model.__unique_parent__ is set to False (missing table_names_parent_id_key constraint),
+ *   If thats the case - use proc_events_delete_with_no_parent_id_constraint function instead.
+ */
+CREATE OR REPLACE FUNCTION proc_events_delete(
+    table_name regclass,
+    events_to_delete_table_name regclass,
+    model_id_row_name character varying(255)) RETURNS void AS
+$func$
+BEGIN
+    EXECUTE format(
+        '
+            ALTER TABLE %%1$s DROP CONSTRAINT %%1$s_parent_id_key;
+            SELECT proc_events_delete_with_no_parent_id_constraint(''%%1$s'', ''%%2$s'', ''%%3$s'');
+            ALTER TABLE %%1$s ADD CONSTRAINT %%1$s_parent_id_key UNIQUE (parent_id);
+        ',
+        table_name,
+        events_to_delete_table_name,
+        model_id_row_name
+    );
+END
+$func$  LANGUAGE plpgsql;
+
+
+/*
+ * proc_events_delete_with_no_parent_id_constraint(table_name, events_to_delete_table_name, model_id_row_name)
+ *
+ * Should be only used by data migrations scripts.
+ * Same as proc_events_delete function but for use if model.__unique_parent__ is set to False
+ * (missing table_names_parent_id_key constraint),
+ */
+CREATE OR REPLACE FUNCTION proc_events_delete_with_no_parent_id_constraint(
+    table_name regclass,
+    events_to_delete_table_name regclass,
+    model_id_row_name character varying(255)) RETURNS void AS
+$func$
+BEGIN
+    EXECUTE format(
+        '
+            -- Temporary drop the constraint, bring it back before the end of the transaction.
+            ALTER TABLE %%1$s DROP CONSTRAINT %%1$s_parent_id_fkey;
+
+            -- Updates parent_id of events if the current parent_id is going to be deleted.
+            -- Handle the case that the new parent_id is not the parent_id of the current parent. 
+            -- (For example from the events chain a->b->c->d, both events b and c are going to be deleted) 
+            -- Skip events that are going to be deleted anyway.
+            -- Skip the new"top events" - events that are going to have no parent id.
+            WITH child_events AS (
+                SELECT child_event.id, child_event.clock, child_event.%%3$s
+                FROM %%1$s AS child_event
+                JOIN %%2$s AS parent_event
+                ON parent_event.id = child_event.parent_id
+                LEFT JOIN %%2$s AS events_to_avoid
+                ON events_to_avoid.id = child_event.id
+                WHERE events_to_avoid.id is null
+            ),
+            new_child_events_parents AS (
+                SELECT distinct on (child_events.clock)
+                    child_events.id AS child_event_id,
+                    new_parent.id AS new_parent_id
+                FROM %%1$s AS new_parent
+                RIGHT JOIN child_events
+                ON new_parent.%%3$s = child_events.%%3$s
+                AND new_parent.clock < child_events.clock
+                LEFT JOIN %%2$s AS events_to_avoid
+                ON events_to_avoid.id = new_parent.id
+                WHERE events_to_avoid.id is null
+                ORDER BY child_events.clock, new_parent.clock desc
+            )
+            UPDATE %%1$s
+            SET parent_id = new_child_events_parents.new_parent_id
+            FROM new_child_events_parents
+            WHERE %%1$s.id = new_child_events_parents.child_event_id;
+
+            -- Delete the events
+            DELETE FROM %%1$s
+            USING %%2$s
+            WHERE %%1$s.id = %%2$s.id;
+
+            -- Set null parent id to the new "top events".
+            UPDATE %%1$s
+            SET parent_id = null
+            FROM %%2$s
+            WHERE %%1$s.parent_id = %%2$s.id;
+
+            ALTER TABLE %%1$s ADD CONSTRAINT %%1$s_parent_id_fkey FOREIGN KEY (parent_id) REFERENCES %%1$s(id);
+        ',
+        table_name,
+        events_to_delete_table_name,
+        model_id_row_name
+    );
+END
+$func$  LANGUAGE plpgsql;

microcosm_eventsource/ddl/proc_events_delete.drop.ddl

@@ -0,0 +1,2 @@
+DROP FUNCTION IF EXISTS proc_events_delete(regclass, regclass, character varying(255));
+DROP FUNCTION IF EXISTS proc_events_delete_with_no_parent_id_constraint(regclass, character varying(255), character varying(255));

microcosm_eventsource/func.py

@@ -19,12 +19,26 @@ def load_ddl(name, action):
 listen(
     Model.metadata,
     "after_create",
-    DDL(load_ddl("last_agg_sfunc", "create") + load_ddl("last_agg", "create")),
+    DDL(
+        load_ddl("array_sort_unique", "create") +
+        load_ddl("proc_events_delete", "create") +
+        load_ddl("proc_event_type_delete", "create") +
+        load_ddl("last_agg_sfunc", "create") +
+        load_ddl("last_agg", "create") +
+        load_ddl("proc_event_type_replace", "create")
+    ),
 )
 listen(
     Model.metadata,
     "after_drop",
-    DDL(load_ddl("last_agg", "drop") + load_ddl("last_agg_sfunc", "drop")),
+    DDL(
+        load_ddl("array_sort_unique", "drop") +
+        load_ddl("proc_events_delete", "drop") +
+        load_ddl("proc_event_type_delete", "drop") +
+        load_ddl("last_agg", "drop") +
+        load_ddl("last_agg_sfunc", "drop") +
+        load_ddl("proc_event_type_replace", "drop")
+    ),
 )