From d8bc0cb41efa98909ed4eebda2fbd0e8d8157028 Mon Sep 17 00:00:00 2001
From: miker <miker@dcc99617-32d9-48b4-a31d-7c20da2025e4>
Date: Wed, 27 Apr 2011 15:24:54 +0000
Subject: [PATCH] support for depracate/supersede tracking of upgrade scripts,
 and automatic rejection of conflicting scripts

git-svn-id: svn://svn.open-ils.org/ILS/trunk@20341 dcc99617-32d9-48b4-a31d-7c20da2025e4
---
 Open-ILS/src/sql/Pg/002.schema.config.sql     |  2 +-
 .../0526.schema.upgrade-dep-tracking.sql      | 79 +++++++++++++++++++
 2 files changed, 80 insertions(+), 1 deletion(-)
 create mode 100644 Open-ILS/src/sql/Pg/upgrade/0526.schema.upgrade-dep-tracking.sql

diff --git a/Open-ILS/src/sql/Pg/002.schema.config.sql b/Open-ILS/src/sql/Pg/002.schema.config.sql
index 0ca0d89084..20045c2516 100644
--- a/Open-ILS/src/sql/Pg/002.schema.config.sql
+++ b/Open-ILS/src/sql/Pg/002.schema.config.sql
@@ -57,7 +57,7 @@ CREATE TABLE config.upgrade_log (
     install_date    TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW()
 );
 
-INSERT INTO config.upgrade_log (version) VALUES ('0524'); -- phasefx
+INSERT INTO config.upgrade_log (version) VALUES ('0526'); -- phasefx
 
 CREATE TABLE config.bib_source (
 	id		SERIAL	PRIMARY KEY,
diff --git a/Open-ILS/src/sql/Pg/upgrade/0526.schema.upgrade-dep-tracking.sql b/Open-ILS/src/sql/Pg/upgrade/0526.schema.upgrade-dep-tracking.sql
new file mode 100644
index 0000000000..45a0388e49
--- /dev/null
+++ b/Open-ILS/src/sql/Pg/upgrade/0526.schema.upgrade-dep-tracking.sql
@@ -0,0 +1,79 @@
+BEGIN;
+
+INSERT INTO config.upgrade_log (version) VALUES ('0526'); --miker
+
+CREATE TABLE config.db_patch_dependencies (
+  db_patch      TEXT PRIMARY KEY,
+  supersedes    TEXT[],
+  deprecates    TEXT[],
+  EXCLUDE ( supersedes WITH &&, deprecates WITH && )
+);
+
+ALTER TABLE config.upgrade_log
+    ADD COLUMN applied_to TEXT;
+
+-- List applied db patches that are deprecated by (and block the application of) my_db_patch
+CREATE OR REPLACE FUNCTION evergreen.upgrade_list_applied_deprecates ( my_db_patch TEXT ) RETURNS SETOF TEXT AS $$
+    SELECT  DISTINCT l.version
+      FROM  config.upgrade_log l
+            JOIN config.db_patch_dependencies d ON (l.version::TEXT[] && d.deprecates)
+      WHERE d.db_patch = my_db_patch 
+$$ LANGUAGE SQL;
+
+-- List applied db patches that are superseded by (and block the application of) my_db_patch
+CREATE OR REPLACE FUNCTION evergreen.upgrade_list_applied_supersedes ( my_db_patch TEXT ) RETURNS SETOF TEXT AS $$
+    SELECT  DISTINCT l.version
+      FROM  config.upgrade_log l
+            JOIN config.db_patch_dependencies d ON (l.version::TEXT[] && d.supersedes)
+      WHERE d.db_patch = my_db_patch 
+$$ LANGUAGE SQL;
+
+-- List applied db patches that deprecates (and block the application of) my_db_patch
+CREATE OR REPLACE FUNCTION evergreen.upgrade_list_applied_superseded ( my_db_patch TEXT ) RETURNS TEXT AS $$
+    SELECT  db_patch
+      FROM  config.db_patch_dependencies
+      WHERE my_db_patch::TEXT[] && deprecates 
+$$ LANGUAGE SQL;
+
+-- List applied db patches that supersedes (and block the application of) my_db_patch
+CREATE OR REPLACE FUNCTION evergreen.upgrade_list_applied_superseded ( my_db_patch TEXT ) RETURNS TEXT AS $$
+    SELECT  db_patch
+      FROM  config.db_patch_dependencies
+      WHERE my_db_patch::TEXT[] && supersedes 
+$$ LANGUAGE SQL;
+
+-- Make sure that no deprecated or superseded db patches are currently applied
+CREATE OR REPLACE FUNCTION evergreen.upgrade_verify_no_dep_conflicts ( my_db_patch TEXT ) RETURNS BOOL AS $$
+    SELECT  COUNT(*) = 0
+      FROM  (SELECT * FROM evergreen.upgrade_list_applied_deprecates( my_db_patch )
+                UNION
+             SELECT * FROM evergreen.upgrade_list_applied_supersedes( my_db_patch )
+                UNION
+             SELECT * FROM evergreen.upgrade_list_applied_deprecated( my_db_patch )
+                UNION
+             SELECT * FROM evergreen.upgrade_list_applied_superseded( my_db_patch ))x
+$$ LANGUAGE SQL;
+
+-- Raise an exception if there are, in fact, dep/sup confilct
+CREATE OR REPLACE FUNCTION evergreen.upgrade_deps_block_check ( my_db_patch TEXT, my_applied_to TEXT ) RETURNS BOOL AS $$
+BEGIN
+    IF NOT evergreen.upgrade_verify_no_dep_conflicts( my_db_patch ) THEN
+        RAISE EXCEPTION '
+Upgrade script % can not be applied:
+  applied deprecated scripts %
+  applied superseded scripts %
+  deprecated by %
+  superseded by %',
+            my_db_patch,
+            ARRAY_ACUM(evergreen.upgrade_list_applied_deprecates(my_db_patch)),
+            ARRAY_ACUM(evergreen.upgrade_list_applied_supersedes(my_db_patch)),
+            evergreen.upgrade_list_applied_deprecated(my_db_patch),
+            evergreen.upgrade_list_applied_superseded(my_db_patch);
+    END IF;
+
+    INSERT INTO config.upgrade_log (version, applied_to) VALUES (my_db_patch, my_applied_to);
+    RETURN TRUE;
+END;
+$$ LANGUAGE SQL;
+
+COMMIT;
-- 
2.43.2