com.wizarius.orm.migrations.DBMigration Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of wizarius-orm Show documentation
Java orm for Postgres or Mysql with migration system and connection pool
The newest version!
package com.wizarius.orm.migrations;

import com.fasterxml.jackson.annotation.JsonIgnore;
import com.wizarius.orm.database.DBException;
import com.wizarius.orm.database.connection.DBConnection;
import com.wizarius.orm.database.connection.DBConnectionPool;
import lombok.extern.slf4j.Slf4j;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

/**
 * Created by Vladyslav Shyshkin on 24.11.2017.
 */
@SuppressWarnings("WeakerAccess")
@Slf4j
public abstract class DBMigration {
    /**
     * Migration level
     */
    private final int level;
    /**
     * Migration name
     */
    private final String name;
    /**
     * Connection pool
     */
    private DBConnectionPool pool;
    /**
     * Commands to execute
     */
    private final List commandsToExecute = new ArrayList<>();

    public DBMigration(int level, String name) {
        this.level = level;
        this.name = name;
    }

    /**
     * Execute migration
     *
     * @throws DBMigrationException on unable to execute
     */
    final void execute() throws DBMigrationException {
        if (isInTransaction()) {
            executeInTransactionBlock();
        } else {
            executeQueries();
        }
    }

    /**
     * Start transaction before up
     *
     * @throws DBMigrationException on unable to start
     */
    private void executeInTransactionBlock() throws DBMigrationException {
        log.info("Execute migration command in transaction block where commands count = {}", commandsToExecute.size());
        try (DBConnection connection = pool.getConnection()) {
            connection.startTransaction();
            for (String sql : commandsToExecute) {
                log.trace("Execute migration sql = " + sql);
                connection.executeQuery(sql);
            }
            connection.commitTransaction();
        } catch (DBException e) {
            // do not need to do rollback, it will happen in the close method
            throw new DBMigrationException("Unable to get connection. " + e.getMessage(), e);
        } catch (SQLException e) {
            // do not need to do rollback, it will happen in the close method
            throw new DBMigrationException("Unable to start or commit transaction. " + e.getMessage(), e);
        }
    }

    /**
     * Execute queries
     *
     * @throws DBMigrationException on unable to execute query
     */
    private void executeQueries() throws DBMigrationException {
        log.info("Execute migration command where commands count = {}", commandsToExecute.size());
        try (DBConnection connection = pool.getConnection()) {
            for (String sql : commandsToExecute) {
                log.trace("Execute migration sql = " + sql);
                connection.executeQuery(sql);
            }
        } catch (DBException e) {
            throw new DBMigrationException("Unable to get connection. " + e.getMessage(), e);
        } catch (SQLException e) {
            throw new DBMigrationException("Unable to execute query. " + e.getMessage(), e);
        }
    }

    /**
     * On setup migration
     */
    public abstract void up();

    /**
     * Execute sql
     *
     * @param sql sql string
     */
    protected final void executeSQL(String sql) {
        commandsToExecute.add(sql);
    }

    /**
     * Returns true if need execute migration in transaction block
     *
     * @return execute in transaction block
     */
    protected boolean isInTransaction() {
        return true;
    }

    /**
     * Execute sql
     * Example
     * InputStream in = getClass().getClassLoader().getResourceAsStream("migrations/initial.sql");
     *
     * @param stream input stream
     * @throws IOException on unable to read from file
     */
    protected final void executeSQL(InputStream stream) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
        StringBuilder sb = new StringBuilder();
        String line;
        while ((line = reader.readLine()) != null) {
            sb.append(line);
        }
        String[] commands = sb.toString().split(";");
        for (String command : commands) {
            executeSQL(command);
        }
    }

    /**
     * Get migration level
     *
     * @return migration level
     */
    public int getLevel() {
        return level;
    }

    /**
     * Get migration name
     *
     * @return migration name
     */
    public String getName() {
        return name;
    }

    /**
     * Setup connection pool
     *
     * @param pool pool to setup
     */
    public void setupConnectionPool(final DBConnectionPool pool) {
        this.pool = pool;
    }

    /**
     * Get connection pool to database
     *
     * @return connection pool
     */
    @JsonIgnore
    public DBConnectionPool getPool() {
        return pool;
    }

    @Override
    public String toString() {
        return "DBMigration{" +
                "level=" + level +
                ", name='" + name + '\'' +
                ", pool=" + pool +
                ", commandsToExecute=" + commandsToExecute +
                '}';
    }
}