Skip non-existent projects when migrating to schema version 108

When migrating to Schema 108 we can safely skip the projects that do
not exist anymore.

List the skipped projects to the console so that they can be safely
removed from the database at a later time.

Change-Id: Ibd84cd96391ceff12777d4ee18204d85849abb5e

1 files changed, 24 insertions, 6 deletions

diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_108.java b/gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_108.java
index cfafb37841..4e76325347 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_108.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_108.java
@@ -14,14 +14,17 @@
 
 package com.google.gerrit.server.schema;
 
+import com.google.common.base.Joiner;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.SetMultimap;
+import com.google.common.collect.Sets;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.Change.Status;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.Project;
+import com.google.gerrit.reviewdb.client.Project.NameKey;
 import com.google.gerrit.reviewdb.client.RefNames;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.git.GitRepositoryManager;
@@ -44,6 +47,7 @@ import java.io.IOException;
 import java.util.Collection;
 import java.util.Map;
 import java.util.Set;
+import java.util.SortedSet;
 
 public class Schema_108 extends SchemaVersion {
   private final GitRepositoryManager repoManager;
@@ -59,7 +63,7 @@ public class Schema_108 extends SchemaVersion {
   protected void migrateData(ReviewDb db, UpdateUI ui) throws OrmException {
     ui.message("Listing all changes ...");
     SetMultimap<Project.NameKey, Change.Id> openByProject =
-        getOpenChangesByProject(db);
+        getOpenChangesByProject(db, ui);
     ui.message("done");
 
     ui.message("Updating groups for open changes ...");
@@ -140,7 +144,9 @@ public class Schema_108 extends SchemaVersion {
   }
 
   private SetMultimap<Project.NameKey, Change.Id> getOpenChangesByProject(
-      ReviewDb db) throws OrmException {
+      ReviewDb db, UpdateUI ui) throws OrmException {
+    SortedSet<NameKey> projects = repoManager.list();
+    SortedSet<NameKey> nonExistentProjects = Sets.newTreeSet();
     SetMultimap<Project.NameKey, Change.Id> openByProject =
         HashMultimap.create();
     for (Change c : db.changes().all()) {
@@ -149,10 +155,22 @@ public class Schema_108 extends SchemaVersion {
         continue;
       }
 
-      // The old "submitted" state is not supported anymore
-      // (thus status is null) but it was an opened state and needs
-      // to be migrated as such
-      openByProject.put(c.getProject(), c.getId());
+      NameKey projectKey = c.getProject();
+      if (!projects.contains(projectKey)) {
+        nonExistentProjects.add(projectKey);
+      } else {
+        // The old "submitted" state is not supported anymore
+        // (thus status is null) but it was an opened state and needs
+        // to be migrated as such
+        openByProject.put(projectKey, c.getId());
+      }
+    }
+
+    if (!nonExistentProjects.isEmpty()) {
+      ui.message("Detected open changes referring to the following non-existent projects:");
+      ui.message(Joiner.on(", ").join(nonExistentProjects));
+      ui.message("It is highly recommended to remove\n"
+          + "the obsolete open changes, comments and patch-sets from your DB.\n");
     }
     return openByProject;
   }