Question

我正在尝试使用feathersjs-sequelize和mysql数据库重现Java / Hibernate / TABLE Sequence功能https://dzone.com/articles/hibernate-identity-sequence。

所以，我在mysql中创建了以下函数

FUNCTION `generate_pessoa_seq`() RETURNS bigint(16)
BEGIN
DECLARE R_ID BIGINT(16);
UPDATE pessoa_seq SET next_value = next_value + 1;
SELECT next_value INTO R_ID FROM pessoa_seq;
RETURN R_ID;

之后我在mysql cli中测试了：

mysql> select generate_pessoa_seq();
+-----------------------+
| generate_pessoa_seq() |
+-----------------------+
|                    11 |
+-----------------------+
1 row in set (0,00 sec)

确定。现在我可以使用11作为我的表的ID值“pessoa”。

所以我试图按照下面的想法（pessoa hook）

const pessoaBeforeCreateHook = options => { // always wrap in a function so you can pass options and for consistency.
  return hook => {
    console.log('Pessoa hook ' + hook);

    sequelize = hook.app.get('sequelize');
    var newId = -1; //forcing an error
    sequelize.query('select generate_pessoa_seq();',{ type: sequelize.QueryTypes.SELECT}).then(function(response){

       //getNewId();
       newId = response;

    }).error(function(err){
      console.log(err);
      newId=-1;
    });
    hook.data.IdiPessoa=newId;
    return Promise.resolve(hook); // A good convention is to always return a promise.
  };
};

exports.before = {
  all: [],
  find: [],
  get: [],
  create: [pessoaBeforeCreateHook()],
  update: [],
  patch: [],
  remove: []
};

感谢您的帮助。

Answer 1

达夫尔说：

Sequelize查询返回一个promise并以异步方式运行，因此在解析后要运行的任何逻辑都需要在.then处理程序中。您还必须从钩子函数返回该承诺，以便它等待它完成：

所以，最终的代码在这里：

pessoaService.hooks({
  before: {
    create(hook) {
    const sequelize = app.get('sequelize');
    var newId = -1; //forcing an error 
    return sequelize.query('select generate_pessoa_seq() as nextId;',{
      nest: true,
      raw: true }).then(function(response){
        //getNewId();
        var stringId = response[0];
        newId =  parseInt(stringId.nextId, 10);
        hook.data.IdiPessoa=newId;
        return hook;
      }).error(function(err){
        console.log(err);
        return hook; 
      });
    }
  }
});

如何在创建钩子CALL一个mysql函数之前使用-shquelize-sequelize

1 个答案: