javascript - 从 .catch(error) 返回未在 Node/Express 中返回

Question

我正在编写 REST API 并尝试正确处理任何错误。

当API调用成功时，成功对象将返回给调用函数，并将响应发送给客户端。但是如果发生错误，我想将错误返回给调用函数，以便我可以向客户端发送错误消息。

router.delete('/project', (req, res) => {
  return DeleteProject(userId, projectId)
    .then((response) => {
      //handle response
    });
});

DeleteProject: (userId, projectId) => {
  return deleteProject(userId, projectId)
    .then((response) => { 
      return response
    })
    .catch((error) => {
      console.log('Error in DeleteProject:', error) // This happens.
      return error; // this doesn't happen.
    })
},

function deleteProject(userId, projectId) {
  return Project.deleteOne( ... delete the project... )
    .then((response) => {
      return response
    })
    .catch((error) => {
      return error
    })
}

上面中间函数DeleteProject()中的.catch(error)在发生错误时被触发(即控制台日志发生)，但返回并不会返回到路由器。

如何返回错误以供路由器处理？

Answer 1

您可以简单地从其他两个函数中删除 catch 方法，并将 catch 函数放入路由器本身中。然后错误本身将传播到您的路由器功能

router.delete('/project', (req, res) => {
  return DeleteProject(userId, projectId)
    .then((response) => {
      //handle response
    }).catch(() => {
       // Add catch function here. Any error in "DeleteProject" and "deleteProject" will propagate to here
    })
});

DeleteProject: (userId, projectId) => {
  return deleteProject(userId, projectId)
    .then((response) => { 
      return response
    });
    // Remove catch function
},

function deleteProject(userId, projectId) {
  return Project.deleteOne( ... delete the project... )
    .then((response) => {
      return response
    });
    // Remove catch function
}