mybatis-plus 租户处理器

配置

租户解析器处理程序

import com.baomidou.mybatisplus.extension.plugins.tenant.TenantSqlParser;
import net.sf.jsqlparser.expression.BinaryExpression;
import net.sf.jsqlparser.expression.Expression;
import net.sf.jsqlparser.expression.Parenthesis;
import net.sf.jsqlparser.expression.operators.conditional.AndExpression;
import net.sf.jsqlparser.expression.operators.conditional.OrExpression;
import net.sf.jsqlparser.expression.operators.relational.*;
import net.sf.jsqlparser.schema.Column;
import net.sf.jsqlparser.schema.Table;
import net.sf.jsqlparser.statement.select.*;

import java.util.List;

/**   
* Mp租户解析器处理程序
* @author xxm  
* @date 2020/4/15 11:40
*/
public class MpTenantParserHandler extends TenantSqlParser {

	/**
	 * 目前仅支持：in, between, >, <, =, !=等比较操作，处理多租户的字段加上表别名
	 */
	protected Expression processTableAlias(Expression expression, Table table) {
		String tableAliasName;
		if (table.getAlias() == null) {
			tableAliasName = table.getName();
		} else {
			tableAliasName = table.getAlias().getName();
		}
		if (expression instanceof InExpression) {
			InExpression in = (InExpression) expression;
			if (in.getLeftExpression() instanceof Column) {
				setTableAliasNameForColumn((Column) in.getLeftExpression(), tableAliasName);
			}
		} else if (expression instanceof BinaryExpression) {
			BinaryExpression compare = (BinaryExpression) expression;
			if (compare.getLeftExpression() instanceof Column) {
				setTableAliasNameForColumn((Column) compare.getLeftExpression(), tableAliasName);
			} else if (compare.getRightExpression() instanceof Column) {
				setTableAliasNameForColumn((Column) compare.getRightExpression(), tableAliasName);
			}
		} else if (expression instanceof Between) {
			Between between = (Between) expression;
			if (between.getLeftExpression() instanceof Column) {
				setTableAliasNameForColumn((Column) between.getLeftExpression(), tableAliasName);
			}
		}
		return expression;
	}

	private void setTableAliasNameForColumn(Column column, String tableAliasName) {
		column.setColumnName(tableAliasName + "." + column.getColumnName());
	}

	/**
	 * 默认是按 tenant_id=1 按等于条件追加
	 *
	 * @param currentExpression 现有的条件：比如你原来的sql查询条件
	 * @param table
	 * @return
	 */
	@Override
	protected Expression builderExpression(Expression currentExpression, Table table) {
		final Expression tenantExpression = this.getTenantHandler().getTenantId(true);
		Expression appendExpression;
		if (!(tenantExpression instanceof SupportsOldOracleJoinSyntax)) {
			appendExpression = new EqualsTo();
			((EqualsTo) appendExpression).setLeftExpression(this.getAliasColumn(table));
			((EqualsTo) appendExpression).setRightExpression(tenantExpression);
		} else {
			appendExpression = processTableAlias(tenantExpression, table);
		}
		if (currentExpression == null) {
			return appendExpression;
		}
		if (currentExpression instanceof BinaryExpression) {
			BinaryExpression binaryExpression = (BinaryExpression) currentExpression;
			if (binaryExpression.getLeftExpression() instanceof FromItem) {
				processFromItem((FromItem) binaryExpression.getLeftExpression());
			}
			if (binaryExpression.getRightExpression() instanceof FromItem) {
				processFromItem((FromItem) binaryExpression.getRightExpression());
			}
		} else if (currentExpression instanceof InExpression) {
			InExpression inExp = (InExpression) currentExpression;
			ItemsList rightItems = inExp.getRightItemsList();
			if (rightItems instanceof SubSelect) {
				processSelectBody(((SubSelect) rightItems).getSelectBody());
			}
		}
		if (currentExpression instanceof OrExpression) {
			return new AndExpression(new Parenthesis(currentExpression), appendExpression);
		} else {
			return new AndExpression(currentExpression, appendExpression);
		}
	}

