Merge pull request #1081 from tdonohue/DS-2701-service-api-flyway-cle…

…anup

DS-2701: Bug fix, cleanup and pgcrypto checking

dspace-api/src/main/java/org/dspace/storage/rdbms/PostgreSQLCryptoChecker.java

@@ -0,0 +1,189 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.storage.rdbms;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.Statement;
+import org.apache.log4j.Logger;
+import org.flywaydb.core.api.FlywayException;
+import org.flywaydb.core.api.MigrationInfo;
+import org.flywaydb.core.api.callback.FlywayCallback;
+
+/**
+ * This is a FlywayCallback class which automatically verifies that "pgcrypto"
+ * is at the proper version before running any database migrations.
+ * <P>
+ * When running PostgreSQL, pgcrypto is REQUIRED by DSpace as it allows UUIDs
+ * to be generated.
+ * <P>
+ * During a database "clean", this also de-registers "pgcrypto" proir to the
+ * full database clean.
+ *
+ * @author Tim Donohue
+ */
+public class PostgreSQLCryptoChecker implements FlywayCallback
+{
+    private Logger log = Logger.getLogger(PostgreSQLCryptoChecker.class);
+
+    /**
+     * Check for pgcrypto (if needed). Throws an exception if pgcrypto is
+     * not installed or needs an upgrade.
+     * @param connection database connection
+     */
+    public void checkPgCrypto(Connection connection)
+    {
+        String dbType;
+        try
+        {
+            dbType = DatabaseUtils.getDbType(connection);
+        }
+        catch(SQLException se)
+        {
+            throw new FlywayException("Unable to determine database type.", se);
+        }
+
+        // ONLY Check if this is a PostgreSQL database
+        if(dbType!=null && dbType.equals(DatabaseUtils.DBMS_POSTGRES))
+        {
+            // If this is a PostgreSQL database, then a supported version
+            // of the 'pgcrypto' extension MUST be installed to continue.
+
+            // Check if pgcrypto is both installed & a supported version
+            if(!PostgresUtils.isPgcryptoUpToDate())
+            {
+                throw new FlywayException("This PostgreSQL Database is INCOMPATIBLE with DSpace. The upgrade will NOT proceed. " +
+                        "A supported version (>=" + PostgresUtils.PGCRYPTO_VERSION + ") of the '" + PostgresUtils.PGCRYPTO + "' extension must be installed! " +
+                        "Please run 'dspace database info' for additional info/tips.");
+            }
+        }
+    }
+
+    /**
+     * Remove pgcrypto (if necessary).
+     * <P>
+     * The pgcrypto extension MUST be removed before a clean or else errors occur.
+     * This method checks if it needs to be removed and, if so, removes it.
+     * @param connection database connection
+     */
+    public void removePgCrypto(Connection connection)
+    {
+        try
+        {
+            String dbType = DatabaseUtils.getDbType(connection);
+
+            // ONLY remove if this is a PostgreSQL database
+            if(dbType!=null && dbType.equals(DatabaseUtils.DBMS_POSTGRES))
+            {
+                // Get current schema
+                String schema = DatabaseUtils.getSchemaName(connection);
+
+                // Check if pgcrypto is in this schema
+                // If so, it MUST be removed before a 'clean'
+                if(PostgresUtils.isPgcryptoInSchema(schema))
+                {
+                    // remove the extension
+                    try(Statement statement = connection.createStatement())
+                    {
+                        // WARNING: ONLY superusers can remove pgcrypto. However, at this point,
+                        // we have already verified user acct permissions via PostgresUtils.checkCleanPermissions()
+                        // (which is called prior to a 'clean' being triggered).
+                        statement.execute("DROP EXTENSION " + PostgresUtils.PGCRYPTO + " CASCADE");
+                    }
+                }
+            }
+        }
+        catch(SQLException e)
+        {
+            throw new FlywayException("Failed to check for and/or remove '" + PostgresUtils.PGCRYPTO + "' extension", e);
+        }
+    }
+
+    @Override
+    public void beforeClean(Connection connection) {
+        // If pgcrypto is installed, remove it
+        removePgCrypto(connection);
+    }
+
+    @Override
+    public void afterClean(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeMigrate(Connection connection) {
+        // Before migrating database, check for pgcrypto
+        checkPgCrypto(connection);
+    }
+
+    @Override
+    public void afterMigrate(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeEachMigrate(Connection connection, MigrationInfo migrationInfo) {
+
+    }
+
+    @Override
+    public void afterEachMigrate(Connection connection, MigrationInfo migrationInfo) {
+
+    }
+
+    @Override
+    public void beforeValidate(Connection connection) {
+
+    }
+
+    @Override
+    public void afterValidate(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeInit(Connection connection) {
+
+    }
+
+    @Override
+    public void afterInit(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeBaseline(Connection connection) {
+        // Before initializing database, check for pgcrypto
+        checkPgCrypto(connection);
+    }
+
+    @Override
+    public void afterBaseline(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeRepair(Connection connection) {
+
+    }
+
+    @Override
+    public void afterRepair(Connection connection) {
+
+    }
+
+    @Override
+    public void beforeInfo(Connection connection) {
+
+    }
+
+    @Override
+    public void afterInfo(Connection connection) {
+
+    }
+}