通过集成了flyway/liquibase等工具的gh-ost进行在线迁移

Question

我一直在研究如何使用gh-ost，它似乎还没有集成到像flyway/liquibase这样的工具中。gh-ost必须像这样运行：

./gh-ost --host=XXX--user=XXXX--password=XXXX--database=XXX--table=XXX --alter="ADD COLUMN XXX INT NOT NULL DEFAULT '0'"

表名和"alter“sql命令似乎是gh-ost命令参数的一部分。

有没有什么方法可以使用像flyway/liquibase这样的工具所提供的最大好处(在线模式迁移)？

Answer 1

它看起来并不是微不足道的。使用Flyway，您可以使用Custom Migration resolvers & executors在gh-ost命令中包装特殊文件。为了进行概念验证，您可以使用java类迁移来调用操作系统来运行Gh-ost命令。

Answer 2

private Flyway flyway = new Flyway();

GhostMigrationResolver ghostMigrationResolver = new GhostMigrationResolver();
flyway.setResolvers(ghostMigrationResolver);

public class GhostMigrationResolver extends BaseMigrationResolver {

    private Set<String> ghostScriptFiles = new HashSet<>();

    public void addGhostScript(String ghostUpdateScript) {
        ghostScriptFiles.add(ghostUpdateScript);
    }

    @Override
    public Collection<ResolvedMigration> resolveMigrations() {
        Set<ResolvedMigration> resolvedMigrations = new HashSet<>();
        for (String ghostScriptFile : ghostScriptFiles) {
            GhostResolvedMigration ghostResolvedMigration = new GhostResolvedMigration();
            ghostResolvedMigration.setScript(ghostScriptFile);
            GhostExecutor executor = new GhostExecutor();
            executor.setGhostScriptFile(ghostScriptFile);
            ghostResolvedMigration.setExecutor(executor);
            ghostResolvedMigration.setDescription(ghostScriptFile);
            ghostResolvedMigration.setVersion(MigrationVersion.fromVersion(ghostScriptFile.substring(1, ghostScriptFile.indexOf("__"))));
            ghostResolvedMigration.setType(MigrationType.CUSTOM);
            resolvedMigrations.add(ghostResolvedMigration);
        }
        return resolvedMigrations;
    }
}

public class GhostExecutor implements MigrationExecutor {

    @Override
    public void execute(Connection connection) throws SQLException {
    //call ghost here
    }
}