	@Override
	protected void processPlainSelect(PlainSelect plainSelect, boolean addColumn) {
		FromItem fromItem = plainSelect.getFromItem();
		if (fromItem instanceof Table) {
			Table fromTable = (Table) fromItem;
			if (!this.getTenantHandler().doTableFilter(fromTable.getName())) {
				plainSelect.setWhere(builderExpression(plainSelect.getWhere(), fromTable));
				if (addColumn) {
					plainSelect.getSelectItems().add(new SelectExpressionItem(new Column(this.getTenantHandler().getTenantIdColumn())));
				}
			}
		} else {
			processFromItem(fromItem);
		}
		List<Join> joins = plainSelect.getJoins();
		if (joins != null && joins.size() > 0) {
			joins.forEach(j -> {
				processJoin(j);
				processFromItem(j.getRightItem());
			});
		}
	}
}

代码100分

租户处理器

代码100分/**
 * sql租户解析器
 * @author xxm
 * @date 2020/4/14 15:28
 */
@Component
@AllArgsConstructor
public class MpTenantHandler implements TenantHandler {

	private final HeaderHolder headerHolder;

	/**
	 * 租户值
	 */
	@Override
	public Expression getTenantId(boolean where) {
		Long tid = headerHolder.findTid();
		return new LongValue(tid);
	}

	/**
	 * 租户字段名称
	 */
	@Override
	public String getTenantIdColumn() {
		return "tid";
	}

	@Override
	public boolean doTableFilter(String tableName) {
		//TODO 如果是超级租户 不进行过滤
		return Objects.equals(headerHolder.getTid(), 1L);
	}
}

MP配置

/**   
* mp配置
* @author xxm  
* @date 2020/4/8 14:05
*/
@Configuration
public class MybatisPlusConfig {

    /**
     * 多租户属于 SQL 解析部分，依赖 MP 分页插件
     */
    @Bean
    public PaginationInterceptor paginationInterceptor(MpTenantHandler mpTenantHandler) {
        PaginationInterceptor paginationInterceptor = new PaginationInterceptor();

        List<ISqlParser> sqlParserList = new ArrayList<>();
        TenantSqlParser tenantSqlParser = new MpTenantParserHandler();
        // 解析处理拦截器
        tenantSqlParser.setTenantHandler(mpTenantHandler);

        sqlParserList.add(tenantSqlParser);
        paginationInterceptor.setSqlParserList(sqlParserList);
        return paginationInterceptor;
    }
}

租户字段处理

代码100分public class BaseEntity {
    /** 租户id */
    @TableField(insertStrategy = FieldStrategy.NEVER,
            updateStrategy = FieldStrategy.NEVER)
    private Long tid;
}

插入和更新时租户字段由租户处理器接管，mp自带的增删改查不再有租户字段

查询

插入

/**
     * insert 语句处理
     */
    @Override
    public void processInsert(Insert insert) {
        if (tenantHandler.doTableFilter(insert.getTable().getName())) {
            // 过滤退出执行
            return;
        }
        insert.getColumns().add(new Column(tenantHandler.getTenantIdColumn()));
        if (insert.getSelect() != null) {
            processPlainSelect((PlainSelect) insert.getSelect().getSelectBody(), true);
        } else if (insert.getItemsList() != null) {
            // fixed github pull/295
            ItemsList itemsList = insert.getItemsList();
            if (itemsList instanceof MultiExpressionList) {
                ((MultiExpressionList) itemsList).getExprList().forEach(el -> el.getExpressions().add(tenantHandler.getTenantId(false)));
            } else {
                ((ExpressionList) insert.getItemsList()).getExpressions().add(tenantHandler.getTenantId(false));
            }
        } else {
            throw ExceptionUtils.mpe("Failed to process multiple-table update, please exclude the tableName or statementId");
        }
    }

更新

/**
 * update 语句处理
 */
@Override
public void processUpdate(Update update) {
    final Table table = update.getTable();
    if (tenantHandler.doTableFilter(table.getName())) {
        // 过滤退出执行
        return;
    }
    update.setWhere(this.andExpression(table, update.getWhere()));
}

删除

/**
 * delete 语句处理
 */
@Override
public void processDelete(Delete delete) {
    if (tenantHandler.doTableFilter(delete.getTable().getName())) {
        // 过滤退出执行
        return;
    }
    delete.setWhere(this.andExpression(delete.getTable(), delete.getWhere()));
}