From: Tuukka Lehtonen <tuukka.lehtonen@semantum.fi>
Date: Mon, 3 Apr 2017 12:10:34 +0000 (+0300)
Subject: Database backwards compatibility fix for fail-safe import changes
X-Git-Tag: v1.29.0~122
X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=commitdiff_plain;h=687db8141c8c5520a8aab98f78c9ca8c3609141f;p=simantics%2Fplatform.git

Database backwards compatibility fix for fail-safe import changes

To keep databases created before Mar 30 18:39 compatible with the
current git master version.

refs #7016

Change-Id: Ic327809eae90d01d115cfb880a33b9dc37051a36
---

diff --git a/bundles/org.simantics.graph.db/src/org/simantics/graph/db/CoreInitialization.java b/bundles/org.simantics.graph.db/src/org/simantics/graph/db/CoreInitialization.java
index 096f0a00f..b64149032 100644
--- a/bundles/org.simantics.graph.db/src/org/simantics/graph/db/CoreInitialization.java
+++ b/bundles/org.simantics.graph.db/src/org/simantics/graph/db/CoreInitialization.java
@@ -28,6 +28,10 @@ public class CoreInitialization {
 	}
 
 	static {
+		// IMPORTANT NOTICE:
+		// DO NOT alter the order of these definitions in any way
+		// unless you deliberately want to make the system incompatible
+		// with databases that have been created before changing these.
 		addLayer0Builtin("InstanceOf");
 		addLayer0Builtin("Inherits");
 		addLayer0Builtin("SubrelationOf");
@@ -38,7 +42,6 @@ public class CoreInitialization {
 
 		addLayer0Builtin("ConsistsOf");
 		addLayer0Builtin("PartOf");
-		addLayer0Builtin("ExternalEntity");
 
 		addLayer0Builtin("String");
 		addLayer0Builtin("Library");
@@ -50,7 +53,33 @@ public class CoreInitialization {
 		addLayer0Builtin("HasPredicateInverse");
 		addLayer0Builtin("HasObject");
 
+		// #7016: This bogus URI replaces the builtin entry
+		// that was originally http://Projects.
+		//
+		// addBuiltin("http://Projects") was removed because its existence
+		// resulted in a non-functioning URI space because:
+		//
+		// 1. http://Projects was added as a "built-in resource" when the database
+		//    is first initialized which means that ReadGraph.getResource("http://Projects")
+		//    would succeed even when the resource was not yet properly imported
+		//    from the project ontology.
+		//
+		// 2. When the project ontology is imported, a new resource is
+		//    created to represent http://Projects instead of using the existing
+		//    uninitialized "built-in resource". The L0.ExternalEntity changes made
+		//    to the standard transferable graph import in this patch caused the
+		//    code to find the built-in resource for "http://Projects" and think
+		//    that it has to be a resource that's already properly initialized.
+		//    This led to the TG import not initializing the resource at all.
+		//    Previously there was a bug here as well but it was hidden by the fact
+		//    that the system would import the actual/new "http://Projects"
+		//    resource from the ontology anyway. This effectively left the
+		//    uninitialized built-in resource just hanging in the database as
+		//    trash.
+		//addBuiltin("http://Projects");
+		addBuiltin("75e23fb39121b4b37cf2e6a26ccb34c52f77522d-do-not-remove");
 		addBuiltin("http:/");
+		addLayer0Builtin("ExternalEntity");
 	}
 
     public static void initializeBuiltins(Session session) throws DatabaseException {