node.js - 使用 Entity Schema 的 TypeORM 一对多关系

Question

我有两个实体项目和订单。我想在项目中有一对多订单，在订单中有多对一项目。

多对一端工作正常。

当我尝试在项目实体中添加一对多并尝试获取所有内容时，出现以下错误:

"Cannot read property 'joinColumns' of undefined"

项目实体

const { EntitySchema } = require('typeorm');
const { BaseRelations, BaseColumns } = require('../BaseEntity');

module.exports = new EntitySchema({
  name: 'Project',    
  columns: {
    ...BaseColumns,
    name: {
      type: 'varchar',
    }
  },
  relations: {
    ...BaseRelations,
    orders: {
      type: 'one-to-many',
      target: 'Order',
      cascade: true,
    },
  },
});

订单实体

const { EntitySchema } = require('typeorm');

module.exports = new EntitySchema({
  name: 'Order',
  columns: {
    id: {
      primary: true,
      type: 'int',
      generated: true,
    },
    name: {
      type: 'varchar',
      name: 'name',
    },
  },
  relations: {
    project: {
      type: 'many-to-one',
      target: 'Project',
      joinColumn: {
        name: 'project_id',
      },
    }
  },
});

Answer 1

想通了。对于面临类似问题的任何人。您需要在两个实体模式中定义 inverseSide。 inverseSide 值应该是在关系另一端的实体中定义的关系名称。

因此，对于我上面的实体，我需要进行以下更改:

项目实体:

const { EntitySchema } = require('typeorm');
const { BaseRelations, BaseColumns } = require('../BaseEntity');

module.exports = new EntitySchema({
  name: 'Project',    
  columns: {
    ...BaseColumns,
    name: {
      type: 'varchar',
    }
  },
  relations: {
    ...BaseRelations,
    orders: {
      type: 'one-to-many',
      target: 'Order',
      cascade: true,
      inverseSide: 'project' // Note that this is relation name, not the entity name
    },
  },
});

订单实体:

const { EntitySchema } = require('typeorm');

module.exports = new EntitySchema({
  name: 'Order',
  columns: {
    id: {
      primary: true,
      type: 'int',
      generated: true,
    },
    name: {
      type: 'varchar',
      name: 'name',
    },
  },
  relations: {
    project: {
      type: 'many-to-one',
      target: 'Project',
      joinColumn: {
        name: 'project_id',
      },
      inverseSide: 'orders' // Note that this is the relation name in project entity, no the entity name Order
    }
  },
});