Rollback to Nexus 3.76#

wget https://repo1.maven.org/maven2/com/h2database/h2/2.2.224/h2-2.2.224.jar -O h2.jar

unzip nexus-backup/restore-from-backup/nexus-*.zip -d /tmp/nexus-restore

cat > rollback_db_to_3.76.sh << 'EOF'
#!/bin/bash
# Automatically rollback Nexus H2 database to flyway_schema_history version 2.10 (no confirmation required)

# Usage: ./rollback_db_to_3.76.sh <db_path> <h2_jar_path>
# Example: ./rollback_db_to_3.76.sh ./nexus ./h2.jar

set -e

# Check if required arguments are provided
if [ $# -ne 2 ]; then
    echo "Usage: $0 <db_path> <h2_jar_path>"
    echo "Example: $0 ./nexus ./h2.jar"
    echo ""
    echo "Arguments:"
    echo "  db_path      - Path to H2 database (without .mv.db extension)"
    echo "  h2_jar_path  - Path to H2 JAR file"
    exit 1
fi

DB_PATH="$1"
H2_JAR="$2"

# Validate H2 JAR exists
if [ ! -f "$H2_JAR" ]; then
    echo "Error: H2 JAR file not found: $H2_JAR"
    exit 1
fi

# Validate database file exists
if [ ! -f "${DB_PATH}.mv.db" ]; then
    echo "Error: Database file not found: ${DB_PATH}.mv.db"
    exit 1
fi

echo "================================"
echo "Starting rollback to version 2.10"
echo "================================"
echo "Database: ${DB_PATH}.mv.db"
echo "H2 JAR: $H2_JAR"
echo ""

# Create backup of the database file
cp "${DB_PATH}.mv.db" "${DB_PATH}.mv.db.backup-$(date +%Y%m%d%H%M%S)"
echo "Backup created: ${DB_PATH}.mv.db.backup-*"

# 1. Check current version
echo "Current version:"
java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'SELECT "version", "description" FROM "flyway_schema_history" WHERE "version" IS NOT NULL ORDER BY "installed_rank" DESC LIMIT 1;'

# 2. Count records to be deleted
echo ""
echo "Migration records to be deleted (installed_rank > 49):"
RECORDS_COUNT=$(java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'SELECT COUNT(*) FROM "flyway_schema_history" WHERE "installed_rank" > 49;' | grep -E "^[0-9]+$" | head -1)
echo "Total records to delete: $RECORDS_COUNT"

# 3. Display records to be deleted
echo ""
echo "Detailed records:"
java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'SELECT "installed_rank", "version", "description" FROM "flyway_schema_history" WHERE "installed_rank" > 49 ORDER BY "installed_rank" ASC;'

# 4. Execute deletion
echo ""
echo "Deleting records..."
java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'DELETE FROM "flyway_schema_history" WHERE "installed_rank" > 49;'

# 5. Verify results
echo ""
echo "================================"
echo "Rollback completed!"
echo "================================"
echo ""
echo "Current version:"
java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'SELECT "version", "description", "installed_on" FROM "flyway_schema_history" WHERE "version" IS NOT NULL ORDER BY "installed_rank" DESC LIMIT 1;'

echo ""
echo "Remaining migration records:"
java -cp "$H2_JAR" org.h2.tools.Shell -url "jdbc:h2:$DB_PATH" -user "" -password "" -sql 'SELECT COUNT(*) as total_records FROM "flyway_schema_history";'

echo ""
echo "================================"
echo "Important Notes:"
echo "1. ✅ flyway_schema_history table has been rolled back to 2.10"
echo "2. ⚠️  Please ensure to restore the rolled-back database file to your Nexus 3.76 instance."
echo "================================"
EOF

chmod +x rollback_db_to_3.76.sh
./rollback_db_to_3.76.sh /tmp/nexus-restore/nexus ./h2.jar
mkdir -p /tmp/nexus-restore/rolledback
cp /tmp/nexus-restore/nexus.mv.db /tmp/nexus-restore/rolledback/nexus.mv.db