From f3c207528e310b9312f71e34f6bad2c48d3bee22 Mon Sep 17 00:00:00 2001
From: Michael Hoennig <michael@hoennig.de>
Date: Mon, 6 May 2019 18:42:11 +0200
Subject: [PATCH] general historicization table+function for Postgres

---
 .../historicization/historicization.xml       | 46 +++++++++++++++++++
 .../resources/config/liquibase/master.xml     |  9 +++-
 2 files changed, 54 insertions(+), 1 deletion(-)
 create mode 100644 src/main/resources/config/liquibase/historicization/historicization.xml

diff --git a/src/main/resources/config/liquibase/historicization/historicization.xml b/src/main/resources/config/liquibase/historicization/historicization.xml
new file mode 100644
index 00000000..9f5f515d
--- /dev/null
+++ b/src/main/resources/config/liquibase/historicization/historicization.xml
@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="utf-8"?>
+<databaseChangeLog
+    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
+    xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.5.xsd
+                        http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd">
+
+    <changeSet id="20190506000000-1" author="mhierweck,mhoennig" dbms="postgresql">
+        <createTable tableName="history">
+
+            <column name="history_transaction" type="bigint">
+                <constraints primaryKey="true" nullable="false"/>
+            </column>
+
+            <column name="history_timestamp" type="timestamp">
+                <constraints nullable="false" />
+            </column>
+
+        </createTable>
+
+    </changeSet>
+
+    <changeSet id="20190506000000-2" author="mhierweck,mhoennig" dbms="postgresql">
+        <createProcedure>
+            CREATE OR REPLACE FUNCTION historicize()
+                RETURNS trigger
+            AS $$
+                BEGIN
+                    IF (TG_OP = 'INSERT') OR (TG_OP = 'UPDATE') THEN
+                        EXECUTE 'INSERT INTO history VALUES (txid_current(), now()) ON CONFLICT DO NOTHING';
+                        EXECUTE format('INSERT INTO %I_history VALUES (DEFAULT, txid_current(), False, $1.*)', TG_TABLE_NAME) USING NEW;
+                        RETURN NEW;
+                    ELSE -- assuming TG_OP = 'DELETE'
+                        EXECUTE 'INSERT INTO history VALUES (txid_current(), now()) ON CONFLICT DO NOTHING';
+                        EXECUTE format('INSERT INTO %I_history VALUES (DEFAULT, txid_current(), True, $1.*)', TG_TABLE_NAME) USING OLD;
+                        RETURN OLD;
+                    END IF;
+                END;
+            $$
+            LANGUAGE plpgsql;
+        </createProcedure>
+    </changeSet>
+
+
+</databaseChangeLog>
diff --git a/src/main/resources/config/liquibase/master.xml b/src/main/resources/config/liquibase/master.xml
index c4daff8a..9842d7a3 100644
--- a/src/main/resources/config/liquibase/master.xml
+++ b/src/main/resources/config/liquibase/master.xml
@@ -3,6 +3,8 @@
     xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.5.xsd">
+
+    <!-- JHipster generated entity table changesets -->
     <include file="config/liquibase/changelog/00000000000000_initial_schema.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/changelog/20190430152136_added_entity_Customer.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/changelog/20190430152137_added_entity_Membership.xml" relativeToChangelogFile="false"/>
@@ -11,6 +13,8 @@
     <include file="config/liquibase/changelog/20190430152140_added_entity_SepaMandate.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/changelog/20190430154711_added_entity_UserRoleAssignment.xml" relativeToChangelogFile="false"/>
     <!-- jhipster-needle-liquibase-add-changelog - JHipster will add liquibase changelogs here -->
+
+    <!-- JHipster generated constraints changesets -->
     <include file="config/liquibase/changelog/20190430152137_added_entity_constraints_Membership.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/changelog/20190430152138_added_entity_constraints_Share.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/changelog/20190430152139_added_entity_constraints_Asset.xml" relativeToChangelogFile="false"/>
@@ -18,7 +22,10 @@
     <include file="config/liquibase/changelog/20190430154711_added_entity_constraints_UserRoleAssignment.xml" relativeToChangelogFile="false"/>
     <!-- jhipster-needle-liquibase-add-constraints-changelog - JHipster will add liquibase constraints changelogs here -->
 
-    <!-- sample data -->
+    <!-- historicization -->
+    <include file="config/liquibase/historicization/historicization.xml" relativeToChangelogFile="false"/>
+
+    <!-- sample data. comes after historicization triggers, historicization applies -->
     <include file="config/liquibase/sample-data/customers.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/sample-data/memberships.xml" relativeToChangelogFile="false"/>
     <include file="config/liquibase/sample-data/shares.xml" relativeToChangelogFile="false"/>